公开(公告)号：EP2104234B1

公开(公告)日：2011-08-31

申请号：EP08153179.0

申请日：2008-03-21

Applicant: STMicroelectronics Limited

Inventor： Purcell, Matthew ,  Storm, Graeme ,  Qu, Min

IPC: H03M1/08 ,  H04N5/335

CPC classification number: H04N5/3355 ,  H04N5/3575 ,  H04N5/3577 ,  H04N5/378

Abstract: An image sensor has a per-column ADC arrangement including first and second capacitors for correlated double sampling, and a comparator circuit. The capacitors are continuously connected to, respectively, the analog pixel signal and a ramp signal without use of a hold operation. The comparator circuit comprises a differential amplifier having one input connected to the junction of the two capacitors and another input connected to a reference signal. The reference signal is preferably sampled and held from a reference voltage. The use of a differential amplifier as first stage of the comparator addresses problems arising from ground voltage bounce when a large pixel array images a scene with low contrast.

公开(公告)号：EP2104234A1

公开(公告)日：2009-09-23

申请号：EP08153179.0

申请日：2008-03-21

Applicant: STMicroelectronics Limited

Inventor： Purcell, Matthew ,  Storm, Graeme ,  Qu, Min

IPC: H03M1/08 ,  H04N5/335

CPC classification number: H04N5/3355 ,  H04N5/3575 ,  H04N5/3577 ,  H04N5/378

Abstract: An image sensor has a per-column ADC arrangement including first and second capacitors for correlated double sampling, and a comparator circuit. The capacitors are continuously connected to, respectively, the analog pixel signal and a ramp signal without use of a hold operation. The comparator circuit comprises a differential amplifier having one input connected to the junction of the two capacitors and another input connected to a reference signal. The reference signal is preferably sampled and held from a reference voltage. The use of a differential amplifier as first stage of the comparator addresses problems arising from ground voltage bounce when a large pixel array images a scene with low contrast.

Abstract translation: 图像传感器具有包括用于相关双重采样的第一和第二电容器以及比较器电路的每列ADC装置。 电容器分别连续地连接到模拟像素信号和斜坡信号，而不使用保持操作。 比较器电路包括差分放大器，其具有连接到两个电容器的结的一个输入端和连接到参考信号的另一输入端。 参考信号优选地从参考电压采样和保持。 使用差分放大器作为比较器的第一级可以解决当大像素阵列以低对比度成像场景时，由接地电压反弹引起的问题。