Pixel analog-to-digital converter using a ramped transfer gate clock
US7652706B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 15, 2006 |
| Grant date | Jan 26, 2010 |
| Priority date | — |
| Expiry date | Jul 25, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/78
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image sensor includes a photosensitive region that accumulates charge corresponding to received incident light; a transfer gate for transferring charge from the photosensitive region; a voltage supply having an increasing voltage over time; a floating diffusion for receiving the charge from the photosensitive region and converting the charge to a voltage; an amplifier for receiving and amplifying a signal from the floating diffusion; a comparator for comparing a voltage from the amplifier to a reference voltage; and a counter for counting clock cycles between initiation of the increasing voltage until a signal is received from the comparator indicating charge transfer from the photosensitive region to the floating diffusion; wherein a digital signal is generated that represents an unfilled capacity of the photosensitive region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.