Amplifier incorporating current-limiting protection of output transistor
US5384549A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 30, 1993 |
| Grant date | Jan 24, 1995 |
| Priority date | — |
| Expiry date | Nov 30, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F1/52
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An amplifier circuit having a stabilized power supply circuit as a power source is arranged to ensure that, when the output is short-circuited to a power supply line, the amplifier circuit and the stabilized power supply circuit are protected, the output from the stabilized power supply circuit is stably maintained and the short-circuit failure can be distinguished from use of the amplifier circuit. A first transistor forming a common-emitter circuit constitutes an output section of the amplifier circuit. A second transistor having the same polarity as that of the first transistor has its collector and base connected to each other and to the base of the first transistor. The emitters of the first and second transistors are connected to each other. The emitter of a third transistor forming an emitter-follower circuit is connected to the point of connection between the collector and the base of the second transistor. A current limiter circuit is connected to the collector of the third transistor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.