Flicker detection gain control circuit, digital imaging system, and method

摘要

A gain control circuit includes a light detector for generating an amount of current based on received light and a first switch for controlling the amount of current from the light detector delivered to a node. The gain control circuit also includes a charge storage element for providing an amount of capacitance to the node and a second switch for controlling the amount of capacitance provided to the node. The gain control circuit further includes an output interface for delivering an output signal based on the amount of current and the amount of capacitance at the node. The light detector may include multiple photodiodes, and the first switch may include a pair of NMOS switching transistors coupled to at least one photodiode. Also, the charge storage element may include multiple capacitors, and the second switch may include a PMOS transistor and an NMOS transistor coupled to each capacitor.