Product Features
CW and pulsed operating modes
Built-in laser diode protection
Adjustable pulse amplitude, pulse
width and duty cycle
Clean precise pulses with <25 ns
rise times and low overshoot (<5%)
Trigger In and Out functions
IEEE488/GPIB instrument interface

Specifically designed to drive low power laser diodes,
the LDP-3811 is a microprocessor-controlled current sourcewith two operational modes, CW or pulsed. Offering adual range 200/500 mA output, it has the flexibility to meeta variety of lower power laser diode testing needs. The
standard GPIB interface with trigger in/out functions allow
complete system integration with other lab equipment, andimprove the accuracy, ease, and speed of data gatheringand remote measurement. The intuitive front panel allows
easy adjustment of CW or pulsed operating modes andparameters.
The LDP-3811 offers complete laser diode protection
and safety features such as current limits and output
shorting circuits, along with operational and power transient
protection.

Precision Pulsed Controlof Low Power Laser Diodes

LDP3811
Precision Pulsed
Current Source

LDP3811
Precision Pulsed
Current Source

Complete System Integration
Remote instrument operation is available on theLDP-3811 through an IEEE488/GPIB interface. All
instrument controls and functions are accessible
through the interface for easy remote programming andcontrol in automated test systems where repeatable
and accurate test sequencing, measurements, anddata handling are required. Whether the applicationis data intensive LIV testing, pulsed control for thermal
characterization, or R&D evaluations, remote operationof the 3811 saves time and ensures systematic datacollection and instrument operation.
TTL level triggers are incorporated into the LDP-3811to control output pulses and to initiate corresponding
measurements from other instruments without acommand program.

CW or Pulsed Operation
The LDP-3811 operates as a dual range current
source in both CW and pulsed mode. High setpoint

accuracy and a low noise stable output current assuresconfidence in laser diode CW or pulsed measurements.
Adjustable current limits, and transient suppression
in any operating mode protect the laser diode undertest.

Adjustable Pulse Parameters
The LDP-3811 is designed for quick and easy
instrument operation permitting precise pulse control.
Pulse modes and parameters are logically grouped
together allowing easy adjustment of pulse width, duty
cycle and frequency. A selection of pulse operating
modes includes constant duty cycle and constantpulse repetition interval (PRI). In constant duty cycle
mode, the set duty cycle is maintained while adjusting
pulse widths. In constant PRI mode, the set pulseinterval is maintained while adjusting pulse width. The
bright 4-digit LED display is easy to view in laboratoryenvironments while precision digital tuning isaccomplished with the front panel adjustment knob.

Specifications
DISPLAYPULSE AMPLITUDE
Range:
Resolution:
Accuracy:2
Temperature Coefficient:Compliance Voltage:
Overshoot50 mA < I < Imax:<50 mA:
Maximum Load:

0–200/0–500 mA, floating110 µA± 0.5% of FS<100 ppm/°C
>25 V
< ±5%
< ±2 mA
50

CW CURRENT OUTPUT
Range:
Resolution:
Accuracy:
Temperature Coefficient:
Short-Term Drift:3
Long-Term Drift:4Compliance Voltage:
Noise and Ripple:
Maximum Load:

0–200/0–500 mA, floating
10 µA±0.5% of FS<100 ppm/°C<100 ppm<200 ppm>25 V<200 µA rms50

PULSE PARAMETERS
Pulse Width
Range:
Resolution:
Accuracy:
Pulse Rise/Fall Time:5
Pulse Repetition Interval (PRI)
Range:
Resolution:
Accuracy:
Duty Cycle:

0.1 µs to >1000 µs
100 ns
10 ns ± 0.01% of reading<25 ns
1 µs to >1000 µs
100 ns
20 ns ± 0.01% of reading
0.01% to 100%

TRIGGER OUTPUT
Type:
Jitter:Delay:TTL
5 ns
40 ns, ±10 ns

TRIGGER INPUT
Type:
Jitter:Delay:TTL
100 ns200 ns, ±20 ns

Type:
Maximum Readings:
Resolution:
Accuracy:

4-digit, green LED
505.0 mA, 1000 µs, 6.500 ms, 100.0%
0.1 mA, 0.1 µs, 0.01%±0.5% of FS

GENERAL
GPIB:
Weight:Size (HxWxD):
Power (50–60 Hz):Operating Temperature:
Storage Temperature:
Regulatory Compliance:

Warm up:
Laser Safety:

IEEE488
5.2 kg (11.4 lbs)
88 mm x 212 mm x 269 mm
3.5" x 8.4" x 10.6"
90–105/105–125/210–230/220–250
0°C–50°C–40°C to 70°C
CE Certified
2004/108/EC; EN61326-1:2006; EN55011:2007
Safety, 73/23/EEC; EN60950, EN61010-1
1 hourInterlock, key switch

NOTES

All specifications measured after a one-hour warm up at 25°C with a 50  load.
1 Grounding the laser diode cathode degrades pulse performance.
2 Measured after 2 µs settling time.
3 Over any 10 minute interval, half scale output.
4 Over a 24 hour period, half scale output.
5 Measured from 10%–90% points at half scale output.
In keeping with our commitment to continuous improvement, ILX Lightwave
reserves the right to change specifications without notice and without liability forsuch changes.

ORDERING INFORMATION
LDP-3811
CC-305S
CC-306S
LNF-320
RM-122
RM-124LabVIEW® 3.0

Precision Pulsed Current SourceCurrent Source/Laser Diode Mount
Interconnect Cable
Current Source/UnterminatedInterconnect Cable
Low Noise Filter
Dual Rack Mounting Kit
Single Rack Mounting Kit
Instrument Driver

For information call
P.O. Box 6310, Bozeman, MT 59771 • FAX: 406-586-9405

1-800-459-9459

www.ilxlightwave.com

International Inquiries: 406-556-2481
email: sales@ilxlightwave.com

Rev.06 022609