Pico ammeter

Posted on Jan 6, 2013

A very sensitive pico ammeter (â€” 1 V/pA) employs the amplifier in the inverting or current summing mode. Care must be taken to eliminate stray currents from flowing into the current summing mode. It takes approximately 5 for the circuit to stabilize to within 1% of its final output voltage after a step function of input current has been applied

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The internal diodes CR1 and CR2 together with external resistor Rl to protect the input stage of the amplifier from voltage transients.

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