Page 2 · 4400 Series LaserSource User’s Manual

Table of Contents
Introduction ............................................................................................... 4
Safety Terms and Symbols ....................................................................... 6
Quick Start ................................................................................................ 8
Installation ................................................................................................. 9Powering Up the Unit............................................................................ 9
Ventilation ............................................................................................. 9
Rack Mounting ...................................................................................... 9
Warm-up and Environmental Considerations .................................... 10
Front Panel Connections ........................................................................ 10
Modulation Input ................................................................................. 10
Trigger Input & Output ........................................................................ 10
Rear Panel Connections ......................................................................... 11
13W3 Laser Output Connector ........................................................... 11
Bus Bar Laser Output Connector ....................................................... 12
Auxiliary Connector ............................................................................ 13
Interlock Connector ............................................................................ 13
USB Connector ................................................................................... 13
RS232 Connector ............................................................................... 14
Front Panel Operation ............................................................................. 15
Main Display Screen ........................................................................... 16
Using Limits ........................................................................................ 17
Status Messages ................................................................................ 18
Settings and Menus ................................................................................ 18
Main Laser Menu ..................................................................................... 19
Pilot Laser Menu ..................................................................................... 24
Remote Mode Operation......................................................................... 26
Installing the USB Drivers ....................................................................... 26
Connecting to the LaserSource .............................................................. 26
Grounding Considerations ...................................................................... 27
Cable Wiring for Modulation and QCW .................................................. 28
Laser Control Modes ............................................................................... 29
Modulation .......................................................................................... 30
Using QCW Modes ................................................................................. 30
QCW Low Setpoint ............................................................................. 32
Trigger Input and Trigger Output ....................................................... 33
Trigger In and Trigger Out Delay ........................................................ 33
Risetime Control ................................................................................. 33
Using Limits............................................................................................. 34

4400 Series LaserSource User’s Manual · Page 3

Voltage Operating Region....................................................................... 34
Using the Cable R Setting ....................................................................... 35
Measure the Voltage at the Laser ....................................................... 35
Short the Connection at the End of the Cable ................................... 36
How the Calculation Is Used .............................................................. 36
Using Remote Voltage Sense ................................................................. 36
Using Remote Voltage Sense ............................................................. 37
Using the Auxiliary Interface.................................................................... 38
Auxiliary Sensors ................................................................................ 38
Digital Inputs ....................................................................................... 38
Digital Outputs .................................................................................... 39
Relay ................................................................................................... 39
Dig Out Modes.................................................................................... 40
Using the Interlocks ................................................................................ 41
The Laser Interlock/LED Interface ........................................................... 41
Closing the Circuit .............................................................................. 41
Working With Thermistors ....................................................................... 42
The Steinhart-Hart Equation ............................................................... 43
Analog Modulation .................................................................................. 44
Optimizing for Pulse Performance .......................................................... 45
Cables ................................................................................................. 45
Lowering BW or Risetime ................................................................... 46
Dead Shorts ........................................................................................ 46
Eliminating E-537 (Thermal Overload) Error ...................................... 46
Eliminating E-540 (Voltage Headroom) Error ..................................... 47
Eliminating E-505 (Voltage Limit) Error .............................................. 47
Eliminating E-541 (Excessive Current Detected) Error....................... 47
Noise ................................................................................................... 48
Voltage Limit / Headroom Disable ...................................................... 48
Using the Pilot Laser ............................................................................... 49
Using the Function Keys ......................................................................... 49
Running a script.................................................................................. 49
Loading a previously stored configuration ......................................... 50
User Calibration ...................................................................................... 51
Specifications .......................................................................................... 53
Error Messages ....................................................................................... 60
Maintenance and Service........................................................................ 63
Maintenance ....................................................................................... 63
Fuses .................................................................................................. 63
Service ................................................................................................ 63
EC Declaration of Conformity ................................................................. 65
UK Declaration of Conformity ................................................................. 66

Page 4 · 4400 Series LaserSource User’s Manual

Introduction
Thank you for choosing the LaserSource from Arroyo Instruments. Your
LaserSource is a combination of leading-edge technology combined with yearsof experience in the field of current control.
With a crystal clear VFD display, both RS232 and USB computer interfaces, andsmall footprint, the LaserSource will fit into almost any laser diode control
application.
A key feature of the LaserSource is its optical isolation of both modulation andphotodiode inputs. By isolating these inputs, it prevents unwanted ground loop
problems. No other laser diode driver in the industry has this feature.
Another important feature of the LaserSource is its ability to operate in quasiCW (QCW) mode. This mode permits operation of lasers to a higher current andpower, minimizing the thermal load by turning the laser on for only a brief periodof time, taking measurements, then turning off the laser. The LaserSource
supports both internal and external triggering of pulses, and also includes a
trigger out to synchronize the LaserSource with other instruments.
The LaserSource also operates in constant voltage control mode, allowing you
to use it in precision voltage applications, such as EML devices, or for doing V-I
measurement graphs.
The LaserSource includes another feature not found in other products: theability to program the photodiode bias level from the front panel or over thecomputer interface, to any voltage from 0 to -5V. No more tweaking a
potentiometer with a screwdriver and a DMM. Simply dial in the voltage you
need.
Unlike other laser diode drivers in its class, which use inexpensive 7-segment
displays, the LaserSource takes advantage of its large VFD display tosimultaneously show the set point, laser voltage, and photodiode read back.
The user interface of the LaserSource is engineered to make using the
instrument straightforward. With its text-based menus, there is never any
confusion over which setting is being changed, and parameters are displayed inclear English (no cryptic numbers or LEDs to decode).
The LaserSource offers all the features you would expect from a modern
precision laser diode driver, including:••

10ppm current stability over one hour
10A to 100A current ranges

4400 Series LaserSource User’s Manual · Page 5

•
•
•
•

Comprehensive laser protection circuitry, including hardware voltage
and current limits, and fast transient shutdown.
External analog modulation
Power mode control, both in photodiode current (AMC) or computed
photodiode power (APC) modes.
Simultaneous reading of current set point, voltage measurement, andphotodiode current or power measurement.

What’s in the Box
Along with the LaserSource itself, a CD with electronic copies of this manual,
the Computer Interfacing Manual, and USB drivers are included. For USA
customers, a power cord is included. For non-USA customers, an IEC-60320C13 rated AC power cord must be provided.
Accessories
Arroyo Instruments also sells several accessories designed to work with theLaserSource. These include:
•

•
•
•
•

LaserSource Cables:o 1230: 20A, 2m, 13W3F connector on device end
o 1231: 20A, 2m, pigtailed (bare) wires on device end
o 1232: 40A, 2m, 13W3F connector on device end
o 1233: 40A, 2m, pigtailed (bare) wires on device end
4400/5400 Series 2U Rack Mount Kit (p/n 1403-RM)
For installing your 4400/5400 Series TECSource into a standard 19”
rack.
10kΩ Thermistor (p/n 1600-10K) for use with the auxiliary temperature
sensor inputs.
RS-232 NULL Cable, 3m (p/n 1200-NULL)
USB Cable, 3m (p/n 1201)

Page 6 · 4400 Series LaserSource User’s Manual

Safety Terms and Symbols
The following safety-related terms are used in this manual:•••Warnings (noted by the WARNING heading) explain dangers that
could result in physical injury or death.
Cautions (noted by the CAUTION heading) explain conditions that
could result in damage to the instrument, other equipment, or yourdevice.
Notes (noted by the NOTES heading) are not safety-related and areintended simply to point out important information.

If, at any time, any of the following conditions exist, or are suspected of existing,discontinue use of the unit until it can be inspected by qualified service
personnel:•••

Visible damage to the unit, including damage or stress caused during
product shipment.
Storage of the unit outside the standard storage temperature or
humidity rating, or prolonged storage under harsh conditions.
Failure to operate properly.

If needed, contact your distributor or Arroyo Instruments for service or repair toensure the safety of the product is maintained.
Symbols
Power OffPower On

Caution, refer to manual

Earth Ground

Caution, risk of electric shock4400 Series LaserSource User’s Manual · Page 7

General Warnings

WARNING
Potentially lethal voltages exist within this instrument.
This instrument is intended for use by qualified
personnel who understand the shock and laser hazards
and are familiar with safety procedures required to avoid
injury. Read this manual completely before attempting
to use this product.

WARNINGTo avoid electrical shock, ensure a 3-prong power cord
is used, and is plugged into an earth-grounded
receptacle. Failure to do so can result in severe injury or
death.

CAUTION

There are no user-serviceable parts inside. All service
and repair work shall be done by Arroyo Instruments or
personnel authorized by Arroyo Instruments.
Modifications done by non-authorized personnel willvoid the warranty. Please see the Service section laterin this manual for instructions on how to obtain service
for this instrument.

Page 8 · 4400 Series LaserSource User’s Manual

Quick Start
The LaserSource was designed with ease of use in mind. This section will show
how you can quickly get the unit up and running.
The unit uses a universal AC input, just ensure you are within the 100V to 250V
AC operating range. Plug the AC cord into the unit and into the wall outlet. Turnon the power switch located on the front panel, and the unit will power up,
displaying the model information, serial number, and firmware version number.
The most important setting of the controller is the current limit. A proper current
limit will ensure you do not over-drive the laser. The voltage limit is not as critical,
but a well-set voltage limit is also recommended.
Press the Menu button to enter the menu, and using the knob, turn to the right
until the Io Limit setting is displayed. This is perhaps the most critical setting
you can adjust on the instrument, as it will protect your laser against over-current
conditions. Press the knob to edit the setting and adjust the limit as appropriate
to your laser diode. Set a bit above the target operating current, as you do notwant to be driving into the limit. Press the knob again to save the value. Make
the same adjustments to the voltage limit (Vf Limit), setting between 0.5V and
1V above the typical operating voltage of your device (the extra voltage will take
into account any voltage losses in the cables and connectors). Once you havemade all your adjustments, press the Menu button to exit the menu.
Next, connect the cable between your LaserMount or other fixture and the
Output connector of the LaserSource. We recommend using our cables as they
have been designed to work well with the LaserSource. If using your own
cables, ensure they have been properly wired according to the pin-out of theLaserSource and your fixture.
When starting a system for the first time, it is recommended that you start withthe set point at zero and ramp up the set point to your target operating current.
The “gentle” turn-on is a good way to verify everything is hooked up correctly.
For subsequent turn-ons, you can leave the set point at your target and simply
turn the output on.
After a 3-second delay (defeatable, see On Delay setting), the output will turn on
and you will see the actual voltage of the laser displayed.
Detailed information on the operation of the unit can be found in the remainderof this manual.

4400 Series LaserSource User’s Manual · Page 9

Installation
Installation of the 4400 LaserSource is very straightforward, as the quick start
section above illustrated. This section will provide additional details andconsiderations for installing your LaserSource.
After unpacking the unit, make sure all packing materials have been removed
and nothing obscures the ventilation ports on the back and bottom of the unit.
The LaserSource has a universal input power supply, accepting 90 to 240 VAC,
and 50 or 60 Hz. This covers all conventional power worldwide but ensure yourAC power meets these requirements.

CAUTION
Do not exceed 250VAC on the line input.
Excessive line voltage can damage the controller.
Powering Up the Unit
Connect the AC power cord to the unit. Turn the power switch, located on thefront of the unit, into the on (|) position. The unit will display the current firmware
revision, go through a quick power-up self-test, and return to the last known
operating state.
Ventilation
The LaserSource has vent holes on the side and front of the unit. You must not
block these vent holes or overheating may occur causing damage to the unit.

CAUTION
Do not operate the unit above +40°C ambient, andensure the instrument is properly ventilated, or the unit
may overheat and possible damage to the unit may
occur.
Rack Mounting
The rack mounting kit (p/n 1403-RM) for standard 19” racks are available for theLaserSource. Because the unit draws air from the side, and therefore inside therack housing, be sure that the internal rack ambient temperature (which will

Page 10 · 4400 Series LaserSource User’s Manual

typically be several degrees higher than room ambient) does not exceed theunit’s operating temperature.
Warm-up and Environmental Considerations
In order to achieve the highest level of accuracy, the LaserSource should bepowered on for at least one hour prior to taking measurements. In addition,
ensure that the unit is not operating outside the ambient temperature range orhumidity conditions.

Front Panel Connections
The front panel has connections for modulation and QCW triggers.
Modulation Input
The modulation input BNC accepts a 0V to 10V input signal for analog set point
control of the driver. The modulation input is optically isolated from the rest of
the control circuits in the LaserSource and electrically isolated from ground, so
you should not need to be concerned about ground interference from any
modulation source.
BNC
Description
Center Pin
Signal+Shell
Signal–Modulation Connector (BNC)
Trigger Input & Output
The trigger input and output BNCs are used in QCW modes. For more
information on their use, see the Using QCW Modes section.
BNC
Description
Center Pin
Signal+Shell
GroundTrigger In and Trigger Out Connectors (BNCs)

4400 Series LaserSource User’s Manual · Page 11

Rear Panel Connections
In addition to the front panel connections described, the rear panel has
connections for AC power, Output connector or bus bars, Auxiliary connector,
Interlock connector, USB connector, and RS232 connector.

