Electronic switching circuit
US5493487A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 6, 1993 |
| Grant date | Feb 20, 1996 |
| Priority date | — |
| Expiry date | Dec 6, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M3/1555
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A pulse-width modulated (PWM) circuit provides current through a load by opening and closing main electronic switches which connect the load to a power supply. Each main electronic switch connects with an auxiliary switch, connected in series with a diode, the auxiliary switch and diode being called "recovery paths". The recovery paths provide a path between the load and the associated main switch, on one side, and the power supply on the other. A first train of pulses, derived from a command signal, drives the main switches, and a second train of pulses, derived from the first pulse train, controls the switches in the recovery paths. One arranges the second train such that the recovery paths carry current only while the main switches change from on to off, or from off to on. In this way, the recovery paths carry part of the current that would otherwise flow transiently through the main switches, due to the inherent inefficiencies in semiconductor switching. Therefore, the present invention allows the main switches to increase in efficiency as compared with circuits of the prior art. In an alternative embodiment, the recovery path includes the load but excludes the power supply, so…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.