Maximum swing cascode circuit for a bipolar charge pump
US5066871A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 9, 1991 |
| Grant date | Nov 19, 1991 |
| Priority date | — |
| Expiry date | May 9, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/0422
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A maximum swing bipolar charge pump retains a cascode switching configuration for high breakdown. The charge pump includes a charge pump capacitor with a first plate connected to supply in the conventional manner. A first cascode-connected NPN transistor is utilized to switch the second plate of the pump capacitor to the supply. A second cascode-connected NPN transistor is utilized to switch the second plate of the pump capacitor close to ground. An additional bipolar biasing network holds the second NPN transistor out of heavy saturation when the second plate of the pump capacitor is switched close to ground, thereby preserving fast turn-off time and maximum voltage swing with the constraint of a bipolar cascode configuration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.