LaserSource Rear Panel, 40 Amp Rated Units and Below

LaserSource Rear Panel, Units Rated Above 40 Amps
13W3 Laser Output Connector
For controllers with a current rating of 40 Amps and lower, the Output connector
is a female 13W3, and has the following pin-out:
Pin
A1
A3
1
2
3
4
5

Description
Pin
Description
Laser CathodeA2
Earth Ground
Laser Anode
Interlock/LED+
6
Laser Cathode Remote Sense
Interlock/LED–
7
Photodiode Anode
Pilot Anode
8
Photodiode Cathode
Pilot Cathode9
Temperature Sensor
Laser Anode Remote Sense
10
Temperature Sensor
Output Connector (13W3 Female)Page 12 · 4400 Series LaserSource User’s Manual

Bus Bar Laser Output Connector
For controllers with a current rating of over 40 Amps, the Output connector isbus bar with M6 threaded holes.

The remaining signals are housed in a DB9 female signal connector directly
above the bus bar terminals:
Pin
1
2
3
4
5

Description
Pin
Description
Interlock/LED+
6
Photodiode CathodeInterlock/LED–
7
Photodiode AnodeEarth Ground
8
Pilot CathodeLaser Cathode Remote Sense
9
Pilot Anode
Laser Anode Remote Sense
Signal Connector (DB9 Female)

Using the Interlock/LED
The Interlock/LED pins can be used to drive an LED to indicate when the laser ison. The signal is driven from a +5V buffer with a 200Ω resistor in series with theoutput, limiting the current to 20mA. This is suitable for the direct connection ofmost green and red LEDs. Add additional series resistance for lower current
devices, such as blue LEDs.

Laser On LED Circuit Diagram
See Using the Interlocks section for additional information.

4400 Series LaserSource User’s Manual · Page 13

Using Remote Voltage Sense
The Remote Sense pins are used to remotely measure the laser voltage. See
Using Remote Voltage Sense section for more information.
Auxiliary Connector
The Auxiliary connector is a female DB-25, and has the following pin-out:
Pin
1
2
3
4
5
6
7
8
9
10
11
12
13

Description
Digital Input 1
Digital Input 2
Digital Output 1
Digital Output 2+5V (100mA MAX)
Relay N/C Contact
Relay N/O Contact
Reserved, no connection
Reserved, no connection

Auxiliary Sensor 1
Auxiliary Sensor 2
Reserved, no connection
Reserved, no connection

Pin
14
15
16
17
18
19
20
21
22
23
24
25

Description
Digital I/O Ground
Digital I/O Ground
Digital I/O Ground
Digital I/O Ground
Digital I/O Ground
Relay Common
Reserved, no connection
Reserved, no connection

Sensor Ground
Sensor GroundReserved, no connection
Reserved, no connection

Auxiliary Connector (DB-25 Female)
See Using the Auxiliary Interface section for more information on using theauxiliary interface.
Interlock Connector
The Interlock connector is a 2-pin Phoenix socket with the following pin-out:
Pin
Description
1
Interlock2
Interlock Ground
Interlock Connector (2-Pin Phoenix)
The mating plug is a Phoenix part number 1803578, and one is included with the
instrument. See Using the Interlocks section for additional information.
USB Connector
The USB connector is a standard Type B female connector. For more
information on using the USB interface, see the Computer Interfacing Manual
which is included on the CD that accompanied this product.

Page 14 · 4400 Series LaserSource User’s Manual

RS232 Connector
The RS232 connection is male DB-9 connector wired in a NULL modem
configuration.
Pin
Description
2
Receive
3
Transmit
5
Ground
1,4,6
Commoned together
7,8Commoned together
9
No connection
Shell
Earth ground
RS232 Connector (DB-9 Male)For more information on using the RS232 interface, see the Computer Interfacing
Manual which is included on the CD that accompanied this product.

4400 Series LaserSource User’s Manual · Page 15

Front Panel Operation
Operation of the LaserSource is very straightforward. The sections below will
help familiarize you with the front panel, the display, and the menu structure.

The front panel is designed for simplicity in operation. There are seven buttons
on the front panel: Output, Menu, Display, Func A, Func B, Pilot Laser, andthe adjustment knob button.
The Output button is used to turn the high-power laser output on and off.
Whenever the output is on, the blue Output On LED will be lit.
The Pilot Laser button is used to turn the Pilot Laser output on and off.
Whenever the output is on, the blue Pilot Laser Output On LED will be lit.
The Menu button is used to enter the LaserSource menu. When in remotemode, it acts as a Local button, returning the instrument to local mode. There
are two menus in the system: the Main Menu, which can be accessed bypressing the Menu button on any screen except the pilot laser, and the Pilot
Menu, which can only be accessed when on the pilot laser screen.
The Display button is used to cycle through the display modes of the controller.
Because the controller monitors more information than can be displayed atonce, the Display button allows you to cycle between the laser information,
auxiliary temperature measurements, digital I/O status, and pilot laser control.
The Func A and Func B buttons are used to execute user-defined macros,recall saved settings, or other actions as defined in the Function Keys Menu.
The large adjustment knob located on the right-hand side of the unit is used tochange the set point or parameters in the menu. It also acts as a push button,
primarily as an enter button, when making changes in the menu.

Page 16 · 4400 Series LaserSource User’s Manual

There are eleven LEDs:
Function
Main
Output On
Pilot
Output On
Error

Color

When lit, indicates:Blue

LaserSource is driving the main laser output

Blue

LaserSource is driving the pilot laser output

Red

Error has occurred

RemoteYellow

Unit is being controlled via a computer

Low

Green

Main laser output is in low current range

High

Green

Main laser output is in high current range

High BW

Green

Main laser output is in high bandwidth mode

QCW

Green

Main laser output is in QCW mode

Io Limit

Green

Main laser output is limiting current

InterlockYellow

System interlock is open

Link

Green

Controller is linked to another instrument

Whenever an error is generated, the red Error LED will light, and the error will be
displayed on the VFD display. There may be one or more errors, but only the
first error will be displayed. To display the next error, press Menu button. To
clear all errors, press the knob. A list of error codes can be found in the Error
Messages section.
When the unit is in remote mode, the yellow Remote LED will be lit. Moreinformation about how the instrument behaves in remote mode can be found in
the Remote Mode Operation section.
Main Display Screen
The top of the main display will be the set point or actual read of the control
mode value (for example, current when in constant current mode). The bottom
half of the display can display additional measurements depending on the modeof operation.
Example displays are shown below:

Io SET 5.000
Io= 5.000A
Im= 6657µA Vf=1.783v

4400 Series LaserSource User’s Manual · Page 17

Main Display: Constant current mode

Im SET 5000
Im= 5000µA
Io=18.239A Vf=1.783v
Main Display: constant photodiode power mode

Io SET 5.000
Ax1=28.65
Ax2=23.88

Ax3=28.65

Main Display: auxiliary temperature sensors

Io SET 5.000
Din 1/2/I:On /Off/Off
Dout 1/2/R:Off/Off/Off
Main Display: digital I/O state.PilotLaser.

IoSET= 25mA
Io=
25mA Vf= 1.78v
Main Display: pilot laser
The set point will depend on the control mode you have selected.
Using Limits
The LaserSource supports five different types of limits: current, voltage,
photodiode current, photodiode power, and temperature. Current and voltage
limits are implemented in hardware for high speed response. The other limits aremonitored in software with up to 100ms delay before triggering. There is both atemperature high and temperature low limit, and if the actual temperature
exceeds either of these limits, the output will be shut off. Likewise, both high andPage 18 · 4400 Series LaserSource User’s Manual

low limits exist for the sensor (R limits), and the output will be shut off if thesensor measurement exceeds either of these limits, as determined by settings in
the Output Off Menu.
Status Messages
The instrument will display status messages indicating several different
conditions that may be of interest to the user. If multiple conditions exist
simultaneously, then the instrument will cycle through each condition, displaying
each status message for approximately one second.
Possible condition messages are:
Status
LoBW
HiBW
Pulse
ExtTrig
Burst
DLock
Shrt
ILim
ImLim
PoLim
VPEAK

When showing, indicates
The unit is in Io (LoBW) mode.
The unit is in Io (HiBW) mode.
The unit is in Io (Pulse) mode.
The unit is in Io (Ext Trig) mode.
The unit is in Io (Burst) mode.
An interlock triggered by a digital input is open andthe unit cannot be turned on.
A short circuit has been detected on the output.
The unit is in current limit.
The unit is in photodiode current limit.
The unit is in photodiode power limit.
High peak voltage detected

Notice that the mode indicators are in reverse text and are used to highlight theoperating mode.

Settings and Menus
All parameters of the LaserSource can be viewed and changed within themenu. To change any setting, press Menu to enter the menu then rotate theknob to select the parameter to change. Press the knob to begin changing thevalue. You will see an asterisk appear next to the value to indicate that you are inedit mode. Once you have made your change, press the knob or Menu button
to store the value. Pressing the Menu button will store and exit the menu, whilepressing the knob will store the value but leave you in the menu to makeadditional changes.
Some settings are contained inside a sub menu, such as communications
settings. To access the sub menu, simply press the knob to enter the sub menu
when its name is displayed.

4400 Series LaserSource User’s Manual · Page 19

When the Main Display is showing any other screen except the Pilot Laser,pressing Menu will enter the main laser menu. To enter the pilot laser menu, firstswitch to the Pilot Laser screen then press the Menu button.

Main Laser Menu
Menu

Description

Factory
Default

Top Level Menu

Mode

As described in the Control Modes section, theunit offers seven control modes: Io (ACC), Io
HiBW (ACC), Io (Pulse), Io (Ext Trig), Io (Burst),
Im (AMC), Po (APC), and Vf (AVC). Change thissetting to select a new mode.

Range

Selects the high or low current range.

Low

Bandwidth

Selects the bandwidth when operating in Io
HiBW mode. Only available when in Io HiBW
mode.

Max

Io ResResolution of the Io set point and measurement.
Available options are dependent on the range ofthe instrument.

Depends on
model

QCW Const

When in Io (Pulse) or Io (Burst) mode, thiscontrols which parameter (frequency or duty
cycle) is adjusted when the pulse width isadjusted. This setting will only be displayedwhen in Io (Pulse) or Io (Burst) modes.

Freq

QCW Width

Sets the pulse width in QCW mode. See QCW
Mode section for more details. This setting will
only be displayed when in Io (Pulse), Io (ExtTrig), or Io (Burst) modes.

0.1ms

QCW Duty

Sets the duty cycle in QCW mode. See QCW
Mode section for more details. This setting will
only be displayed when in Io (Pulse) or Io(Burst) modes.

10%

QCW Freq

Sets the frequency of the QCW pulse. See QCW
Mode section for more details. This setting will
only be displayed when in Io (Pulse) or Io(Burst) modes.

1000 HzQCW Pulses

Sets the number of pulses to generate when in
Io (Burst) mode. This setting will only bedisplayed when in Io (Burst) mode.

1

Io (ACC)

Page 20 · 4400 Series LaserSource User’s Manual

Factory
Default

Menu

Description

QCW Low

Sets the low (or off) current for QCW pulses.
Setting to zero will use the minimum allowable
pulse current, which will typically only be a few
milliamps.

0.00 AQCW Risetime

Selects the pulse risetime when operating in
QCW mode. Only available when in QCW
mode.

Min

DelayIn

Sets the delay, in seconds, from the start oftrigger input pulse to the start of the current
pulse. This setting will only be displayed whenin Io (Ext Trig) mode.

0.000025s

DelayOut

Sets the delay, in seconds, from the current
pulse to the start of the trigger output pulse.
This setting will only be displayed when in Io(Pulse), Io (Ext Trig), or Io (Burst) modes.

0.000000s

Io limit

This setting controls the maximum amount offorward current that can be delivered to thelaser diode. This limit is implemented in
hardware for immediate response. For more
information about limits, see Using Limits
section.

Maximum

Im limit

This setting controls the maximum amount ofmonitor photodiode current the unit will allow.
This limit is implemented in software. For more
information about limits, see Using Limits
section.

Maximum

Po limit

This setting controls the maximum amount ofmonitor photodiode power the unit will allow.
This limit is implemented in software. For more
information about limits, see Using Limits
section.

Maximum

Vf limit

This setting controls the maximum amount offorward voltage that can be delivered to thelaser diode. This limit is implemented in
hardware for immediate response. For more
information about limits, see Using Limits
section.

Maximum

Vf Sense

Selects the remote voltage sense lines for diodevoltage measurement. Pins 4 & 5 of the Monitor/ Interlock connector must be wiring to thediode. See Using Remote Voltage Sense section
for more details.

Local

4400 Series LaserSource User’s Manual · Page 21

Factory
Default

Menu

Description

Vf Sense Warn

When operating in remote voltage sense mode,
if the remote voltage is significantly lower thatthe voltage at the Output connector, a warning
message is displayed. Only available when Vf
Sense is set to Remote.

No

Cable R

The cable resistance, in ohms. This setting canbe used to compensate for voltage losses in thecable due to cable and connector resistances.
Cable R is ignored in Vf (AVC) Mode. For more
information about this feature, see Using theCable R Setting section. Not available whenusing remote voltage sense.

