Integrated circuit frequency controlled modulator for use in a phase lock loop
US5708383A · kind A · utility
Inventor
Key dates
| Filing date | Apr 26, 1996 |
| Grant date | Jan 13, 1998 |
| Priority date | — |
| Expiry date | Apr 26, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03D2200/0084
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A circuit for modulating an N-phase first waveform having a frequency F.sub.O with an N-phase second waveform having a frequency F.sub.M. The circuit includes N number of limited swing driver circuits. Each limited swing driver circuit has generator means for generating one phase of a third waveform in response to one phase of the first waveform so that the third waveform has a frequency F.sub.O and a voltage swing that is less than a voltage swing of the first waveform. The circuit also includes N number of multiplier circuits. Each multiplier circuit is coupled to one of the limited swing driver circuits and has multiply means for multiplying one phase of the third waveform with one phase of the second waveform and for generating first and second currents having a difference which is proportional to a product of the one phase of the third waveform and the one phase of the second waveform. A load circuit is coupled to the multiplier circuits and has a first node into which the first currents generated by each of the multiplier circuits are summed together to form a first summation current and a second node into which the second currents generated by each of the multiplier circuits…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.