Power supply circuit having a start up circuit
US6876180B2 · kind B2 · utility
6Cited by
9References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 11, 2002 |
| Grant date | Apr 5, 2005 |
| Priority date | — |
| Expiry date | Nov 11, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05F1/575
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A reference voltage circuit and an operational amplifier operate when an output voltage is produced from an output terminal of a power supply circuit. When the output voltage is low in the rising phase of a power source voltage, a transistor Q17 in a startup circuit turns on and a transistor Q14 turns off to surely turn on transistors Q11 and Q12. Upon the output voltage exceeding a predetermined level, the transistor Q17 turns off and an ordinary feedback control starts.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.