0.0000 Ω

Int Contact

Enables or disables intermittent contact. Not
available in Io (Pulse), Io (Ext Trig), or Io(Burst) modes

PD RespThis factor is used by the unit to convert frommonitor photodiode current into optical power.
The value is in terms of microamps per milliwatt(μA/mW), such that power = photodiode current
divided by the factor.

PD BiasThis is the photodiode bias voltage, which isapplied to the PD+/PD- pins of the output
connector.

5.0V

On Delay

The delay, from the time the Output button ispressed to when the output is actuallyenergized.

3000msOff

0.00μA/mW

Aux Sensor Menu
ThermA

The A term in the Steinhart-Hart equation for
use with auxiliary sensors.

1.12924E-03

ThermB

The B term in the Steinhart-Hart equation for
use with auxiliary sensors.

2.34108E-04

ThermCThe C term in the Steinhart-Hart equation for
use with auxiliary sensors.

0.87755E-07

T# Lo Lim

Low temperature limit for Aux Sensor 1, 2 or 3

-99°C

T# Hi LimHigh temperature limit for Aux Sensor 1, 2 or 3

125°C

R# Lo LimLow resistance limit for Aux Sensor 1, 2 or 3

0.01kΩ

R# Hi LimHigh resistance limit for Aux Sensor 1, 2 or 3

45kΩPage 22 · 4400 Series LaserSource User’s Manual

Menu

Description

Factory
Default

Digital I/O Menu
Di1 Func

Selects the action to perform when Digital Input
1 is true.

None

Di1 Invert

Inverts the active state of Digital Input 1.

No

Di2 Func

Selects the action to perform when Digital Input
2 is true.

None

Di2 Invert

Inverts the active state of Digital Input 2.

No

Do1 Func

Selects what status is used to control Digital
Output 1.

Off

Do1 Invert

Inverts the state of Digital Output 1.

No

Do2 Func

Selects what status is used to control Digital
Output 2.

Off

Do2 Invert

Inverts the state of Digital Output 2.

No

Relay

Selects what status is used to control the relay.

Off

Func Keys Menu
Key A
and
Key B

The Key A and Key B settings control the action
assignment for the two function keys. See Using
the Function Keys section for additional
information.

None

Communications Menu
Baud

This sets the baud rate for the RS-232 serial
port. See the Computer Interfacing Manual
which is included on the CD that accompanied
this product.

9600

Set While Rmt

To disable changing the set point while in
Remote Mode, set this value to No. To enablechanging the set point while in Remote mode,
set this Value to Yes.

No

Err While Rmt

To turn off the display of errors while in remotemode, set this value to No. To display errors
while in remote mode, set this value to Yes.

Yes

Terminal Mode

Terminal mode simply echoes any characters
received over the serial or USB interfaces.

No

Msg Term

This controls the output message termination,and can be set to CR/LF, CR, LF, or None.

CR/LF

4400 Series LaserSource User’s Manual · Page 23

Factory
Default

Menu

Description

ConfigAllows for restoring the instrument to defaults,
saving configurations, and restoring
configurations. See Saving and Restoring
Configurations for more information.

No Change

Brightness

The vacuum florescent display can be set toone of eight brightness levels.

100%

AutoDim
Display

Automatically dims the display after 1 hour.

Yes

Audible Beep

This setting controls when the unit produces
audible feedback. Set to No to prevent sound,or Yes to enable audible alerts such an error
message.

Yes

Lockout Knob

Lockout knob allows you to disable knob
operation from the main display. This preventsaccidental changes of the set point. The knob
will always work in the menus regardless of thissetting.

No

Knob Speed

Controls the adjustment speed of the knob.
Possible values are slow, medium, and fast.

Slow

System Menu

System Menu ➔ Dig Out Modes
The Dig Out Modes control how to combine the digital I/O signals from themain and pilot laser sections. See Using Digital I/O for more information.
D1 ModeControls how to merge the digital control
signals for the Digital 1 output from the mainand pilot lasers.

Any High

D2 ModeControls how to merge the digital control
signals for the Digital 2 output from the mainand pilot lasers.

Any High

Relay

Controls how to merge the digital control
signals for the relay output from the main andpilot lasers.

Any High

Advanced Menu
Off if T Lim

Enables output shutdown on temperature limit.
Adjusts the OUTOFF register.

Yes

Off if R Lim

Enables output shutdown on resistance limit.
Adjusts the OUTOFF register.

YesPage 24 · 4400 Series LaserSource User’s Manual

Factory
Default

Menu

Description

Off if Io Lim

Enables output shutdown on current limit.
Adjusts the OUTOFF register.

No

Off if Im Lim

Enables output shutdown on photodiodecurrent limit. Adjusts the OUTOFF register.

Yes

Off if Po Lim

Enables output shutdown on photodiode power
limit. Adjusts the OUTOFF register.

Yes

Off on OutTol

Enables output shutdown on out of tolerance.
Adjusts the OUTOFF register.

No

Ramp Time

Sets the ramp time for power up, power down,
and set point changes for Io and Io HiBW
modes.

80ms

Disable Vf Lim

Disables Vf Limit hardware safety (E-505 errors).
Use with caution. See “Optimizing for Pulse
Performance” for more information.

No

V Comp Detect

Disables Voltage Compliance detection (E-537
errors). Use with caution, can result insignificant current overshoots. See “Optimizing
for Pulse Performance” for more information.

Yes

Overcurrent Det

Disabled detection of overcurrent conditions (E541 errors). Use with caution, can result indamage to laser or controller. See “Optimizing
for Pulse Performance” for more information.

Yes

Pilot Laser Menu
To enter the pilot laser menu, first switch to the Pilot Laser screen then press the
Menu button.
Menu

Description

Factory
Default

Top Level Menu

Mode

The pilot laser offers only two control modes: Io(ACC), and Vf (AVC). Change this setting to selecta new mode.

Io (ACC)

4400 Series LaserSource User’s Manual · Page 25

Menu

Factory
Default

Description

Io limit

This setting controls the maximum amount offorward current that can be delivered to the laser
diode. This limit is implemented in hardware for
immediate response. For more information about
limits, see Using Limits section.

Maximum

Vf limit

This setting controls the maximum amount offorward voltage that can be delivered to the laser
diode. This limit is implemented in hardware for
immediate response. For more information about
limits, see Using Limits section.

Maximum

Digital I/O Menu
Di1 Func

Selects the action to perform when Digital Input 1
is true.

None

Di1 Invert

Inverts the active state of Digital Input 1.

No

Di2 Func

Selects the action to perform when Digital Input 2
is true.

None

Di2 Invert

Inverts the active state of Digital Input 2.

No

Do1 Func

Selects what status is used to control Digital
Output 1.

Off

Do1 Invert

Inverts the state of Digital Output 1.

No

Do2 Func

Selects what status is used to control Digital
Output 2.

Off

Do2 Invert

Inverts the state of Digital Output 2.

No

Relay

Selects what status is used to control the relay.

Off

Advanced Menu
Off if MainOn

Enables output shutdown of the pilot laser if themain laser output turned on. Adjusts the OUTOFF
register.

No

Off if T Lim

Enables output shutdown on temperature limit.
Adjusts the OUTOFF register.

Yes

Off if R Lim

Enables output shutdown on resistance limit.
Adjusts the OUTOFF register.

Yes

Off if Io Lim

Enables output shutdown on current limit. Adjusts
the OUTOFF register.

No

Off on OutTol

Enables output shutdown on out of tolerance.
Adjusts the OUTOFF register.

NoPage 26 · 4400 Series LaserSource User’s Manual

Remote Mode Operation
Remote mode operation is when the LaserSource is being controlled by acomputer over the USB or RS232 interfaces. When in remote mode, theLaserSource behaves differently, preventing you from affecting the operation of
the instrument, such as changing the set point. You cannot enter the menu
without taking the unit out of remote mode, and the knob is disabled.
You can exit remote mode at any time by pressing the Menu button, which has
a secondary function to return the LaserSource to local operation.
Details on how to communicate with the LaserSource can be found in theComputer Interfacing Manual which is included on the CD that accompanied
this product.

Installing the USB Drivers
Using the LaserSource via USB is just as simple as using the serial port. In fact,
once you have installed the USB drivers, the instrument will appear as a virtual
serial port that you can use just like a normal serial port.
To install the drivers, simply plug in the instrument to your computer. When the
Add New Hardware wizard appears, insert the CD you received with theLaserSource and follow the on-screen instructions.
Once the drivers are installed, to determine the COM port number, go to Control
Panel and select System. Once the System Properties dialog appears, choose
the Hardware tab then click on the Device Manager button. When the Device
Manager appears, click on the plus sign to the left of Ports. The port identified
as an Arroyo Instruments Virtual COM Port or USB Serial Port is theLaserSource. In the event you have multiple Arroyo Instruments products
plugged in simultaneously, you will need to experiment to see which instrument
was assigned to which port. For example, you could send a *IDN? query andsee which instrument goes into remote mode.

Connecting to the LaserSource
A laser diode is very sensitive to electro-static discharge (ESD), over-voltage,
and over-current conditions. When connecting a laser to the LaserSource,
make sure proper ESD procedures are taken. In addition, it is critical that theproper current limit and voltage limit be set for the laser diode. Exceeding thelaser diode’s rated current or voltage can damage or destroy the laser diode,and the LaserSource’s hardware protection features can only protect the laser
diode if these limits are properly set.

4400 Series LaserSource User’s Manual · Page 27

CAUTION
The interlock connections must be kept isolated from allother connections and from earth ground. Failure to doso may damage the instrument.
The Laser anode and cathode outputs are electrically isolated from ground, as
are the photodiode inputs. In addition, the photodiode inputs are opticallyisolated from the laser outputs, ensuring complete electrical isolation of the drive
circuit and photodiode measurement circuit.

NOTE
Connections to the LaserSource and the laser diodefixture must be secure. Tighten any retaining screws on
all connectors and make sure all connections are ingood condition. Poor or intermittent connections candamage or destroy the laser diode.
Depending on the model, Arroyo Instruments carries cables specificallydesigned for this controller. Contact the factory for more information.
See the manual for your laser (and fixture) for additional safety and operational
information.

Grounding Considerations
A key feature of the LaserSource is the optical isolation of both the photodiodeand modulation inputs. By isolating their inputs, earth grounding of thephotodiode anode or cathode, or earth grounding the modulation input, cannot
cause a ground loop through the instrument. Likewise, the laser anode andcathode connections are also isolated from earth ground.
The However, if you use the earth ground pin of the Output connector (pin A2),
it is possible to create a ground loop if the instrument’s earth ground isconnected to a fixture or optical table that is also earth grounded. Make sure thatfrom your laser diode package there is only a single path to earth ground.

Page 28 · 4400 Series LaserSource User’s Manual

Cable Wiring for Modulation and QCWWhen modulating with square wave signals at any frequency, sine wave at
higher frequencies (>1 kHz) or operating in QCW modes, it is critical that highquality twisted pair cabling with low inductance and capacitance be used, andwire size suitable for the applied current (or the equivalent if using a multiconductor cable). Shielding is recommended for improved noise immunity, but
not required.
See the chart below for suggested sizes. Failure to do so may result in current
oscillations or overshoots that may damage your laser. Reducing wire size by
one or two wire gauges for lower duty cycle pulse operation is generally okay,
although peak voltages and initial current ringing can be significantly higher.
When constructing your own cable out of individual wires, twist the current
carrying wires (LDA and LDC) as tightly as possible. When using large wires
where twisting is impractical, zip-tie every 2” [4cm] or heat shrink to keep thewires as close together as possible.
If in doubt, use a current probe attached to an oscilloscope to monitor actual
performance.
Current (A)
10
20
30
40
60
80
100

Recommend Wire Gauge
16 AWG
14 AWG
12 AWG
10 AWG
8 AWG
6 AWG
4 AWG

For instruments equipped with the 13W3 output connector, the following
CONEC part numbers can be used to build 13W3 cables. Components can befound at Digikey, Mouser, and other electronic components suppliers.
Component
Pin/Socket
D-Sub
Hood

Male End
Female End
131C10039X
132C10039X
131C10049X
132C10049X
3013W3PCM99A10X 3013W3SCM99A10X
952-025-030R121

Wire Size
10-12 AWG
8-10 AWG

Arroyo Instruments’ cables are shielded, twisted-pair cables, and designed tosupport these applications. For questions, contact the factory or your local
representative for additional help.

