The IVC102U is a Precision Integrating Amplifier with FET operational amplifier, integrating capacitors and low leakage FET switches. It integrates low-level input current for a user-determined period, storing the resulting voltage on the integrating capacitor. The output voltage can be held for accurate measurement. The IVC102U provides a precision, lower noise alternative to conventional transimpedance operational amplifier circuits that require a very high value feedback resistor. The IVC102U is ideal for amplifying low-level sensor currents from photodiodes and ionization chambers. The input signal current can be positive or negative. TTL/CMOS-compatible timing inputs control the integration period, hold and reset functions to set the effective transimpedance gain and to reset (discharge) the integrator capacitor.