Operational amplification circuit, overheat detecting circuit and comparison circuit
US7034616B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 3, 2004 |
| Grant date | Apr 25, 2006 |
| Priority date | — |
| Expiry date | Apr 4, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2200/78
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
In a circuit according to the present invention, a multi-collector transistor is provided which includes first to third collectors so that, when a current does not flow from the second collector, a current from the first collector increases but a current from the third collector does not vary. When transistors of the circuit turn off because the voltage of an input signal gets out of an in-phase input voltage range, the supply of the current from the second collector comes to a stop and, hence, the current from the first collector increases. In this situation, further transistors carry out their on/off operations, thereby fixing the output of the circuit to a low level. That is, this circuit can, irrespective of poor pair compatibility between the transistors, fix the output logical level to a desired level when the voltage of an input signal gets out of an in-phase input voltage range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.