4400 Series LaserSource User’s Manual · Page 29

Laser Control Modes
The LaserSource offers eight laser control modes:
•
•
•
•
•
•
•
•

Io (ACC) – “eye-oh”
Current set point, automatic current control
Io HiBW (ACC) – “eye-oh-Hi-B-W”
Current set point, high bandwidth mode, automatic current control
Io (Pulse) – “eye-oh-Pulse”
Current set point, internally triggered pulse modeIo (Ext Trig) – “eye-oh-External-Trigger”
Current set point, externally triggered pulse modeIo (Burst) – “eye-oh-Burst”
Current set point, internally or externally triggered pulse trains (one ormore pulses)
Im (AMC) – “eye-M”
Monitor photodiode set point, automatic monitor control
Po (APC) – “P-oh”
Monitor power set point, automatic power control
Vf (AVC) – “V-F”
Voltage set point, automatic voltage control

Changing the control mode is done through the menu by changing the Modeparameter in the menu to one of these values.
Io and Io HiBW modes (referred to collectively as ACC, or automatic current
control modes) are used to drive a specific current through the laser diode. The
LaserSource will drive the desired current set point through the laser diode aslong as the voltage at the chosen set point does not exceed the voltage limit. In
Io mode, you will be limited to less than a 10 Hz bandwidth. To modulate abovethat rate, use the Io HiBW, which is a high bandwidth current mode supporting
modulation. For performance reasons, the system will dissipate more heat when
operating Io HiBW mode. This is to provide the dynamic performance needed
for high frequency modulation signals. Io mode is recommended unlessmodulation is required.
Io (Pulse), Io (Ext Trig), and Io (Burst) are quasi-CW (QCW) modes, where thelaser output is pulsed on based on the pulse width, duty cycle, and frequency,
as defined in the menu. See Using QCW Modes section for more details.
Im mode (also referred to as AMC, or automatic monitor control, mode) is used
to control the laser diode using the photodiode monitor diode feedback. You
select the target photodiode monitor diode current, and the LaserSource will
drive exactly enough forward current through the laser diode to generate thetarget monitor diode current. Only low frequency modulation (10Hz or less) is
possible in Im mode due to the feedback latencies of the photodiode itself.

Page 30 · 4400 Series LaserSource User’s Manual

Po mode (also referred to as APC, or automatic power control, mode) is simply
Im mode with a mathematical constant applied to the set point, providing a
convenient way of operating in milliwatts. Using the PD Resp factor (in μA/mW),a Po set point is internally converted to an equivalent Im set point by the driver,which is then used to control the photodiode feedback. For example, if the PD
Resp factor was 10, then a set point of 1mW would be the same as a set point of
10μA.
Vf mode (also referred to as AVC, or automatic voltage control, mode) is used tocontrol the voltage driven through the device. Unlike ACC mode, AVC mode
allows the current to drive to whatever current is necessary to achieve thevoltage set point, so long as it does not exceed the current limit. As with Im
mode, only low frequency modulation (10Hz or less) is possible in Vf mode.
Modulation
The instrument supports external analog modulation using the Modulation BNC
on the front panel of the instrument. Modulation rates vary by model, so see
your model’s specification for the maximum modulation rates. Only Io HiBW
mode supports high speed modulation. All other modes of operation have amodulation bandwidth of 10Hz or less.

Using QCW Modes
Io (Pulse), Io (Ext Trig), and Io (Burst) are quasi-CW (QCW) modes, where thelaser is turned on and off, typically with very short on times and long off times tominimize the thermal loading of the laser. Measurements are taken only during
the on cycle (although at a reduced accuracy and resolution), and external
instruments can by synchronized using the trigger input and trigger output
signals.
In pulse (Io Pulse) mode, the current pulses are based on the pulse width, duty
cycle, and frequency, as defined in the main menu. To use this mode, set theMode to Io (Pulse), and then set the QCW Width, QCW Duty, and QCW Freq
as needed for your application. These three parameters are interrelated as
defined by the following equation:

Frequency =DutyCycle
PulseWidth

However, if you take the values directly from the menu, then a modified versionof this equation that takes the various decimal places of the menu values into
account could be written this way:

4400 Series LaserSource User’s Manual · Page 31

QCW Freq =QCW Duty*10
QCWWidth

As an example, a 0.6ms pulse width and 30% duty cycle results in a frequencyof 500 Hz. Put into the formula above, it would be written:

500 =

30
*10
0.6

Because of this relationship, when adjusting any of these parameters, it requiresa change in one of the others. To achieve this, when adjusting frequency, duty
cycle is adjusted and when adjusting duty cycle, the frequency is adjusted. For
pulse width adjustments, the frequency or duty cycle is adjusted based on thesetting of QCW Hold. For example, if QCW Hold is set to Duty, then when thepulse width is adjusted, the frequency is adjusted (the duty cycle is held
constant).
In external trigger mode (Io Ext Trig), only the pulse width is defined by the
instrument. The frequency and duty cycle are defined by the trigger input. For
each rising edge of the trigger input, one current pulse will be generated with thepulse width defined by the QCW Width setting.
Burst mode (Io Burst) operates as a combination of pulse and external trigger
modes. Like pulse mode, the pulse train is defined in terms of frequency andduty cycle, but only a specific number of pulses are generated, which can be as
few as one, or as many as 60,000. Like external trigger mode, no pulses are
generated until a trigger is received. As in external trigger mode, this trigger canbe generated from the trigger input, but unlike external trigger mode, it can also
be generated from the front panel using the Output button. When in burst mode,
the BURST icon will be displayed in the upper right corner of the display.
Burst mode operation from the front panel is distinctly different from the otheroperating modes. Normally, you will use the Output button to turn the output onor off. This is true of burst mode, but the Output button does double-duty: it
serves both as an output on/off button as well as a trigger button. To turn the
output on in burst mode, press and hold the Output button for at least one
second, then release. When you release the button, you will hear an audible
click inside the unit, and the blue LED will start flashing. This indicates the output
is ready to start producing pulses. To generate a pulse train, press and release
the Output button quickly (holding it down for less than one second). On the
button release, the pulse train will start. The blue LED will remain lit solid until thepulse train has completed, at which point it will begin flashing again to indicate
it’s ready to start the next pulse train. To turn the output off, press and hold the
Output button for at least one second, then release.

Page 32 · 4400 Series LaserSource User’s Manual

When triggering remotely (or via the LASER:TRIGGER command), the LED will
also remain lit solid during the pulse train. Also, the LASER:OUTPUT commandis only used to turn the output on or off; use the LASER:TRIGGER command to
start a pulse train.
Laser measurements are made just before the falling edge of the pulse,
maximizing the time the laser has to settle. A hardware sample and holdsamples current, voltage, and power simultaneously, ensuring all threemeasurements are made at the same point in time.
Note that QCW mode is not designed to operate below approximately 5% of therange of the instrument. When operating below this point, the accuracy of thepulse degrades, overshoot increases, and the rise time of the pulse increases.
These errors can be overcome somewhat by operating at longer pulse widths,
but actual performance can only be determined through empiricalmeasurements using an oscilloscope and current probe.
QCW Low SetpointA QCW driver will typically generates a square wave output that cycles between
the set point (high state) and zero (low state). The 4400 allows for adjustment of
the low pulse state to operate at a non-zero current (often referred to as the bias
current). This allows QCW operation to operate the laser in such a way thatcurrent is always flowing through the laser, even in the “off” state of the QCWpulse. The QCW Low set point is completely independent of the Io Setpoint – itcan be adjusted to any value from zero to the maximum current of the driver.
During low QCW periods, the output current will be set by QCW Low, while athigh periods, the output current will be set by Io Setpoint (QCW Low does not
add to the set point during the high periods):
Io SetpointQCW Lowtime

To maintain maximum performance, when in the low pulse state, a minimum
current (typically only a few milliamps) will flow. Setting the QCW Low to zero
will reduce the low pulse state current to the minimum possible.
When operating in pulse modes, the Io Setpoint cannot be adjusted below theQCW Low setting. If the Io Setpoint was adjusted below the QCW Low setting
while in a non-QCW mode, when switching to pulse mode the Io Setpoint will
be adjusted up to the QCW Low setting and a W-807 warning message will be
generated to indicate the change.

4400 Series LaserSource User’s Manual · Page 33

Trigger Input and Trigger Output
The Trigger Input and Trigger Output connectors located on the front panel ofthe 4400 can be used to synchronize the 4400 with other instruments. Using the
Trigger Input, another instrument can act as the master, sending a trigger to the4400 to generate a pulse output when in Io (Ext Trig) mode. Conversely, the4400 can act as the master in the system, using the Trigger Output to trigger
other instruments to take a measurement.
The Trigger Input is a 5V input that triggers on the edge of the input pulse. The
pulse should be 1 microsecond or longer.
The Trigger Output is always 10 microseconds wide, positive going pulse thattypically aligns with the start of the current pulse but can be delayed using the
Trigger Out Delay (see below).
Trigger In and Trigger Out Delay
Using the trigger in delay (DelayIn), you can delay the beginning of the current
pulse up to 1 second, and only applies in Io (Ext Trig) mode. Likewise, using
the trigger out delay (DelayOut), you can delay when the trigger output up to 1
second from the start of the current pulse.
When setting the trigger in or trigger out values, another pulse cannot start until
the current pulse (which starts after the trigger input delay) and the trigger
output have both completed. This can limit the range of the frequency or duty
cycle if the trigger delays are large.
For example, if the trigger output delay is 10 milliseconds and the pulse width is
1 millisecond, then the minimum duty cycle is about 10%, because the next
pulse cannot start until after the trigger output is complete.
Risetime Control
The QCW Risetime setting provides the ability to increase the risetime of the
QCW pulse, particularly useful for cable configurations where significant ringing
would otherwise occur. Risetime can be set to Min (fastest risetime), 100μs or
500μs. The latter two times are estimates and may vary slightly depending on
your specific load and cable setup.
See Optimizing for Pulse Performance below for additional information on pulse
operation.

Page 34 · 4400 Series LaserSource User’s Manual

Using Limits
The LaserSource provides several limit features for protection of the laser
diode. These include current, voltage, intermittent contact, photodiode current,
and photodiode power limits.
Both the current and voltage limits are implemented in hardware, providing forfast response to changes in laser diode operation. When a voltage limit isdetected, the output is immediately shutdown. Because of the sensitivity of thevoltage limit, operating near the limit (within one to two hundred millivolts) is notrecommended. In general, you should set the voltage limit to 0.5V to 1V higher
than any anticipated operating point. The voltage limit is tested against thevoltage at the connector, unless in remote voltage sense mode. Any Cable R
value is ignored, as Cable R is a software only calculation, and the voltage limit
is implemented in hardware. See Using the Cable R Setting section for more
information on the Cable R setting.
Unlike the voltage limit, the current limit simply prevents the LaserSource fromdelivering more current than the limit is set to. When the current limit engages,
the output will remain on, unless corresponding bit is set in Outoff register.
The intermittent contact circuit is designed to protect against faulty connections
by detecting fast changes in voltages which can be caused by poor wiring or
faulty connectors. If false trigging of the intermittent contact circuit is frequently
occurring, it can be turned off from the menu.
The photodiode current and photodiode power limits are implemented insoftware and may take up to one second to trigger when these conditions occur,and therefore should not be relied on to provide fast protection of the laser
diode.

Voltage Operating Region
The 4400-80-12 and 4400-100-10 have a maximum power constraint at the
maximum current and maximum voltage operating region. The graph below
details the maximum voltage at a given current limit setting.
If the current limit is raised such that it might result in operation outside theallowable region, the controller will automatically reduce the voltage limit andvoltage set point and generate a W-809 warning message to indicate thechange. To restore operation at a higher voltage limit, reduce the current limit
then adjust the voltage limit.

4400 Series LaserSource User’s Manual · Page 35
13

Maximum Voltage

12
11

10
9
8
7

6
60

65

70

75

80

85

90

95

100

105

Current Limit (Amps)
4400-80-12

4400-100-10

Maximum voltage at a given current limit

Using the Cable R Setting
The Cable R setting allows you to calculate the voltage at the laser by
subtracting the voltage loss through the cable and connectors. This is done bymeasuring or calculating the cable resistance and entering the value, in ohms,
into the menu. The instrument will then use the V = I * R formula to calculate thevoltage loss in the cable and subtract that from the actual measured voltage,displaying the result as Vf on the display.
Common values for Cable R range from 0.0300 Ω to 0.0900 Ω but can besignificantly higher if you have long runs, many connector interfaces, or small
gauge wire.
While it is possible to use a DMM to measure the resistance of the cable,
because resistance is so small, you will not typically get proper readings. A
better approach is to use the instrument to drive current through the system andthen measure the voltage loss to determine resistance. There are two ways tobest calculate the voltage loss:
Measure the Voltage at the Laser
If you have an accurate DMM and can measure the voltage across the laser (oraccurately know the voltage of the laser at a specific current) and voltage acrossthe pins at the Output connector, then the difference between the measured
voltages is the voltage loss in the cable. Use this formula to calculate resistance:

Page 36 · 4400 Series LaserSource User’s Manual

𝐶𝑎𝑏𝑙𝑒𝑅 =𝑉𝑂𝑢𝑡𝑝𝑢𝑡 − 𝑉𝑙𝑎𝑠𝑒𝑟
𝐼

V is in volts, I is in Amps.
Short the Connection at the End of the Cable
A second method, which can be done with just the 4400, is to short the cable atthe end of the cable (nearest the laser diode), drive current through the cableand measure the voltage. The resistance is found using a simpler version of theformula above:
𝐶𝑎𝑏𝑙𝑒𝑅 =𝑉4400
𝐼

Note that the current is expressed in amps, not milliamps. The easiest way is todrive 1 Amp of current. When I equals 1 Amp, the displayed voltage is theresistance of the cable. Another method is to drive 10 Amps of current and thendivide the voltage by 10.
To short the cable, disconnect the laser and short the anode and cathode
together as close to the end of the cable as possible. Ideally, the short should bedone by soldering the anode and cathode wires together to minimize theresistance in the short itself.
How the Calculation Is Used
The 4400 continuously takes the measured current, multiplies it by theresistance (Cable R), subtracts the result from the actual voltage at the output
connector, and displays this value on screen as Vf. However, there are some
limitations to how the cable loss calculation is used:
1.

