Digital method to eliminate power-on pops and clicks
US5796851A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 5, 1996 |
| Grant date | Aug 18, 1998 |
| Priority date | — |
| Expiry date | Dec 5, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/66
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A personal computer audio system is presented with a mechanism for digitally regulating the rate of voltage change of an audio output signal In one embodiment, the audio output signal from an integrated circuit is provided by means of a two-state audio amplifier. The first state of the amplifier is a high impedance state which exists prior to power-on and is maintained until an enable signal is asserted. When the enable signal is asserted, the amplifier drives the audio output signal line. Prior to the transition from the first to second states, a D/A converter is used to provide a ramp signal from the minimum voltage to the nominal operating voltage. The state transition is then initiated during the initial portion of the ramp signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.