Stanford SR570 Current Preamplifier

Low-noise current preamplifier (Distributed only in Germany.)

Specifications

Input
Inputs Virtual null or user-set bias (±5 V)
Input offset ±1 pA to ±1 mA adjustable DC offset current
Maximum input ±5 mA
Noise See graphs
Sensitivity 1 pA/V to 1 mA/V in 1-2-5 sequence (vernier adj. in 0.5 % steps)
Frequency response ±0.5 dB to 1 MHz. Adjustable front-panel frequency response compensation for source capacitance.
Grounding Amplifier ground is fully floating. Amplifier and chassis ground are available at rear panel. Input ground can float up to ±40 V.
Filters
Signal filters 2 configurable (low-pass or high-pass) 6 dB/oct rolloff filters. -3 dB points are settable in a 1-3-10 sequence from 0.03 Hz to 1 MHz.
Gain allocation  
     Low noise Gain is allocated to the front end for best noise performance.
     High bandwidth Front-end gain is reduced for optimum frequency response.
     Low drift Low bias current amplifier is used for reduced drift at high sensitivity.
Filter reset Long time constant filters may be reset with front-panel button.
Output
Gain accuracy ±(0.5 % of output + 10 mV) @ 25°C
DC drift see table below
Maximum output ±5 V into a high impedance load
General
External blanking TTL input sets gain to zero
External toggle TTL input inverts gain polarity
Rear panel biasing ±12 VDC @ 200 mA, referenced to amplifier ground
Computer interface RS-232, 9600 baud, receive only
Power 100/120/220/240 VAC, 6 watts charged, 30 watts while charging. Internal batteries provide 15 hours of operation between charges. Batteries are charged while connected to the line.
Dimensions 8.3" × 3.5" × 13.0" (WHL)
Weight 15 lbs. (batteries installed)
Warranty One year parts and labor on defects in materials and workmanship
 
Sensitivity
(A/V) 		Bandwidth
(-3 dB)* 		Noise/√Hz** Temp. coefficient
±(%input + offset)/°C		 DC Input
Impedance
             
  High BW Low Noise High BW Low Noise Low Drift (11 to 28 °C) All Modes
10-3 1.0 MHz 1.0 MHz 150 pA 150 pA 0.01 % + 20 nA 1 Ω
10-4 1.0 MHz 500 kHz 100 pA 60 pA 0.01 % + 2 nA 1 Ω
10-5 800 kHz 200 kHz 60 pA 2 pA 0.01 % + 200 pA 100 Ω
10-6 200 kHz 20 kHz 2 pA 600 fA 0.01 % + 20 pA 100 Ω
10-7 20 kHz 2 kHz 600 fA 100 fA 0.01 % + 2 pA 10 kΩ
10-8 2 kHz 200 Hz 100 fA 60 fA 0.01 % + 400 fA 10 kΩ
10-9 200 Hz 15 Hz 60 fA 10 fA 0.025 % + 40 fA 1 MΩ
10-10 100 Hz 10 Hz 10 fA 5 fA 0.025 % + 20 fA 1 MΩ
10-11 20 Hz 10 Hz 10 fA 5 fA 0.040 % + 20 fA 1 MΩ
10-12 10 Hz 10 Hz 5 fA 5 fA 0.040 % + 20 fA 1 MΩ
             
* Frequency Compensation adjusted for flat frequency response
** Average noise in the frequency range below the 3 dB point but above the frequency where 1/f noise is significant