Direct-current stabilization power supply device
US6201674A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 12, 1999 |
| Grant date | Mar 13, 2001 |
| Priority date | — |
| Expiry date | Oct 12, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05F1/5735
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A current detection resistance such as a metal resistance is formed in series with a power transistor, and in response to an output voltage of the current detection resistance, an overcurrent protective circuit performs an overcurrent suppressing operation with high accuracy without being affected by irregularity of a current multiplication factor, etc.; thus, it is possible to realize a smaller chip area so as to reduce the cost. Furthermore, a short-circuit protective circuit returns a terminal voltage of a referenced resistance, that appears in accordance with a partial pressure value of an output voltage, at the transistor, a partial pressure resistance, and a current mirror circuit. And the short-circuit protective circuit controls a potential of a base resistance and suppresses a base current. Hence, it is not necessary to dispose the transistor for suppressing a current between base lines, so that a low-voltage operation can be realized. In a direct-current stabilization power supply device having a two-chip structure of a PNP power transistor and a control IC, it is possible to achieve a smaller chip area and a low-voltage operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.