2.

The value for Vf Limit is always the voltage at the connector (except
when using remote voltage sense, see below). This means that the Vf
Limit must take into account all the voltage required, including thecable loss (i.e., the voltage displayed if the Cable R value were zero).
Cable R is ignored in Vf mode. This means that the set point andmeasured voltage are always the voltages at the connector, and Cable
R is not used.

Using Remote Voltage Sense
The LaserSource also supports remote (4-wire type) voltage measurement of
the laser diode, providing a higher accuracy voltage measurement by directly
measuring voltage at the diode itself. While the Cable R setting described above4400 Series LaserSource User’s Manual · Page 37

can provide some of the same benefits of remote voltage sense, they differ in a
few key ways:
1.
2.
3.
4.

No need to calculate cable resistance
Voltage measurement is accurate even if the cable resistance changes
The hardware safety circuits use the remote voltage, providing for agreater degree of protection (Vf Limit works on the voltage at the laser
rather than the voltage at the connector)
Works in voltage control mode

However, remote voltage sense does have a few drawbacks:
1.
2.

If the remote sense wires are disconnected, it disables the hardware
voltage limit
Requires two additional wires to be run to the device

It is the first of these two drawbacks that is of the biggest concern. In order toprotect against this fault, the instrument monitors the voltage at the connector aswell as the remote voltage, and if the difference is too great, a warning message
is displayed. Once the warning is displayed, it will not be displayed again until
the output is turned off and back on. The warning can be disabled in the menu
by setting the Vf Sense Warn to Off in the menu.
Using Remote Voltage Sense
Using remote voltage sense is very simple. Connect the laser remote sense pins
to the corresponding terminals at the laser, then in the menu, set Vf Sense to
Remote. Indicated voltage will now be the remote diode voltage.
When using remote voltage sense, any Cable R setting is ignored.

Page 38 · 4400 Series LaserSource User’s Manual

Using the Auxiliary Interface
The Auxiliary Interface provides connections to the auxiliary sensors, the digital
inputs and output, an electromechanical relay, and an auxiliary +5V power
supply.
Auxiliary Sensors
Auxiliary sensors are wired for a common ground return, so take care to ensurethat a common ground will not cause interference with other parts of yoursystem. In addition, auxiliary sensors should be electrically isolated from allother signal and power connections on the instrument.

CAUTION
Connecting a sensor signal or sensor ground to any
other signal or power interface could cause damage toyour instrument. Sensors should be fully electricallyisolated from all other connections.
Auxiliary sensor settings can be adjusted in the Aux Sensor menu. The auxiliary
sensors share a common set of Steinhart-Hart coefficients for temperature
conversions.
Each auxiliary sensor has a corresponding high and low temperature limit. By
default, auxiliary sensors that exceed their temperature limits will cause theoutput to shut down. If you want to change this behavior, adjust thecorresponding settings in the Advanced menu. See Working With Thermistors
section for more information on using thermistors.
Auxiliary sensors one and two are found on the Auxiliary DB25 interface. For
non-bus-bar drivers, the 13W3 laser connector features a third sensor input.
Digital Inputs
The 4400 has two digital inputs: Digital Input 1 and Digital Input 2. They share acommon ground with the digital outputs and 5V auxiliary power supply. If left
unconnected, each digital input will be pulled up into an ‘On’ state via internal
pull-up resistors.
Each digital input can be assigned to act as either an additional interlock input, aremote output on/off control, or a trigger input. The logic of the digital input canbe reversed, or inverted, to allow for active low signals. These settings can befound in the Digital I/O Menu » Di# Func and Di# Invert menu entries.

4400 Series LaserSource User’s Manual · Page 39

The digital input is not a high-speed circuit and may take many milliseconds todetect and react to a signal. Therefore, it is not suitable in applications where
high-speed response is required. For high speed triggering, use the Trigger
Input on the front panel on the instrument. Similarly, for high speed interlocks,
use the Chassis or Laser Interlock.
Digital Outputs
The 4400 has two digital outputs: Digital Output 1 and Digital Output 2. They
share a common ground with the digital inputs and 5V auxiliary power supply.
Each digital output can be directly set to be Off (0V) or On (5V), or assigned afunction to control its output state. The available functions are:
•
•
•
•
•

Output On – the digital output will turn on when the output is on
Stable – the digital output will turn on when the instrument is
considered to be stable
T Limit – the digital output will turn on if the temperature limit isexceeded
I Limit – the digital output will turn on if the instrument is operating at its
current limit.
Remote – the digital output will turn on if the instrument is in remotemode.

Each digital output includes a 200Ω series resistor, limiting current draw toabout 25mA. If the output is to be used as a signaling LED, in many cases, an
LED can be directly connected across the digital output and ground.
Each digital output has an invert setting to reverse the state of the output if anactive low signal is required. These settings can be found in the Digital I/O
Menu » Do# Func and Do# Invert menu entries.
Relay
In addition to the digital outputs, the 4400 has an electro-mechanical relay which
can be used as an isolated contact for applications such controlling externalsolenoids for valve control, or powering on an external piece of equipment (1A,
30VDC maximum). Relay control is identical to the digital output control, with allof the same functions available. There is no invert function, but both the normallyopen and normally closed contacts are available, allowing for either polarity to
be wired in.
The N/C (Normally Closed) pin 6 will be closed (shorted) to the common pin 19
when the unit is powered off or when the relay is in the “off” state. Similarly, theN/O (Normally Open) pin 7 will be open (not shorted) to the common pin 19.
When the relay is energized, either by changing the menu setting to On, or whenPage 40 · 4400 Series LaserSource User’s Manual

the assigned function is true, the polarity will reverse: pin 6 will be open (notshorted) and pin 7 will be closed (shorted) to the common pin 19.
Dig Out Modes
The System->Dig Out Modes settings are used to control how to merge thedigital signals generated from the main and pilot laser. Because each channel
independently requests the digital output based on the setting in the Digital I/Omenu, the Dig Out Modes menu settings determine how to resolve conflicts
when the two channels do not match.
Each mode has the following options:
•
•
•
•
•

Off (Open for Relay) – ignore the digital signals from each channel andforce the digital output off (or open the relay).
On (Closed for Relay) – ignore the digital signals from channel andforce the digital output on (or close the relay).
All Low – if both of the digital signals from the main and pilot laser are
low, then turn the digital output on (or close the relay)Any High – if either of the digital signals from the main or pilot laser are
high, then turn the digital output on (or close the relay)All High – if both of the digital signals from the main and pilot laser are
high, then turn the digital output on (or close the relay)

For example, consider the control of the Digital 1 output: if the main laser was
requesting D1 to be high but the pilot laser was requesting low, here is howeach of the above modes would then set the Digital 1 output on the Auxiliary
connector:
Mode Setting
OffOn
All Low
Any Low
All High

Main
D1 OutPilot
D1 OutDon’t care
Don’t care
Don’t care
Don’t care
High
Low
High
Low
High
Low
Example Output States

Auxiliary
Digital 1
Output State
Low (Off)High (On)Low (Off)High (On)Low (Off)4400 Series LaserSource User’s Manual · Page 41

Using the Interlocks
The 4400 has two interlock inputs that can be used to disable the laser output.
The Chassis Interlock is the two-pin green Phoenix connector located next to the
USB connector on the rear of the unit. The Laser Interlock is located either on
the 13W3 connector or the DB-9 Signal connector on units equipped with busbar outputs.
The Interlock inputs are electrically isolated input allowing for safe integration
into both mechanical-type switch closures as well as electronic switches. Bothmust be shorted (or pulled below 4V. It has a pull-up resistor, so if left
disconnected, the interlock status will be “on.” In addition to the dedicatedInterlock input, the digital inputs can also be configured for interlock operation.
See the Interlock section in Using the Auxiliary Interface.

The Laser Interlock/LED Interface
When using the laser interlock without the LED function, simply short the pinsusing a mechanical relay or electronic switch to allow for laser operation.
The laser interlock also can be used to drive an LED to indicate the operatingstate of the laser. When the laser is on, the LED is always on. When the laser isoff, it can be controlled via the computer interface to turn on or flash the LED,
such that it can be used as a signal light to the user.
Closing the Circuit
Inside the controller, a +5V supply is used to bias the LED and goes through a200Ω series resistor. To close the circuit, there must be 4V or less across theinterlock input pins. A short circuit can be used, but an LED can optionally beconnected.
Depending on the type of LED, no resistor, series resistor, or parallel resistor canbe used. Red, green, and yellow LEDs may require no resistor. Blue LEDs are
too efficient to be wired with a series resistor and must use the parallel resistor
option.
When using a series resistor, the higher the resistor value, the dimmer the LED.
Do not use too high of a resistance value or it may always register as an open
circuit.
When using a parallel resistor, the lower the resistor value, the dimmer the LED.
Red, green, and yellow LEDs will typically use higher resistances (1kΩ or more),
while blue LEDs will use smaller resistor values (typically around 100Ω).

Page 42 · 4400 Series LaserSource User’s Manual

The voltage drop must be less than 4V when circuit is complete for properinterlock operation.
+

+

+

–

–

–

Series Resistor

Parallel Resistor

No Resistor

Working With Thermistors
The auxiliary sensor inputs allow for monitoring of a thermistor temperature
sensor, often located in the laser module itself. This sensor can used for simple
thermal monitoring of the diode, and can also be used as a safety by shutting
down the laser diode when temperature limits are exceeded
The LaserSource is designed to work with negative temperature coefficient(NTC) thermistors, such as the BetaTHERM 10K3A1 thermistor used in many of
the Arroyo Instruments LaserMounts and TECMounts. A thermistor works bytranslating temperature into resistance, with resistance decreasing as
temperature increases (hence the ‘negative coefficient’).
Here is a typical response curve of a thermistor:
50000

Resistance (Ω)

40000

30000

20000

10000

0
-10.00

10.00

30.00

50.00
70.00
Temperature (°C)

90.00

Typical Resistance vs. Temperature Graph

110.004400 Series LaserSource User’s Manual · Page 43

As can be seen be the graph, the resistance of the thermistor drops very quickly.
In the typical control range (0°C to 40°C), typical 10K thermistors offer goodsensitivity to changes in temperature, and this is the range in which most 10K
thermistors are typically used. 10K thermistors can be used at much higher
temperatures but will suffer poorer temperature stability performance because of
the lower sensitivity. When evaluating the performance of a thermistor, it isimportant to understand the resistance sensitivity of the thermistor at yourapplication temperature, which varies greatly by temperature and thermistor
types.
The LaserSource supports an upper measurement range of 45kΩ. For most
10K thermistors, this translates into a low-operating range of approximately -7°C
before a sensor open error is indicated. Different thermistor types can be used if
a different measurement range is required.
The Steinhart-Hart Equation
As can be seen from the temperature versus resistance graph above, resistancevaries inversely with temperature in a non-linear fashion. This relationship can be
accurately modeled by polynomial equations, and one such being the SteinhartHart equation:

1= A + B * ln( R) + C * ln( R)3T
The coefficients A, B, and C can usually be obtained from the thermistor
manufacturer. The LaserSource defaults to the coefficients for the BetaTHERM
10K3A1 thermistor (A = 1.12924x10-3, B = 2.34108x10-4, C = 0.87755x10-7).
Temperature limits, as well as the Steinhart-Hart coefficients can be set in the
Aux Sensor menu.

Page 44 · 4400 Series LaserSource User’s Manual

Analog Modulation
The analog modulation input allows for external control of the current set point
using a ±10V analog signal. 10V equals the maximum operating range, which isdependent on the model. For example, a LaserSource which has a maximum
output current of 40 Amps, a modulation input of 5V would equal 20 Amps
output (the “transfer function” is 4 A/V).
In addition, the set point adds to the modulation input, so using the same
example, if you were to apply 5V and the set point was 5 Amps, then the
resulting drive current would be 25 Amps (5 V = 20 A plus the 5 A set point).
You must also consider that the modulation input is not a precision input, so for
accurate current control, you should calibrate the modulation input using a one
point or two-point calibration and apply the calibration to your voltage input. You
can read actual current using the LAS:I? query.
The modulation input on the 4400 supports bipolar modulation (not all Arroyo
Instruments controllers do). Therefore, a negative modulation input will result ina subtraction from the set point.
It is not recommended to modulate the instrument in such a way that the
combination of the instrument set point and modulation input would result in atarget set point below zero. Doing so will not damage the laser or the instrument
but can cause significant waveform distortion as the signal transitions from thenegative to the positive set point region.
When modulating with square wave inputs or at higher frequencies (>1 kHz), it
is critical that high quality, shielded twisted pair cabling be used, and wire size
suitable for the applied current (or the equivalent if using a multi-conductor
cable). Failure to do so may result in current oscillations or overshoots that may
damage your laser. When operating in these modes, always use shielded cableand never use individual wires to connect the instrument to your laser. If in
doubt, use a current probe attached to an oscilloscope to monitor actual
performance.
When modulating with a square wave input, if high peak voltages are detected
due to poor cable configuration, the instrument the instrument will alternate thecurrent measurement with the peak voltage measurement (Vpk) and also
display a _VPEAK_ icon. Note that sine wave operation may also trigger thiscondition if there is significant cable resistance, but if thermal overload errors are
not being generated (E-537), it can safely be ignored.

