Class AB amplifier with improved phase margin
US5412344A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 19, 1993 |
| Grant date | May 2, 1995 |
| Priority date | — |
| Expiry date | Nov 19, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F1/086
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An amplifier circuit providing high power efficiency and an improved phase margin includes a transconductance input stage, one output of which is connected to an input of a class AB amplifier gain stage to form a compensation node, and the other output of which drives a current gain means, with the outputs of the current gain means and the class AB amplifier forming a current summing output node that is coupled to the compensation node through a compensation capacitor. The phase margin of the amplifier circuit is optimized by selecting the gain of the current gain means to be approximately equal to one plus the ratio of the capacitance of the load to the capacitance of the compensation capacitor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.