Charge Measurement
I type devices use a converter circuit with a capacitor as the feedback element. The output is the voltage across the capacitor. Using a capacitor to integrate suppresses noise and allows small input currents.
I type devices are good for measuring fast pules and very small currents.
I128
128 Channel Charge Integrator Digital Electrometer
I3200
32-Channel Charge Integrator Digital Electrometer
IC101
Precision Electrometer Digital Current Integrator with High Voltage
I404
4 Channel Charge Integrating Digital Electrometer
I6400
64 + 1 Channel Charge Integrator
I400
4 Channel Biased Input Charge Integrating Electrometer
I128S
128-Channel Electrometer