High efficiency quasi-square wave drive circuit for switching power amplifiers
US5276357A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 1, 1992 |
| Grant date | Jan 4, 1994 |
| Priority date | — |
| Expiry date | Sep 1, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K2217/0036
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A drive circuit generates a quasi-square wave for use in switching power amplifiers by supplying square wave signals which are 180.degree. out of phase, but otherwise identical, to the respective control inputs of two switching transistors. Opposite ends of the respective controlled paths of the transistors are connected to the input of the device which is being driven. The driven device input has a capacitance associated therewith, which normally results in a voltage loss as this capacitance is alternately charged and discharged. The circuit component values are selected so that this capacitance is charged while the switching transistors have yet to reach their threshold voltages, and thus at the moment when either transistor is switched to a conducting state the voltage across that transistors controlled path will be substantially zero, and the normal switching loss, which is a product of the square of that voltage, the input capacitance of the driven device, and the operating frequency, is eliminated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.