Patent ID: 9412784
Filing Date: 2016-08-09
CPC Classification: G06F,H01L

Claim Text:
1. A pre-flash time adjusting circuit which comprises a first pre-flash time adjusting unit coupled to an image sensing array, wherein the image sensing array comprises a plurality of pixel units, and the first pre-flash time adjusting unit comprises: a switching module, wherein a first switch of the switching module is coupled to a first pixel group of the image sensing array, and a second switch of the switching module is coupled to a voltage source, wherein the first pixel group comprises a plurality of first pixel units of the pixel units; and a storage capacitor, wherein a first end of the storage capacitor is coupled to the switching module, and a second end of the storage capacitor is coupled to a ground; wherein when the image sensing array senses a light beam, the switching module selectively connects the first switch and the storage capacitor, such that the storage capacitor starts to charge the first pixel units of the first pixel group, until base-emitter voltages of a plurality of bipolar junction transistors disposed in the first pixel units reaches a stable state.