Datasheet

DHPCA-100
Variable Gain
High Speed Current Amplifier

28Features

Transimpedance (gain) switchable from 1 x 10 to 1 x 10 V/ABandwidth from DC up to 200 MHz
Upper cut-off frequency switchable to 1 MHz, 10 MHz or full bandwidth
Switchable AC/DC coupling
Adjustable bias voltage for use with external photo detectors
Input protection against ±1.5 kV transients
Local and remote control of all main functions

Applications

Photodiode and photomultiplier amplifier
Spectroscopy
Beam monitoring for particle accelerators/synchrotrons
Ionisation detectors
Preamplifier for A/D converters, HF lock-ins, etc.

Block Diagram

SOPHISTICATED TOOLS FOR SIGNAL RECOVERY
DE-DHPCA-100_R11/MN,LK,JM/25MAR2015

Page 1 of 9

Datasheet

DHPCA-100
Variable Gain
High Speed Current Amplifier

Specifications

Test conditions

VS = ±15 V, TA = 25 °C, load impedance = 50 ΩGain

TransimpedanceGain accuracy

1 x 10 ... 1 x 10 V/A @ 50 Ω load
±1 %Frequency Response

Lower cut-off frequency
Upper cut-off frequency

DC / 100 Hz, switchable
depending on gain setting up to 200 MHz (see table below),switchable to 10 MHz or 1 MHzInput

Equ. input noise current
Equ. input noise voltage
Input bias current

see table below
typ. 2.8 nV/√Hz
typ. 20 pA

Performance depending
on Gain Setting

Gain setting (low noise) (V/A)

1022810310410

5106107

Upper cut-off frequency (–3 dB) 200 MHz 80 MHz
Rise/fall time (10 % - 90 %)1.8 ns 4.4 ns
Input noise current density (/√Hz) 220 pA 17 pA
measured at
1 MHz 1 MHz
Integr. input noise current (RMS)* 4.6 µA 370 nA
Max. input current (±)
10 mA 1 mA
DC input impedance
50 Ω50 Ω
Gain setting (high speed) (V/A)

10310414 MHz
25 ns
2.2 pA1 MHz
20 nA
0.1 mA60 Ω
1053.5 MHz
0.1 µs
490 fA
10 kHz3.0 nA
10 µA
100 Ω
106

1.8 MHz0.2 µs
140 fA
10 kHz0.72 nA
1 µA
1 kΩ
107220 kHz
1.6 µs
51 fA
10 kHz60 pA
0.1 µA
10 kΩ
108

Upper cut-off frequency (–3 dB) 175 MHz 80 MHz
Rise/fall time (10 % - 90 %)2.0 ns 4.4 ns
Input noise current density (/√Hz) 155 pA 6.1 pAmeasured at
1 MHz 1 MHz
Integr. input noise current (RMS)* 2.8 µA 280 nA
Max. input current (±)
1 mA
0.1 mADC input impedance
50 Ω50 Ω

14 MHz25 ns
1.5 pA
1 MHz
18 nA
10 µA
60 Ω

3.5 MHz0.1 µs
440 fA
10 kHz3.0 nA
1 µA
100 Ω

1.8 MHz0.2 µs
140 fA
10 kHz0.72 nA
0.1 µA
1 kΩ

220 kHz1.6 µs
51 fA
10 kHz
60 pA
10 nA
10 kΩ

* The integrated input noise is measured with an open but shielded amplifier input in the fullbandwidth (“FBW”) setting. The measurement bandwidth is 3 x the upper cut-off frequency at thespecific gain setting; filter slope is a 1st order roll-off.
The peak-to-peak noise can be calculated from the RMS noise as follows:
Input referred peak-to-peak noise:
IPP = IRMS x 6
Peak-to-peak output noise:
UPP = IPP x gain
Upper cut-off frequencies and equivalent input noise currents given in this table are typical values
only which will depend on the source capacitance. Keep the source capacitance as low as possible
by using short cables at the input to achieve best possible bandwidth and noise performance. For
the dependence of the upper cut-off frequencies on the source capacitance please see thediagrams on the next page.

