MULTI-SAMPLING IN X-RAY RECEIVER FOR NOISE REDUCTION

摘要

The disclosure provides a receiver with reduced noise. The receiver includes a photodiode that generates an input signal in response to received light pulses. A pixel switch is coupled to the photodiode. An operational amplifier is coupled to the photodiode through the pixel switch. A feedback capacitor and a reset switch are coupled between a first input port and an output port of the operational amplifier. A switched resistor network is coupled to the output port of the operational amplifier. A first switched capacitor network is coupled to the switched resistor network and samples a reset voltage. A second switched capacitor network is coupled to the switched resistor network and samples a signal voltage. A subtractor receives the reset voltage and the signal voltage, and generates a sample voltage. The second switched network comprises two or more capacitors.

主权项

1. A receiver comprising
a photodiode configured to generate an input signal in response to received light pulses; a pixel switch coupled to the photodiode; an operational amplifier coupled to the photodiode through the pixel switch; a feedback capacitor and a reset switch coupled between a first input port and an output port of the operational amplifier; a switched resistor network coupled to the output port of the operational amplifier; a first switched capacitor network coupled to the switched resistor network and configured to sample a reset voltage; a second switched capacitor network coupled to the switched resistor network and configured to sample a signal voltage; and a subtractor configured to receive the reset voltage and the signal voltage, and configured to generate a sample voltage, wherein the second switched network comprises two or more capacitors.