Patent ID: 7872682

Claim:
An anti-eclipse circuit for an imager, comprising: a signal storing circuit connected to a column line and for storing a reset signal in a storage element at a first time and for storing a photo signal at a second time, said signal storing circuit comprising: a replacement circuit for receiving a control signal on a control line and for replacing said stored reset signal with a correction signal in the storage element during the second time if said control signal is asserted in a first state, wherein said correction signal is used as said stored reset signal; and a detection circuit for monitoring a voltage level of said photo signal and asserting said control signal, said detection circuit asserting said control signal in said first state when said voltage level is less than a predetermined threshold, wherein said detection circuit comprises: a first circuit; an output node coupled to said control line; a bias transistor; and a switch transistor, wherein: said first circuit is coupled in series between a power supply and said output node, said output node is coupled to said bias transistor via a first source/drain of said bias transistor, said bias transistor is coupled to said switch transistor via a second source/drain of said bias transistor and a first source/drain of said switch transistor, and said switch transistor is coupled to said column line via a second source/drain of said switch transistor.