The present invention is a system and method for providing a charge detector that utilizes small feedback capacitors in a low-noise, high-gain, system that combines a differential topology in a solid-state amplifier implemented in a complementary metal-oxide semiconductor (CMOS) process with active reset, thereby achieving high dynamic range and robust operations. A custom optoelectronic system is used to measure gain, and while operating at a sampling frequency of 10 kHz, the active reset extends the dynamic range of the charge detector.