Output driving circuit for use in DC stabilized power supply circuit
US5859757A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 26, 1997 |
| Grant date | Jan 12, 1999 |
| Priority date | — |
| Expiry date | Sep 26, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05F1/575
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An output transistor supplies a current based on a drive current to a load. An output voltage is divided by a feedback voltage, and an error amplifier outputs a voltage according to a difference in feedback voltage. Furthermore, the base drive circuit controls a drive current of the output transistor according to an output voltage of the error amplifier. The drive current flows into GND via only the drive current detecting resistor. The short-circuit overcurrent protecting circuit detects an overcurrent based on a terminal based voltage of the drive current detecting resistor, and detects an occurrence of a short circuit by observing a feedback voltage. According to the described arrangement, as the need of the short-circuit detection-use transistor to be biased by the drive current can be eliminated, variations in output voltage of the error amplifier can be suppressed, and improved transient response characteristics can be achieved. As a result, in a drive circuit for use in the DC stabilized power supply circuit provided with the short-circuit overcurrent protecting circuit, improved transient response characteristics can be achieved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.