Headphone driver/charge pump combination
US8476978B2 · kind B2 · utility
0Cited by
30References
13Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 8, 2008 |
| Grant date | Jul 2, 2013 |
| Priority date | — |
| Expiry date | Jun 20, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R3/007
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A headphone driver amplifier operative without an external negative voltage power supply, coupled directly to the headphone speakers without the need for DC coupling capacitors used for preventing DC reaching the headphones. An onboard power supply generates a negative voltage rail which powers the output amplifiers, allowing driver amplifier operation from both positive and negative rails. Since the amplifiers can be biased at ground potential (O volts), no significant DC voltage exists across the speaker load and the need for DC coupling capacitors is eliminated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.