Phase-switched dual-mode counter circuit for a frequency synthesizer
US7116747B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 27, 2002 |
| Grant date | Oct 3, 2006 |
| Priority date | — |
| Expiry date | Nov 18, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/1974
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A dual-modulus prescaler circuit for a frequency synthesizer comprises a plurality of asynchronous dividers-by-two connected in series, a phase selector unit (11) between two dividers-by-two (10, 12) and a control unit (13) for supplying control signals (S0, S1, S2) to the selector unit as a function of a selected mode. Said selector unit receives four signals phase shifted by 90° in relation to each other from a master-slave first divider and supplies a selected one of the four phase shifted signals. The control signals (S0, S1, S2) are supplied to the selector unit for selecting one of the four phase shifted signals (F2) at the output in a particular division period. As a function of the control signals supplied by the control unit (13) in one selected of the modes, the selector unit effects phase switching in each division period between two phase shifted signals selected by each branch. The second phase shifted signal i in phase lead of 90° in relation to the first phase shifted signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.