Dual-drive coupling for output amplifier stage
US6388523B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 16, 2000 |
| Grant date | May 14, 2002 |
| Priority date | — |
| Expiry date | Oct 16, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F3/3023
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A dual-drive coupling for an output stage of class AB amplifier is disclosed. A class AB amplifier comprises a PMOS output device and an NMOS output device coupled together. Two signal sources are used; one to drive the PMOS output device and one to drive the NMOS output device. The signal source driving the PMOS output device has a transconductance that is three times greater than the signal source driving the NMOS output device because the PMOS device is about three times bigger than the NMOS output device. A floating resistor network, comprised of an NMOS transistor and a PMOS transistor is coupled between the coupling of the signal sources with the output devices. A replica device can be added between the PMOS output device and its corresponding signal source to replicate the drain voltage of the signal source for the NMOS output device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.