Circuit for sensing load current of a voltage regulator
US8648586B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 2011 |
| Grant date | Feb 11, 2014 |
| Priority date | — |
| Expiry date | Feb 11, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05F3/26
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A circuit for sensing load current of a voltage regulator. The circuit includes a power transistor and a mirror transistor. A first transistor sizing circuit is coupled to the power transistor and is operable to control size of the power transistor based on a bias voltage of the power transistor, thereby regulating a first voltage for varying load conditions. The circuit also includes a feedback amplifier coupled to the power transistor and the mirror transistor. A transistor is coupled to the feedback amplifier and the mirror transistor. An analog to digital converter (ADC) is coupled to the transistor. A second transistor sizing circuit is coupled to the mirror transistor, the transistor, and the ADC. The second transistor sizing circuit is responsive to an output voltage to control size of the mirror transistor, thereby ensuring that accuracy of output voltage sensed by ADC is not limited by ADC's resolution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.