Programmable current source for a time of flight 3D image sensor
US9658336B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 20, 2014 |
| Grant date | May 23, 2017 |
| Priority date | — |
| Expiry date | Dec 25, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S17/894
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A programmable current source for use with a time of flight pixel cell includes a first transistor. A current through the first transistor is responsive to a gate-source voltage of the first transistor. A current control circuit is coupled to the first transistor and coupled to a reference current source to selectively couple a reference current of the reference current source through the first transistor during a sample operation. A sample and hold circuit is coupled to the first transistor to sample a gate-source voltage of the first transistor during the sample operation. The sample and hold circuit is coupled to hold the gate-source voltage during a hold operation after the sample operation substantially equal to the gate-source voltage during the sample operation. A hold current through the first transistor during the hold operation is substantially equal to the reference current.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.