Feed-forward technique for power supply rejection ratio improvement of bit line
US9148596B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 2014 |
| Grant date | Sep 29, 2015 |
| Priority date | — |
| Expiry date | May 23, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/78
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image sensor read out circuit includes a first current mirror circuit in which a second current conducted through a second current path is controlled in response to a first current conducted through the first current path. The second current is conducted through an amplifier transistor of a pixel circuit. A first current source is coupled to the first current path to provide a substantially constant current component of the first current. A second current source is coupled to a power supply rail of the pixel circuit and coupled to the first current path to provide a ripple current component of the first current. The ripple current component provided by the second current source is responsive to a ripple in the power supply rail. The first current is responsive to a sum of the currents from the first and second current sources.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.