Apparatus and method for control supply output voltage techniques to track battery voltage
US7570039B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 4, 2005 |
| Grant date | Aug 4, 2009 |
| Priority date | — |
| Expiry date | Aug 4, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J7/0068
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A voltage regulation and battery charging system is provided. The system can simultaneously provide a regulated output voltage and charge a battery. The system includes a battery charger circuit, a voltage regulator circuit, and a voltage tracking circuit. A voltage divider is used to provide the voltage regulator circuit with a feedback voltage from the output voltage. Further, the voltage tracking circuit is operable to draw current from the voltage divider such that the regulated output voltage tracks the battery voltage if the battery voltage is above a threshold voltage. The voltage tracking circuit includes an op amp, a current mirror, and a resistor that is coupled between the inverting input of the op amp and the battery. The noninverting input of the op amp receives the threshold voltage. Additionally, the output of the op amp is coupled to the gates of the transistors in the current mirror.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.