Active pixel sensor with bootstrap amplification
US6211510A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 26, 2000 |
| Grant date | Apr 3, 2001 |
| Priority date | — |
| Expiry date | Jan 26, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10F39/803
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a first embodiment an active pixel sensor includes a photodiode for capturing photocharge, a reset transistor for resetting the photodiode to a reset potential, and a readout transistor, and in a second embodiment an active pixel sensor includes a photodiode for capturing photocharge, a reset transistor for resetting the photodiode to a reset potential, a transfer transistor for transferring captured photocharge, and a readout transistor. In both embodiments, the readout transistor has a drain that is coupled to a first supply voltage during integration of photocharge and a second supply voltage during readout of the photocharge. Accordingly, the sensitivity of an active pixel sensor is increased by increasing the fill factor, the noise an active pixel sensor is reduced by increasing the relative size of the readout transistor, and the gain is compressive as the relative light intensity in an active pixel sensor increases.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.