This version (14 Aug 2017 08:31) was approved by erbe.
CN0273: High Speed FET Input Instrumentation Amplifier with Low Input Bias Current and High AC Common-Mode Rejection
The circuit is a high speed FET input, gain-of-5 instrumentation amplifier (in-amp) with a wide bandwidth (35 MHz) and excellent ac common-mode rejection, CMR, (55 dB at 10 MHz). The circuit is ideal for applications where a high input impedance, fast in-amp is required, including RF, video, optical signal sensing, and high speed instrumentation. The high CMR and bandwidth also makes it ideal as a wideband differential line receiver. Ideal as a wideband differential line receiver.
+/-5V supply should be supplied to the connector for proper operation of the evaluation board
Signal Generator w/ Balanced Differential Drive Source can be used as an input source.
Peak to Peak Input Voltage Restriction
Maximum allowable differential input is ±3.5 V
/G1, where G1 is the gain of the first stage.
There is a tradeoff between the maximum allowable differential input and the closed-loop gain of the first stage.
Common Mode Input Voltage Restriction
Allowable input common-mode range for the composite circuit is from −3.5 V
to +2.2 V
Bandwidth Input Restriction
Oscilloscope can be used to measure the output of the evaluation board with a gain of 14db below 10Mhz input as indicited in the graph below.
The output swing of the circuit is limited to ±3.5 V
when operating on ±5 V
FET Amplifier Input Gain Stage
SCHEMATICS, PCB LAYOUT, BILL OF MATERIALS