Sound outputting devices using digital displacement data for a PWM sound signal
US5408583A · kind A · utility
5Cited by
2References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 14, 1992 |
| Grant date | Apr 18, 1995 |
| Priority date | — |
| Expiry date | Jul 14, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B14/026
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Sound information is binarized by delta modulation or adaptive delta modulation. The resulting data is subjected to pulse wide modulation and the resulting data is delivered to a reproducing device, which detects a leading edge of a received signal pulse to produce a self operation timing clock to thereby reproduce a sound. When the reproducing device detects the absence of edges for a predetermined interval after the edge detection, it turns off a power source for an analog circuit to suppress power consumption.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.