Low pass filters in DLL circuits
US6664830B2 · kind B2 · utility
16Cited by
3References
35Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Nov 30, 2001 |
| Grant date | Dec 16, 2003 |
| Priority date | — |
| Expiry date | Nov 30, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/093
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Circuits and methods are provided that reduce, if not prevent, the adverse effects of transient noise on phase adjustments made by digital delay lock loop (DLL) circuits, which typically generate a periodic output signal having a particular phase relationship with a periodic input signal. A digital low pass filter of a DLL circuit includes circuitry, such as, for example, a thermometer register, coupled to receive the outputs of a DLL phase detector. The low pass filter prevents the DLL circuit from making frequent changes to the phase of the DLL output signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.