Bridge circuit for driving an inductive load with a shoot-through prevention circuit
US5469095A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 27, 1994 |
| Grant date | Nov 21, 1995 |
| Priority date | — |
| Expiry date | Jun 27, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/664
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A bridge circuit, intended for use as a PWM driver of an inductive load, includes at least one source driver transistor connected in series totem-pole fashion with a sink driver transistor. A base resistor is connected from base to emitter of one of the driver transistors. This totem pole circuit is connected across a pair of DC supply conductors. A protective fly-back diode is connected across the one driver transistor. An auxiliary resistor is connected from the base of the auxiliary transistor to the emitter of the one driver transistor. When a fly-back diode across the one driver transistor conducts, the one driver transistor tends to conduct in the reverse direction and to store charge that in a subsequent period leads to shoot-through currents through the source and sink drivers. The auxiliary transistor turns on only when the fly-back diode conducts and shunts the base-collector of the source transistor, preventing its turning on and storing charge, and thus preventing potentially damaging shoot-through current through the driver transistors. The added auxiliary components do not cause additional power being drawn from the supply source, and therefore do not cause additional…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.