4400 Series LaserSource User’s Manual · Page 45

Optimizing for Pulse Performance
The LaserSource is a high-power instrument that requires an understanding ofproper setup when operating the unit in pulse mode, either via with a squarewave signal into the analog modulation input or in QCW mode.
CablesThe most critical aspect of your setup is the cable connecting the LaserSource
to your device. You should use the shortest possible wires, particularly in highcurrent applications, and avoid the use of connectors. Poor cables can result insignificant voltage spikes at the leading edge of the pulse which causesignificant overshoot and ringing of the current waveform as well as challenging
thermal management conditions for the 4400.
To start, ensure you are working with a wire gauge that is adequate for theapplication. Review the Cable Wiring section above for recommend wire sizes.
In addition to wire guage, it is highly recommended to use twisted-pair wire, asthat can have an even bigger impact on pulse performance. Consider the twopulses below. Pulse is voltage (1 volt per division), green is current (10 Amps
per division). Both use 12 AWG stranded wire, 24 inches [60cm] in length, but
the wires in the right pulse are twisted, approximately one twist every 2 inches[5cm]). The current waveform is much cleaner and the voltage overshoot is far
less.

In addition to poor waveform performance, high peak voltages can also cause
one of two error conditions: excessive power loads inside the LaserSource,
resulting the driver turning itself off and generating an E-537 thermal error; orinsufficient compliance to meet the peak voltage, resulting in the E-540
headroom violation. In either case, the driver will shut down the output toprevent damage to the driver or the laser.

Page 46 · 4400 Series LaserSource User’s Manual

Lowering BW or Risetime
When using cables that are not well suited for high performance modulation, the4400 includes settings to lower the bandwidth or risetime and virtually eliminate
current overshoot or ringing but at the sacrifice of lower BW or rise time.
••

In Io HiBW mode, a Bandwidth setting allows for the lowering of the
bandwidth from maximum (“Max”) to 3kHz or 0.7kHz.
In pulse modes, a QCW Risetime setting allows for the reduction ofrisetime from the minimum possible (“Min”) to approximately 100μs or
500μs.

Lowering the appropriate setting will generally tame even the worst cablearrangement.
Dead Shorts
The 4400 is a high-performance laser diode driver and not designed to drive
very low resistance loads in pulse mode. Driving a dead short can result in very
high current oscillations and should always be avoided. An E-541 error is anindication of oscillation problems.
Eliminating E-537 (Thermal Overload) Error
The E-537 error is always associated with a large difference between the peakvoltage and the nominal voltage. When the peak voltage is significantly above(more than 2 volts) the nominal operating voltage, the instrument will alternate
the current measurement with the peak voltage measurement (Vpk) and also
display a _VPEAK_ icon. Higher differences indicate poorer cable interfaces andtherefore the possibility of higher current overshoots when operating in squarewave modulation or QCW modes. Equally important, it forces the instrument tooperate with a higher supply voltage, resulting in additional heat being
generated inside the 4400. If the amount of heat being generated exceeds aninternal limit, the E-537 error is generated.
The E-537 error can be prevented in one of three ways:
1.
2.
3.
4.

Improve the wire harness – by switching to a twisted pair cable,
eliminating connectors, and shortening the wires, you will reduce thecapacitance and inductance that causes the higher peak voltages.
Lower the duty cycle – by operating with a lower duty cycle, the thermalload is reduced by a similar amount.
Lower the set point – like lowering the duty cycle, lowering the current
will reduce the thermal load by a similar amount.
Increase risetime (if pulse modes) or lower bandwidth (if modulating)via QCW Risetime or Bandwidth settings, respectively.

4400 Series LaserSource User’s Manual · Page 47

Eliminating E-540 (Voltage Headroom) Error
The E-540 error is caused when the difference between the peak voltage and the
supply voltage drops below an internal safety limit. While the cause of the error
is different than an E-537 error, the same methods above can be used to preventthe error. E-540 errors can be disabled with the V Comp Detect setting, more
information below.
Eliminating E-505 (Voltage Limit) Error
Because of the peak voltages that are generated in pulse modes, the voltage
limit will typically need to be set higher than normal as compared to CW mode.
In CW mode, voltage limits should be set 0.5V to 1V higher than the typicaloperating voltage of the laser. In modulation or QCW modes, the voltage limit
needs to be higher than the peak voltage, which can be several volts above
nominal, depending on the current.
Increasing the voltage limit does not significantly reduce the safety protection forthe laser, as even the maximum voltage limit provides good open-circuit
detection. In some cases, particularly with high compliance loads and highcurrents, E-505 errors may be generated at even the maximum voltage limit. In
that case, follow the guidelines above for eliminating the E-537 error. E-505
errors can be disabled with the Disable Vf setting, more information below.
Eliminating E-541 (Excessive Current Detected) Error
This error indicates a dangerous oscillation condition caused by very low
resistance loads, such as dead shorts or highly inductive loads, and can destroy
sensitive laser diodes. Depending on the frequency and magnitude of theoscillation, the driver may not detect this condition.

CAUTION

E-541 errors indicate a serious fault condition that can
indicate possible damage to a laser diode due tosignificant over-current conditions. Extreme care needs
to be taken in diagnosing this fault before reenergizing
the laser output.
The driver will typically protect itself from physical damage, but the cable andload should be carefully inspected before turning the output back on, startingwith a set point of zero and slowly ramping back to the operating point. If in
doubt, contact the factory for assistance. This warning can be disabled byturning the Overcurrent Det setting in the Advanced Menu to No, but thisshould only be done on advice of the factory.

Page 48 · 4400 Series LaserSource User’s ManualNoise
On some controllers, lowering the voltage limit will allow for the power supply tooperate at a lower voltage and reduce current noise. This is particularly true forlow compliance loads operating on high compliance drivers. In general,
operating with the voltage limit as low as possible without generating E-505
errors will provide the best possible noise performance.
Voltage Limit / Headroom Disable
E-505 and E-537 errors can be disabled via settings in the Advanced Menu but
should be used with extreme caution. Disabling either can result in
unpredictable performance but will allow the controller to operate outside its
normal operational parameters which may be useful in some applications.
Review your requirements with the factory before changing either of thesesettings.
•

V Comp Detect – when set to Yes, the instrument will monitor the peakand supply voltages and ensure the voltage compliance is high enoughto provide sufficient operating headroom. This can be disabled by
setting V Comp Detect to No.

CAUTION

Disabling voltage headroom monitoring can result insignificant current overshoots and should only beenabled on advice of the factory or after verification of
performance with a high speed current probe.
•

Vf Disable – when set to No, the voltage limit hardware circuit will
operate normally. When set to Yes, the voltage limit hardware circuit will
be disabled and the output allowed to operate even if the limit isexceeded. This should only be enabled on advice from the factory.

4400 Series LaserSource User’s Manual · Page 49

Using the Pilot Laser
The 4400 includes an additional low-power driver for controlling a pilot (oraiming) laser that is often included inside high-power laser modules.
With both current and voltage mode operation and a wide current and voltage
range, the pilot laser driver meets the requirements of most pilot lasers.
While the prior portions of the manual were written for the main laser output,
many of the same concepts and capabilities apply to the Pilot Laser driver:•••Hardware current limit
Software monitored voltage limit – while it does not have the speed of a
hardware voltage monitor, the software voltage monitor will shut down
the pilot laser within a few hundred milliseconds of an over-voltage
condition.
Digital I/O and auxiliary sensor interface

Further, the pilot laser driver can be enabled for automatic shutdown when main
laser turns on (see Advanced->Off if Main On in the Pilot Laser menu).
To enter the Pilot Laser menu, you must first press the Display button until the
Pilot Laser screen is displayed and then press the Menu button. Accessing themenu from any other main screen will enter the main laser menu.

Using the Function Keys
The 4400 offers a unique capability: the ability to assign functions to front panelkeys, allowing powerful configuration abilities at the touch of a button. There are
two programmable function buttons.
The function keys can be assigned either of the following actions:••

Run a script
Load a stored configuration

Running a script
The most powerful capability of the function keys is the ability to executecommand strings, or scripts. These scripts are made up of commands, as
defined in the Computer Interfacing Manual, and can affect virtually the entire
operation of the instrument. Any command (except DELAY, *WAI, SCRIPT:GO,or SCRIPT:PUT commands) can be used to construct a script, allowing you to
configure the instrument, change modes, change set points, turn outputs on oroff, or any other of a wide range of actions. Script creation must be done over

Page 50 · 4400 Series LaserSource User’s Manual

the computer interface, see the Computer Interfacing Manual for more
information on how to construct and store scripts.
Because the 4400 is a multi-channel controller, if you are including any laser
commands in the script, be sure to include a LAS:CHAN command at the start ofthe script to specify which channel the script should run against.
Loading a previously stored configuration
Using the System Menu » Config menu item, or the *SAV command over thecomputer interface, up to four different configurations can be saved to memoryand can then be assigned as a recall function. For example, consider anapplication where different laser and/or temperature set points are used. Bysaving the different configurations, you can then assign the recall of theconfigurations to a function key, allowing you to switch between different setups
or set points with a single button press.
Prior to configuring the function keys, you need to create your configurations or
scripts. Configurations are easy: simply setup the instrument the way you want,then go to System Menu » Config to store the configuration into one of the four
configuration bins. Repeat the process for each setup you want to recall.
Scripts are a bit more difficult, as you need to create them using the computerinterface. See the Computer Interfacing Manual for more information on how toconstruct and store scripts.
Once your configurations and scripts have been created, go to Func Key Menu
» Key A and assign a recall configuration or execute script function. You will only
be allowed to select the scripts and configurations you have created.
--- Function Menu -«Return to Main Menu
Key A= Recall Cfg 1
Key B=
None
Func Key Menu
Once actions have been assigned to keys, return to the main screen. To initiate
the action assigned to the A or B keys, press and hold the A or B key until the
instrument does a double beep (approximately one second). This indicates theaction has executed.

4400 Series LaserSource User’s Manual · Page 51

User Calibration
The LaserSource supports the ability to apply a user calibration to allmeasurement and control functions of the instrument. This allows for fieldcalibration of the instrument as needed to meet the requirements of the user’s
application.

NOTE
Changing the user calibration parameters directly
modifies the performance of the instrument. Usercalibrations should only be performed by individuals
experienced in instrument calibration.

NOTE
Ensure that the standards used to calibrate theinstrument exceed the instrument’s specifications. A test
uncertainty ratio of 4:1 or better is recommended, unlessotherwise required by your application.
User calibration can only be performed by sending appropriate commands tothe instrument over the computer interface (either USB or RS232). The
commands are more fully documented in the Computer Interfacing Manual, but
the essential commands are:LASER:USERCAL:EDIT
Enabled modification of user calibration settings
LASER:USERCAL:PUT
Changes user calibration settings
LASER:USERCAL:GET
Retrieves user calibration settings
LASER:USERCAL:RESET Resets all user calibration settings to factory defaults

NOTE
For the sensor, the calibration is applied to themeasurement of the sensor, not the temperature. To
adjust the resistance-to-temperature conversion, change
the sensor coefficients as needed.
To prevent accidental modification of the calibration settings, the entries are only
editable when LASER:USERCAL:EDIT 1 command is sent remotely. By default,Page 52 · 4400 Series LaserSource User’s Manual

M and B values are 1.000 and 0.00, respectively, but can be adjusted to change
the sensor measurement. The calibrated measurement is computed as follows:
User calibrated reading = M * reading + B
For set points, the set point is calculated as follows:
User calibrated setpoint = M * set point + B
B is always in the units of the measurement (for example, volts for laser voltage,etc.).

