Scheme of boosting adjustable ground level(s) of storage capacitor(s) of bjt pixel circuit(s) in pixel array circuit of image sensor apparatus

Abstract

A bipolar junction transistor (BJT) pixel circuit, including: a BJT transistor, having a base coupled to a photo detector, an emitter coupled to a shutter circuit, and a collector coupled to a reference ground level; the photo detector, having first end coupled to the base of BJT transistor and second end coupled to the reference ground level, for generating base current based on light intensity of light incident on the photo detector; the shutter circuit, coupled to the emitter of the BJT transistor, for controlling exposure time of the photo detector according to a shutter signal; and a storage capacitor, coupled between the shutter circuit and an adjustable ground level different from the reference ground level, for storing image data captured by the photo detector, wherein the adjustable ground level is boosted to be higher than the reference ground level for one or more times during the exposure time.