International Radiation Detectors, Inc.
PA100
Description
The PA100 is a photodiode amplifier used to counteract the effects of attenuating signal cables on
small signals generated from phtotdiodes. The PA100 accomplishes this function by isolating the
detected photodiode signal from the line inductance and caspacitance typical of coaxial signal cables.
This isolation function allows very small photodiode signals (on the order of 10 fC) to be transmitted
several feet over common 50 ohm coaxial cables without being corrupted by noise pick-up
Features
- AC coupled detector bias network for photodiodes with up
to 1µA of dark current at 50V and up to 500 nF
capacitance. Bias network is bipolar.
- Internal power supply filter network.
- Selectable gains of 1,5,10,50,100,500, 1000 and 5000 X. If
requested, the gain can be remotely selected.
- Integral test capacitor to facilitate charge injection
input for calibration.
- High-speed detector response
Specifications
| Parameter |
Conditions |
Minimum |
Typical |
Maximum |
Units |
| Detector Capacitance |
As attached to PA100 |
- |
- |
500 |
nF |
| Detector dark current leakage |
As attached to PA100 |
-
|
-
|
1
|
µA
|
|
Detector Bias Voltage
|
As attached to PA100 |
0
|
-
|
50 |
V
|
|
Minimum Charge Detection Limit
|
As attached to PA100 |
7
|
10
|
20
|
fC
|
|
Risetime
|
Gain = 5000
|
|
25
|
|
µs
|
|
Maximum Pulse Width
|
As attached to PA100 |
-
|
-
|
62
|
ms
|
|
Noise Figure
|
All bands
|
|
16
|
64
|
nV/(Hz)^(1/2)
|
|
Test Capacitor
|
Integral to PA100 |
9
|
10
|
11
|
pF
|
|
Peak output
|
Saturation distortion
|
|
4
|
|
V
|
|
Power Supply
|
Dual
|
+/- 6 |
+/- 12
|
+/- 17 |
V
|
|