SOPHISTICATED TOOLS FOR SIGNAL RECOVERY
Page 2

Datasheet

DHPCA-100
Variable Gain
High Speed Current Amplifier

Specifications (continued)

Frequency response plots

SOPHISTICATED TOOLS FOR SIGNAL RECOVERY
Page 3

Datasheet

DHPCA-100
Variable Gain
High Speed Current Amplifier

Specifications (continued)

Dependence of upper cut-off frequency on source capacitance
1000

Bandwidth [MHz]102 V/A Low Noise
103 V/A High Speed

100103 V/A Low Noise
104 V/A High Speed
101110100

1000100

1000

100

1000

Source capacitance [pF]

Bandwidth [MHz]100104 V/A Low Noise
105 V/A High Speed
10105 V/A Low Noise106 V/A High Speed
1110Source capacitance [pF]

10Bandwidth [MHz]106 V/A Low Noise
107 V/A High Speed
1107 V/A Low Noise
108 V/A High Speed

0,1
0.1

0,01
0.01
1

10
Source capacitance [pF]

SOPHISTICATED TOOLS FOR SIGNAL RECOVERYPage 4

Datasheet

DHPCA-100
Variable Gain
High Speed Current Amplifier

Specifications (continued)
OutputOutput voltage range
Output impedance
Slew rate
Max. output current
Output offset compensation±1 V (@ 50 Ω load), for linear amplification
50 Ω (designed for 50 Ω load)
1,000 V/µs
±40 mAadjustable by offset potentiometer and external control
voltage, output offset compensation range min. ±100 mV

DC Monitor Output

Monitor output gain

ModeMonitor gain
low noisegain setting divided by –1

high speed

gain setting divided by –10

Monitor output polarity
Monitor output voltage rangeMonitor output bandwidth
Monitor output impedance

inverting±1 V (@ ≥1 MΩ load)
DC ... 1 kHz
1 kΩ (designed for ≥1 MΩ load)

Bias voltage range±10 V, max. 22 mA, connected to shield of BNC input
socket, adjustable by potentiometer, switchable to GND

Warning

A bias current of 20 mA may destroy sensitive detectors.
Please pay attention to the correct polarity and careful
adjustment of the bias voltage to protect your detector.
Put the bias switch to GND (ground) if you do not want touse the internal bias voltage. The positive and thenegative supply voltage of the amplifier must be switched“on” and “off” simultaneously in order to avoid
overvoltage at the bias output.

Description

Monitor output polarity
Monitor output voltage range
Monitor output impedance

The signal at the bias voltage monitor output (pin 7 of theSub-D control socket) is identical to the detector bias
voltage present on the shield of the input BNC socket. By
monitoring the signal on pin 7 the desired bias voltage
can be adjusted through the bias potentiometer. Even ifthe bias switch is set to “GND”, the bias voltage can bemonitored and set to the desired value.
non-inverting±10 V (@ ≥1 MΩ load)
1 kΩ (designed for ≥1 MΩ load)

Indicator LED

Function

overload

Digital Control

Control input voltage range
Control input current
Overload output

LOW bit: –0.8 V ...+1.2 V, HIGH bit: +2.3 V ... +12 V0 mA @ 0 V, 1.5 mA @ +5 V, 4.5 mA @ +12 V
non active: <0.4 V @ 0 ... –1 mA
active:typ. 5 ... 5.1 V @ 0 ... 2 mA

Ext. Offset Control

Control voltage range
Offset control input impedance

±10 V
15 kΩ

Power SupplySupply voltage
Supply current±15 V
typ. +110 / –90 mA (depends on operating conditions,recommended power supply capability min. ±200 mA)±12 V, max. 20 mA, +5 V, max. 50 mA

Detector Bias

Bias Voltage Monitor
OutputStabilized power supply output

SOPHISTICATED TOOLS FOR SIGNAL RECOVERY
Page 5

Datasheet

DHPCA-100
Variable Gain
High Speed Current Amplifier

Specifications (continued)
CaseWeightMaterial

320 g (0.74 lb.)
AlMg4.5Mn, nickel-platedTemperature Range

Storage temperature
Operating temperature–40 °C ... +100 °C
0 °C ... +60 °C

Absolute Maximum Ratings

Signal input voltage
Transient input voltage
Control input voltage
Power supply voltage±5 V±1.5 kV (out of a 1 nF source)–5 V / +16 V±20 V

Connectors

Input

BNC, isolated, jack (female)

Output

BNC, jack (female)

Detector bias output

shield of input BNC

Power supply

Lemo series 1S, 3-pin fixed socket(mating plug type: FFA.1S.303.CLAC52)
Pin 1:+15V
Pin 2:–15V
Pin 3:GND®

