Apparatus for a low voltage differential amplifier incorporating switched capacitors
US5565813A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 15, 1995 |
| Grant date | Oct 15, 1996 |
| Priority date | — |
| Expiry date | May 15, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/45201
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A low voltage differential amplifier 10 or comparator is accomplished by providing an differential amplifier 10 that includes a transistor bias simulator 32 and a capacitance circuit 36. The transistor bias simulator 32 matches the gate to source bias voltage of the load transistor 22 and provides this value to the capacitance circuit 36. The capacitance circuit 36, which is coupled to a biasing reference voltage 38, charges a capacitor 84 based on the difference between the biasing reference voltage 38 and the simulated bias voltage 34. This charged capacitor 86 is used during an auto-zeroing phase to bias the drain to source voltage of the load transistor 22 to a state at which it is just beyond the onset of saturation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.