Abstract: A readout circuit for an image sensor having a pixel array with at least one pixel group, in particular pixel column, with a plurality of pixels connected to a group bus comprises a group input for connecting to the group bus and a signal output for connecting to an input of an ADC. The readout circuit further comprises a first and a second reference terminal for receiving a first and a second reference voltage. A sampling bank comprises at least two sample-and-hold elements connected in parallel between the group input and an output of the sampling bank and further comprises a bypass switch connected in parallel to the sample-and-hold elements. A charge store is connected between the output of the sampling bank and the signal output. A first charge switch is connected between the first reference terminal and the signal output, and a second charge switch is connected between the second reference terminal and the output of the sampling bank.

Abstract: An analog-to-digital converter for an image sensor comprises a counter circuit to generate a respective counter bit in response to a counter state of the counter circuit, and a storage circuit for storing a respective storage state in response the respective counter bit. The converter further comprises a comparator circuit for generating a level of a comparison signal, and a synchronization circuit to generate a write control signal for controlling the storing of the respective storage state in the respective storage cell. The counter circuit is configured to change the counter state, when a first edge of a cycle of the clock signal is applied to the counter circuit, and to generate the write control signal, when a second edge of the cycle of the clock signal being subsequent to the first edge of the cycle of the clock signal is applied to the synchronization circuit.

Abstract: A readout circuit for an image sensor having a pixel array with at least one pixel group, in particular pixel column, with a pluralityof pixels connected to a group bus comprises a group input for connecting to the group bus and a signal output for connecting to an input of an ADC. The readout circuit further comprises a first and a second reference terminal for receiving a first and a second reference voltage. A sampling bank comprises at least two sample-and-hold elements connected in parallel between the group input and an output of the sampling bank and further comprises a bypass switch connected in parallel to the sample-and-hold elements. A charge store is connected between the output of the sampling bank and the signal output. A first charge switch is connected between the first reference terminal and the signal output, and a second charge switch is connected between the second reference terminal and the output of the sampling bank.

Abstract: An analog-to-digital converter for an image sensor comprises a counter circuit to generate a respective counter bit in response to a counter state of the counter circuit, and a storage circuit for storing a respective storage state in response the respective counter bit. The converter further comprises a comparator circuit for generating a level of a comparison signal, and a synchronization circuit to generate a write control signal for controlling the storing of the respective storage state in the respective storage cell. The counter circuit is configured to change the counter state, when a first edge of a cycle of the clock signal is applied to the counter circuit, and to generate the write control signal, when a second edge of the cycle of the clock signal being subsequent to the first edge of the cycle of the clock signal is applied to the synchronization circuit.