Comparator, analog-to-digital convertor, solid-state imaging device, camera system, and electronic apparatus
US8749424B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 31, 2013 |
| Grant date | Jun 10, 2014 |
| Priority date | — |
| Expiry date | Jan 31, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/123
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A comparator includes a first amplifier, a second amplifier, and a level holding part. The first amplifier includes differential-pair transistors and outputs a signal of a level corresponding to a comparison result from a first output node. The differential-pair transistors compare a reference voltage with a potential of an input signal. The second amplifier gain up the signal output from the first output node of the first amplifier and outputs the signal from a second output node. The level holding part holds a level of the second output node at a predetermined level. The second amplifier includes a transistor for amplification and a transistor for a current source. The level holding part holds the level of the second output node of the second amplifier such that the transistor for the current source does not fall into a level at which a saturated operation condition is not satisfied.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.