Analog bus driver and multiplexer
US8164663B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 16, 2006 |
| Grant date | Apr 24, 2012 |
| Priority date | — |
| Expiry date | May 28, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N25/78
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
For a source-follower signal chain, the ohmic drop in the selection switch causes unacceptable voltage offset, non-linearity, and reduced small signal gain. For an op amp signal chain, the required bias current and the output noise rises rapidly with increasing the array format due to a rapid increase in the effective capacitance caused by the Miller effect boosting up the contribution of the bus capacitance. A new switched source-follower signal chain circuit overcomes limitations of existing op-amp based or source follower based circuits used in column multiplexers and data readout. This will improve performance of CMOS imagers, and focal plane read-out integrated circuits for detectors of infrared or ultraviolet light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.