Current limiting circuit
US4338646A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 27, 1981 |
| Grant date | Jul 6, 1982 |
| Priority date | — |
| Expiry date | Apr 27, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05F1/573
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A current limiting circuit is provided wherein the monitored voltage is applied to the base of first and second transistors, the first transistor having a substantially larger emitter area than the second transistor. Impedance means are connected to the emitters of the first and second transistors such that they function in conjunction with the emitter area ratio causing the current flowing through the first transistor to be higher than that flowing through the second transistor at low base voltages, while at higher base voltages the current flowing through the second transistor is higher than flowing through the first transistor. At some intermediate voltage the current flowing through both the first and second transistors is equal. This property may be used, for example, in a voltage regulator so as to divert base drive current from the output transistor at the point where the first and second currents are equal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.