Process and apparatus for providing an analog waveform synchronized with an input signal
US5487027A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 18, 1994 |
| Grant date | Jan 23, 1996 |
| Priority date | — |
| Expiry date | May 18, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/18
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A waveform generator (20) for generating an analog wave which is synchronized with a signal from an input source (22). The waveform generator (20) includes a phase-locked loop (24) for receiving an input source signal and multiplying said signal by a multiplier. The multiplied square wave signal is then provided to a frequency divider (28) and to a first clock input (39) of a first switched-capacitor filter (29). The frequency divider (28) outputs a divided output signal that is received as an input to the phase-locked loop (25) and by the first switched-capacitor filter (35). As a result, the first switched-capacitor filter (29) outputs a first analog wave of a constant amplitude which is phase synchronized with the input source signal. This waveform generator (20) allows the 3 dB point of the filter to move as the input frequency changes. Further embodiments allow the addition of second switched-capacitor filter (50) and a shift register (45) for providing a second analog wave which is phase shifted from said input source signal yet is synchronized therewith.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.