4400 Series LaserSource User’s Manual · Page 53

Specifications
10A to 20A Unit Specifications
Description

4400-10-56

4400-15-28

4400-20-48

0 – 100.00050.05 + 0.005
10
50
< 15
< 20
56 / 524560

0 – 150.00050.05 + 0.0075
10
50
< 25
< 30
28
420

0 – 200.001
0.05 + 0.01
10
50
< 25
< 40
48
960

25 – 20000
10.05 + 2
200
200
0 to -5V

25 – 20000
10.05 + 2
200
200
0 to -5V

25 – 20000
10.05 + 2
200
200
0 to -5V

0 – 56 (524)0.001
0.05 + 0.005
< 50
< 100

0 – 280.001
0.05 + 0.005
< 50
< 100

0 – 480.001
0.05 + 0.005
< 50
< 100

0 – 10V, 10kΩ
12 to 15

0 – 10V, 10kΩ
15

0 – 10V, 10kΩ
12 to 150.001
0.05 + 0.005

0.01
0.05 + 0.008

0.01
0.05 + 0.010

0.001
0.05 + 0.005

0.001
0.05 + 0.005

0.001
0.05 + 0.005

1
0.05% + 2

1
0.05% + 2

1
0.05% + 2

0.75 – 10
0.00050.1 + 0.010
52

1.13 – 15
0.00050.1 + 0.015
28

1.50 – 20
0.001
0.1 + 0.020
48

0.01

0.01

0.01

CW Specifications
SETPOINTLASER CURRENT
Range (A)Max Resolution (A)Accuracy (±[% set+A])
Stability (± ppm, 1 hour)
Temperature Coeff (± ppm/°C)
Noise/Ripple (mA rms)2
Transients (mA)3Compliance Voltage (V)Maximum Deliverable Power (W)
PHOTODIODE CURRENT
Range (μA)
Resolution (μA)
Accuracy (±[% set+μA])
Stability (± ppm, 24 hours)
Temperature Coeff (± ppm/°C)
PD Bias (V)LASER VOLTAGE
Range (V)Resolution (V)Accuracy (±[% set+V])
Stability (± ppm, 1 hour)
Temperature Coeff (± ppm/°C)
EXTERNAL MODULATION
Input Range / Impedance
Modulation Bandwidth (kHz)5MEASUREMENTLASER CURRENT
Resolution (A)Accuracy (±[% reading+A])
LASER VOLTAGE
Resolution (V)Accuracy (±[% reading+V])
PHOTODIODE CURRENT
Resolution (μA)
Accuracy (±[% reading+μA])

QCW Specifications6
SETPOINTLASER CURRENT (ACC)
Range (A)7
Max Resolution (A)Accuracy (±[% set+A])
Compliance Voltage (V)MEASUREMENTLASER CURRENT
Resolution (A)Page 54 · 4400 Series LaserSource User’s Manual
Description

4400-10-56

4400-15-28

4400-20-48

Accuracy (±[% reading+A])
LASER VOLTAGE
Resolution (V)Accuracy (±[% reading+V])
PHOTODIODE CURRENT
Resolution (μA)
Accuracy (±[% reading+μA])
QCW PARAMETERSPULSE WIDTH
Range (ms)Resolution (ms)Accuracy (ms)
FREQUENCY
Range (Hz)Resolution (Hz)
Accuracy (Hz)DUTY CYCLE
Range (%)
Resolution (%)
Rise/Fall Times (µs)8Overshoot (%)
Zero Current (A)9
LIMITSLASER CURRENT
Resolution (mA)
Accuracy (±[% set+A])
LASER VOLTAGE
Resolution (V)Accuracy (±[% set+V])

0.1 + 0.010

0.1 + 0.015

0.1 + 0.020

0.01
2 + 0.1

0.01
2 + 0.1

0.01
2 + 0.1

10
2 + 100

10
2 + 100

10
2 + 100

0.1 – 600
0.001
0.015

0.1 – 600
0.001
0.015

0.1 – 600
0.001
0.015

1 – 1000
0.1
0.5

1 – 1000
0.1
0.5

1 – 1000
0.1
0.5

0.1 – 90
0.1
< 15 to 25< 10< 0.020

0.1 – 90
0.1
< 20
<7
< 0.030

0.1 – 90
0.1
< 15 to 25<7< 0.0400.02
1 + 0.05

0.05
1 + 0.075

0.05
1 + 0.1

0.1
1 + 0.2

0.1
1 + 0.2

0.1
1 + 0.2

13W3 Female
On 13W3
DB25 Female

13W3 Female
On 13W3
DB25 Female

13W3 Female
On 13W3
DB25 Female

OUTPUT CONNECTOR
Laser Connector
Pilot/Signal Connector
Auxiliary Connector

4400 Series LaserSource User’s Manual · Page 55

30A and 40A Unit Specifications
Description

4400-30-14

4400-30-28

4400-40-24

0 – 300.001
0.05 + 0.015
10
50
< 15
< 60
14
420

0 – 300.002
0.05 + 0.015
10
50
< 25
< 60
28
840

0 – 400.002
0.05 + 0.02
10
50
< 25
< 80
24
960

25 – 20000
10.05 + 2
200
200
0 to -5V

25 – 20000
10.05 + 2
200
200
0 to -5V

25 – 20000
10.05 + 2
200
200
0 to -5V

0 – 140.001
0.05 + 0.005
< 50
< 100

0 – 280.001
0.05 + 0.005
< 50
< 100

0 – 240.001
0.05 + 0.005
< 50
< 100

0 – 10V, 10kΩ
15

0 – 10V, 10kΩ
15

0 – 10V, 10kΩ
15

0.02
0.05 + 0.015

0.02
0.05 + 0.015

0.02
0.05 + 0.020

0.001
0.05 + 0.005

0.001
0.05 + 0.005

0.001
0.05 + 0.005

1
0.05% + 2

1
0.05% + 2

1
0.05% + 2

2.25 – 30
0.001
0.1 + 0.030
142.25 – 30
0.002
0.1 + 0.030
28

3.00 – 40
0.002
0.1 + 0.040
24

0.01
0.1 + 0.030

0.01
0.1 + 0.030

0.01
0.1 + 0.040

0.01
2 + 0.1

0.01
2 + 0.1

0.01
2 + 0.1

CW Specifications
SETPOINTLASER CURRENT
Range (A)Max Resolution (A)Accuracy (±[% set+A])
Stability (± ppm, 1 hour)
Temperature Coeff (± ppm/°C)
Noise/Ripple (mA rms)2
Transients (mA)3Compliance Voltage (V)Maximum Deliverable Power (W)
PHOTODIODE CURRENT
Range (μA)
Resolution (μA)
Accuracy (±[% set+μA])
Stability (± ppm, 24 hours)
Temperature Coeff (± ppm/°C)
PD Bias (V)LASER VOLTAGE
Range (V)Resolution (V)Accuracy (±[% set+V])
Stability (± ppm, 1 hour)
Temperature Coeff (± ppm/°C)
EXTERNAL MODULATION
Input Range / Impedance
Modulation Bandwidth (kHz)5MEASUREMENTLASER CURRENT
Resolution (A)Accuracy (±[% reading+A])
LASER VOLTAGE
Resolution (V)Accuracy (±[% reading+V])
PHOTODIODE CURRENT
Resolution (μA)
Accuracy (±[% reading+μA])

QCW Specifications6
SETPOINTLASER CURRENT (ACC)
Range (A)7
Max Resolution (A)Accuracy (±[% set+A])
Compliance Voltage (V)MEASUREMENTLASER CURRENT
Resolution (A)Accuracy (±[% reading+A])
LASER VOLTAGE
Resolution (V)Accuracy (±[% reading+V])

Page 56 · 4400 Series LaserSource User’s Manual
Description
PHOTODIODE CURRENT
Resolution (μA)
Accuracy (±[% reading+μA])
QCW PARAMETERSPULSE WIDTH
Range (ms)Resolution (ms)Accuracy (ms)
FREQUENCY
Range (Hz)Resolution (Hz)
Accuracy (Hz)DUTY CYCLE
Range (%)
Resolution (%)
Rise/Fall Times (µs)8Overshoot (%)
Zero Current (A)9
LIMITSLASER CURRENT
Resolution (mA)
Accuracy (±[% set+A])
LASER VOLTAGE
Resolution (V)Accuracy (±[% set+V])

4400-30-14

4400-30-28

4400-40-24

10
2 + 100

10
2 + 100

10
2 + 100

0.1 – 600
0.001
0.015

0.1 – 600
0.001
0.015

0.1 – 600
0.001
0.015

1 – 1000
0.1
0.5

1 – 1000
0.1
0.5

1 – 1000
0.1
0.5

0.1 – 90
0.1
< 15
<7
< 0.060

0.1 – 90
0.1
< 15
<7
< 0.060

0.1 – 90
0.1
< 20
<7
< 0.080

0.1
1 + 0.15

0.1
1 + 0.15

0.1
1 + 0.2

0.1
1 + 0.2

0.1
1 + 0.2

0.1
1 + 0.2

13W3 Female
On 13W3
DB25 Female

13W3 Female
On 13W3
DB25 Female

13W3 Female
On 13W3
DB25 Female

OUTPUT CONNECTOR
Laser Connector
Pilot/Signal Connector
Auxiliary Connector

4400 Series LaserSource User’s Manual · Page 57

60A to 100A Unit Specifications
Description

4400-60-14

4400-80-12

4400-100-10

0 – 600.005
0.05 + 0.03
10
50
< 30
< 120
14
840

0 – 800.005
0.05 + 0.04
10
50
< 40
< 160
12
> 900

0 – 100
0.005
0.05 + 0.05
10
50
< 60
< 200
10
> 850

25 – 20000
10.05 + 2
200
200
0 to -5V

25 – 20000
10.05 + 2
200
200
0 to -5V

25 – 20000
10.05 + 2
200
200
0 to -5V

0 – 140.001
0.05 + 0.005
< 50
< 100

0 – 120.001
0.05 + 0.005
< 50
< 100

0 – 100.001
0.05 + 0.005
< 50
< 100

0 – 10V, 10kΩ
15

0 – 10V, 10kΩ
12

0 – 10V, 10kΩ
120.05
0.05 + 0.030

0.05
0.05 + 0.040

0.05
0.05 + 0.050

0.001
0.05 + 0.005

0.001
0.05 + 0.005

0.001
0.05 + 0.005

1
0.05% + 2

1
0.05% + 2

1
0.05% + 2

4.50 – 60
0.005
0.1 + 0.060
14

6.00 – 80
0.005
0.1 + 0.080
127.50 – 100
0.005
0.1 + 0.100
10

0.01
0.1 + 0.060

0.01
0.1 + 0.080

0.01
0.1 + 0.100

0.01

0.01

0.01

CW Specifications
SETPOINTLASER CURRENT
Range (A)Max Resolution (A)Accuracy (±[% set+A])
Stability (± ppm, 1 hour)
Temperature Coeff (± ppm/°C)
Noise/Ripple (mA rms)2
Transients (mA)3Compliance Voltage (V)Maximum Deliverable Power (W)
PHOTODIODE CURRENT
Range (μA)
Resolution (μA)
Accuracy (±[% set+μA])
Stability (± ppm, 24 hours)
Temperature Coeff (± ppm/°C)
PD Bias (V)LASER VOLTAGE
Range (V)Resolution (V)Accuracy (±[% set+V])
Stability (± ppm, 1 hour)
Temperature Coeff (± ppm/°C)
EXTERNAL MODULATION
Input Range / Impedance
Modulation Bandwidth (kHz)5MEASUREMENTLASER CURRENT
Resolution (A)Accuracy (±[% reading+A])
LASER VOLTAGE
Resolution (V)Accuracy (±[% reading+V])
PHOTODIODE CURRENT
Resolution (μA)
Accuracy (±[% reading+μA])

QCW Specifications6
SETPOINTLASER CURRENT (ACC)
Range (A)7
Max Resolution (A)Accuracy (±[% set+A])
Compliance Voltage (V)MEASUREMENTLASER CURRENT
Resolution (A)Accuracy (±[% reading+A])
LASER VOLTAGE
Resolution (V)Page 58 · 4400 Series LaserSource User’s Manual
Description
Accuracy (±[% reading+V])
PHOTODIODE CURRENT
Resolution (μA)
Accuracy (±[% reading+μA])
QCW PARAMETERSPULSE WIDTH
Range (ms)Resolution (ms)Accuracy (ms)
FREQUENCY
Range (Hz)Resolution (Hz)
Accuracy (Hz)DUTY CYCLE
Range (%)
Resolution (%)
Rise/Fall Times (µs)8Overshoot (%)
Zero Current (A)9
LIMITSLASER CURRENT
Resolution (mA)
Accuracy (±[% set+A])
LASER VOLTAGE
Resolution (V)Accuracy (±[% set+V])

4400-60-14

4400-80-12

4400-100-10

2 + 0.1

2 + 0.1

2 + 0.1

10
2 + 100

10
2 + 100

10
2 + 100

0.1 – 600
0.001
0.015

0.1 – 600
0.001
0.015

0.1 – 600
0.001
0.015

1 – 1000
0.1
0.5

1 – 1000
0.1
0.5

1 – 1000
0.1
0.5

0.1 – 90
0.1
< 25
<7
< 0.120

0.1 – 90
0.1
< 30
<7
< 0.160

0.1 – 90
0.1
< 50
<7
< 0.200

0.2
1 + 0.3

0.2
1 + 0.4

0.2
1 + 0.5

0.1
1 + 0.2

0.1
1 + 0.2

0.1
1 + 0.2

Bus Bar, M6
DB9 Female
DB25 Female

Bus Bar, M6
DB9 Female
DB25 Female

Bus Bar, M6
DB9 Female
DB25 Female

OUTPUT CONNECTOR
Laser Connector
Pilot/Signal Connector
Auxiliary Connector

4400 Series LaserSource User’s Manual · Page 59

General Specifications
PILOT LASERCURRENT
Range (mA)
Resolution (mA)
Accuracy (±[% + mA])
Compliance Voltage (V)Current Limit Accuracy (±mA)
VOLTAGE
Range (V)Resolution (V)Accuracy (±[% + V])
Operating Modes

0 – 500
1
1% + 3
>5
5
0–5
0.01
1% + 0.025
Constant current or constant voltage

AUXILLARY INTERFACETEMPERATURE SENSOR
Range (Ω)
Resolution (Ω)
Accuracy (±[% read+Ω])Relay Limits
Digital I/O +5V Supply
Auxiliary Connector

100 – 45,000
1
0.5% + 10
30VDC, 1A max
150mA Max (all signals)
DB-25 Female

GENERAL
Display Type
Chassis Interlock Connector
Computer Interface
Power
Size (H x W x D) [inches (mm)]10
Weight (lbs [kg])Operating Temperature
Storage Temperature

1.
2.
3.