PIN 2–Vs

PIN 1+Vs

PIN 3
GNDControl port

Sub-D 25-pin, female, qual. class 2
Pin 1:+12 V (stabilized power supply output)
Pin 2:–12 V (stabilized power supply output)
Pin 3:
AGND (analog ground)Pin 4:+5 V (stabilized power supply output)
Pin 5:
digital output: overload (referred to pin 3)
Pin 6:
DC monitor output
Pin 7:
bias monitor output
Pin 8:
output offset control voltage input
Pin 9:
DGND (ground for digital control pins 10 - 16)
Pin 10:digital control input: gain, LSB
Pin 11:
digital control input: gain
Pin 12:
digital control input: gain, MSB
Pin 13:
digital control input: AC/DC
Pin 14:
digital control input: high speed / low noise
Pin 15:upper cut-off frequency limit 10 MHz
Pin 16:
upper cut-off frequency limit 1 MHz
Pin 17 - 25: NC

SOPHISTICATED TOOLS FOR SIGNAL RECOVERY
Page 6

Datasheet

DHPCA-100
Variable Gain
High Speed Current Amplifier

Remote Control Operation

GeneralRemote control input pins are opto-isolated andconnected by a logical OR function to the local switch
settings. For remote control set the corresponding local
switches to “Remote”, “DC”, “L” (low noise mode) and“FBW”, and select the desired setting via a bit code at thecorresponding digital inputs.
Mixed operation, e.g. local AC/DC setting and remotecontrolled gain setting, is also possible.
Switch setting “Bias / GND” is not remote controllable.

Gain setting

low noisehigh speed
Pin 14=LOW Pin 14=HIGH Pin 12
gain (V/A)
gain (V/A)
MSB

Pin 11

Pin 10LSB
210310
410
510
610
7
10
Gain settling time
AC/DC setting

310410510610710810

LOW
LOW
LOW
LOW
HIGH
HIGH

LOW
LOW
HIGH
HIGH
LOW
LOW

Pin 15

Pin 16

LOW
HIGH
LOW
HIGH
LOW
HIGH

<80 mscouplingPin 13

DCAC
Low pass filter setting

LOW
HIGH

upper cut-off frequ. limitHigh speed / low noise setting

full bandwidth
10 MHz
1 MHz

LOW
HIGH
LOWmodePin 14

LOW
LOW
HIGH

low noise mode
LOW

high speed mode

HIGH

SOPHISTICATED TOOLS FOR SIGNAL RECOVERY
Page 7

Datasheet

DHPCA-100
Variable Gain
High Speed Current Amplifier

Application DiagramsPhoto detector biasing through internal bias voltage source
Set bias switch to “Bias”. The photodiode is biased through the amplifier with the bias voltage
applied to the shield of the isolated BNC input socket. The photodiode should be mounted in a
metal case. For optimum shielding the metal case has to be isolated from the photodiode but
connected to the housing of the DHPCA-100.

Photo detector biasing through external voltage source
Set bias switch to “GND”. The photodiode is biased through an external voltage source. The
shield of the isolated BNC input socket is internally set to amplifier GND. The photodiodeshould be mounted in a metal case. For optimum shielding the metal case has to be isolated
from the photodiode but connected to the housing of the DHPCA-100.

SOPHISTICATED TOOLS FOR SIGNAL RECOVERY
Page 8

Datasheet

DHPCA-100
Variable Gain
High Speed Current Amplifier

Dimensions

157 mm

150 mm

15 mm

137 mm

51 mm

OUT
44 mm

INPOWER

28 mm

15 mm

43 mm

Ø 3.2 mm

DZ-DHPCA-100_R3

FEMTO Messtechnik GmbH
Klosterstr. 6410179 Berlin · Germany
Phone: +49 30 280 4711-0
Fax: +49 30 280 4711-11
Email: info@femto.de
www.femto.deSpecifications are subject to change without notice. Information provided herein is believed to be accurate andreliable. However, no responsibility is assumed by FEMTO Messtechnik GmbH for its use, nor for any infringementof patents or other rights of third parties which may result from its use. No license is granted by implication orotherwise under any patent or patent rights of FEMTO Messtechnik GmbH. Product names mentioned may also betrademarks used here for identification purposes only.
© by FEMTO Messtechnik GmbH · Printed in Germany

SOPHISTICATED TOOLS FOR SIGNAL RECOVERYPage 9