4x20 VFD
2-pin Phoenix part number 1803578
USB 2.0 (Type B), RS-232 (DB-9 Male)
90 – 240 V, 50 / 60 Hz
3.5 (90) x 12 (305) x 14 (356)
13 [5.9]+10°C to +40°C-20°C to +60°C

All values measured after 1-hour warm-up and at 25°C.
RMS current on resistive load, 350kHz BW, low bandwidth mode, ½ scale, high range
Maximum output current transient from normal operations (e.g. power on-off, current
on-off), as well as accidental situations (e.g. power line plug removal).
4. Lower compliance voltage for HiBW and QCW modes.
5. 25% to 75% sine wave modulation, -3dB point. When specified as a range, higher
load voltages will have lower bandwidths.
6. All QCW specifications taken with short cable directly to laser load.
7. Current set point can adjust to zero (Zero Current specification applies), but QCW
specifications only apply to indicated range.
8. 10% to 90% points at ½ scale into diode load. When specified as a range, higher load
voltages will have higher risetimes.
9. Minimum current during QCW operation.
10. Excluding feet, front panel switches, knob, or key, or rear panel bus bars.

Page 60 · 4400 Series LaserSource User’s Manual

Error Messages
Error
Code

Description

E-100

General Error

E-102

Message too long

E-123

Path not foundE-124

Data mismatch

E-126

Too few or too many
elements

E-127

Change not allowed

E-128

Delay or active script
terminatedE-201

Data out of range

E-202

Invalid data type

E-204

Suffix not valid

E-217

Configuration Recall
failed

E-218

Configuration Save
failed

E-220

Script Save Failed

E-221

Cannot embed script

E-222

Cannot execute script

E-501

Interlock shutdown
outputE-504

Laser current limit
disabled output.

Cause
The error code is non-specific, and is generally
used when no other error code is suitable.
The message is too long to process (USB/Serial
only).
The message used an invalid path command(USB/Serial only).
The message contained data that did not matchthe expected format (USB/Serial only).
The command requires more or less than thenumber of parameters actually supplied.
An attempt was made to change a parameterthat cannot be changed, or is currently readonly.
An executing script, or a *WAI or DELAY
function was terminated before completing.
The message attempted to set a value that wasoutside the allowable range (USB/Serial only).
When trying to parse the message, the data wasin an invalid format (USB/Serial only).
An invalid number base suffix (radix) was
encountered when parsing a number(USB/Serial only).
An attempt to recall a configuration failed. Thiscan be caused if no configuration exists in theselected slot, the slot number is out of range, orif the configuration is corrupted.
An attempt to save a configuration failed. Thiscan be caused if the slot number is out of range,or the configuration memory is corrupted.
An attempt to save a script failed. This can becaused if the script number is out of range, orthe script memory is corrupted.
A script was executed that contained a reference
to another script.
An attempt to execute a script failed. This can becaused if the script number is out of range, noscript exists for the selected index, or the script
memory is corrupted.
The interlock input (pins 1 and 2 of the output
connector) were not shorted when the output
was on.
The laser output was turned off because acurrent limit was detected and thecorresponding bit in the OUTOFF register wasset.

4400 Series LaserSource User’s Manual · Page 61
E-505

Laser voltage limit
disabled output

E-506

Laser photodiodecurrent limit disabled
outputE-507

Laser photodiodepower limit disabled
outputE-509

Laser short circuitdisabled output

E-510

Laser out of tolerance
disabled output

E-511
E-512

Laser control error
disabled output
Power failure

E-514

Laser mode change
disabled output

E-516

Incorrect configuration
for calibration to start

E-517
E-534
E-535

Calibration must havethe output on to start
Po mode selected with
PD Response set tozero
Calibration cancelled

E-536

Intermittent contact
fault

E-537

Thermal trip

E-538

Sensor resistance limit

E-539

Sensor temperature
limit

E-540

Vf Headroom Violation

E-541

Excessive Current
Detected

I-700

Config saved

The laser voltage exceeded the voltage limit andthe output was turned off.
The laser output was turned off because aphotodiode current limit was detected and thecorresponding bit in the OUTOFF register wasset.
The laser output was turned off because aphotodiode power limit was detected and thecorresponding bit in the OUTOFF register wasset.
The laser output was turned off because a shortcondition was detected and the corresponding
bit in the OUTOFF register was set.
The laser output was turned off because an outof-tolerance condition was detected and thecorresponding bit in the OUTOFF register wasset.
A hardware control error was detected which
forced a shutdown of the laser output.
A power failure was detected.
The laser output was turned off because achange in the operating mode of theLaserSource while the output was on.
The LaserSource was not configured properly,
including the mode and output on state, to beable to start the desired calibration process.
The laser output must be on for the calibration
process to start.
Attempted to select Po mode and PD Response
was zero., or LaserSource was in Po mode and
PD Response was set to zero.
The active calibration process was cancelled.
The instrument detected an intermittent contact
and shutdown the laser output. If this is
triggering falsely (such as in a noisy
environment), the intermittent contact detection
can be disabled in the main menu.
Excessive power dissipated inside unit. Lower
voltage limit or add series resistance. See“Thermal Considerations” for more details.
The sensor resistance exceeded the limit setup
in the Aux Sensors menu.
The sensor temperature exceeded the limit
setup in the Aux Sensors menu.
Insufficient voltage compliance was detected.
See “Optimizing for Pulse Performance” formore information.
The driver detected an operating current thatwas more than 25% over the current limit. See“Optimizing for Pulse Performance” for more
information.
Instrument configuration successfully stored.

Page 62 · 4400 Series LaserSource User’s Manual
I-701

Config loaded

I-703

Laser usercal reset

W-800

Remote voltage sense
is low

W-801

Burst Mode, Hold
OutputW-803

User reset to factory
defaults

W-805

User recall turned
outputs off

W-806

No function key
assigned

W-807

Io Setpoint Increased

W-808
W-809
E-992
thru
E-997
E-998
E-999

Vf set/limit lowered in
HiBW and pulsemodes
Vf set/limit lowered,constrained by max
power

Instrument configuration successfully loaded.
The user-provided calibration for the laser
measurements and set points reset by the user.
When in remote voltage sense mode, thecontroller detected a significant difference
between the remote voltage and the voltage at
the connector, which may indicate a problem
with the remote voltage sense connection.
When in Io (Burst) mode, to turn the output on,
the Output button must be held down for at least
one second. If it is held down for less than one
second, this warning message informs the user
than the Output button press did not turn the
output on.
Notification message only: User pressed key
sequence on start-up to reset unit to factory
defaults.
Notification message only: A user configuration
was recalled from memory while the outputs
were on, resulting in the outputs being turned
off.
Notification message only: User attempted to
execute a function key action that was not
assigned.
The Io Setpoint was below QCW Low setting
when switching into pulse mode, the Io Setpoint
increased to the QCW Low setting.
The Vf set point and/or the Vf limit was lowered
due to lower voltages available in highbandwidth and pulse mode.
The Vf set point and/or limit was lowered due topower supply constraints.

Hardware error

A hardware related error occurred. If problem
persists, contact factory.

Command notsupported
Non-specific error

A command was recognized but not supportedby the LaserSource.
A non-specific error was encountered.

4400 Series LaserSource User’s Manual · Page 63

Maintenance and Service
Maintenance
The LaserSource requires no regular maintenance other than productcalibration. To clean the instrument, use cotton cloth that is only damp (not wet)with a light solution of soap and water.
Fuses
Under normal operation, you should never need to replace a fuse. However, ifeither fuse does blow, use only T 250V, 10A, IEC 60127-2 5x20mm metric fuses
as replacements.
If, after replacing the fuse, it continues to blow, immediately discontinue use of
the instrument and contact service for support.
Service
Service and repair for the LaserSource can be obtained by contacting the
distributor from where you purchased the instrument, or directly from Arroyo
Instruments. A complete list of distributors is available on the Arroyo Instruments
web site.
You can contact Arroyo Instruments through one of these methods:
By mail:By phone:
By fax:By email:On the web:Arroyo Instruments
1201 Prospect Street
San Luis Obispo, CA 93401
USA+1 (805) 543-1302+1 (805) 543-1303
support@arroyoinstruments.com
http://www.arroyoinstruments.com

In all cases, Arroyo Instruments requires a return materials authorization (RMA)
number. You must contact Arroyo Instruments and obtain an RMA number prior
to returning your instrument, or the shipment may be rejected and sent back toyou.

Page 64 · 4400 Series LaserSource User’s Manual

Warranty
Arroyo Instruments warrants that this product will be free from defects in material
and workmanship and will comply with Arroyo Instruments’ publishedspecifications at the time of sale for a period of one year from date of shipment.
If found to be defective during the warranty period, the product will either be
repaired or replaced at Arroyo Instruments’ option.
To exercise this warranty, write or call your local Arroyo Instruments
representative, or contact the factory directly at the address given above. You
will be given prompt assistance and return instructions. Send the product, freight
prepaid, to the indicated service facility. Repairs will be made and the instrument
returned freight prepaid. Repaired products are warranted for the balance of theoriginal warranty period or 90 days, whichever first occurs.
Limitation of Warranty
The above warranties do not apply to products which have been repaired or
modified without Arroyo Instruments’ written approval, or products subjected tounusual physical, thermal or electrical stress, improper installation, misuse,abuse, accident or negligence in use, storage, transportation or handling. This
warranty also does not apply to fuses, batteries, or damage from battery
leakage.
THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED ORIMPLIED, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR USE. ARROYO INSTRUMENTS SHALL NOT BE
LIABLE FOR ANY INDIRECT, SPECIAL, OR CONSEQUENTIAL DAMAGESRESULTING FROM THE PURCHASE OR USE OF ITS PRODUCTS.

4400 Series LaserSource User’s Manual · Page 65

EC Declaration of Conformity

EC Declaration of Conformity
I/Weof

Arroyo Instruments
1201 Prospect Street
San Luis Obispo, CA 93401
USA

declare that
4400 Series LaserSource Laser Diode Driver
In accordance with the following directives
EMC Directive: 89/336/EEC
Low Voltage Directive: 73/23/EEC
RoHS Directive: 2015/863/EU
has been designed and manufactured to the following specifications:
EMC Directive Test Standards
EN 61326
Electrical Equipment for Measurement, Control and Laboratory Use EMC
Requirements. This encompasses 10 individual Tests
Low Voltage Directive Test Standards
EN 61010
Electrical Equipment for Measurement, Control and Laboratory Use
Safety Requirements.
This Certificate is the Manufacturer’s Declaration which states that the 4400 Series
LaserSource Laser Diode Driver is Compliant to the above noted EU Directives and are
therefore, eligible to bear the CE MARK.
I hereby declare that the equipment named above has been designed to comply with therelevant sections of the above referenced specifications. The unit complies with all
essential requirements of the Directives.
Paul Corr(NAME OF AUTHORIZED PERSON)

President(TITLE OF AUTHORIZED PERSON)(SIGNATURE OF AUTHORIZED PERSON)

1 June 2020

(DATE OF ISSUE)

Page 66 · 4400 Series LaserSource User’s Manual

UK Declaration of Conformity

EC Declaration of Conformity
I/Weof

Arroyo Instruments
1201 Prospect Street
San Luis Obispo, CA 93401
USA

declare that

4400 Series LaserSource Laser Diode Driver

In accordance with the following U.K. Legislation Regulations:Electrical Equipment (Safety) Regulations 2016
Electromagnetic Compatibility (EMC) Regulations 2016
The Restriction of the Use of Certain Hazardous Substances inElectrical and Electronic Equipment Regulations 2012
has been designed and manufactured to the following specifications:
EMC Directive Test Standards
EN 61326
Electrical Equipment for Measurement, Control and Laboratory Use EMC
Requirements. This encompasses 10 individual Tests
Low Voltage Directive Test Standards
EN 61010
Electrical Equipment for Measurement, Control and Laboratory Use
Safety Requirements.
This Certificate is the Manufacturer’s Declaration which states that the 4400 Series
LaserSource Laser Diode Driver is Compliant to the above noted U.K. Legislation andare therefore, eligible to bear the UKCA MARK.
I hereby declare that the equipment named above has been designed to comply with therelevant sections of the above referenced specifications. The unit complies with all
essential requirements of the U.K. Legislation Regulations.
Paul Corr(NAME OF AUTHORIZED PERSON)

President(TITLE OF AUTHORIZED PERSON)(SIGNATURE OF AUTHORIZED PERSON)

September 27, 2022

(DATE OF ISSUE)

4400 Series LaserSource User’s Manual · Page 67

NOTES:

Copyright © 2022, Arroyo Instruments. All Rights Reserved

P/N 530-1055F