Method and apparatus for improving the performance of digital delay locked loop circuits
US6069506A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 20, 1998 |
| Grant date | May 30, 2000 |
| Priority date | — |
| Expiry date | May 20, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/0816
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for improving the performance and accuracy of a digital delay locked loop (DDLL) by using a unique correction latch and novel reset mechanism circuit for eliminating DDLL minimum and maximum delay states of inoperability. The accuracy of a DDLL is further improved by the use of a three-NAND gate logic delay element design. A DDLL according to the present invention provides symmetrical rising and falling edges of the signal at the output of each delay line element. A DDLL according to the present invention further ensures insensitivity to random values upon initialization. In addition, a DDLL according to the present invention has increased accuracy due to ensuring a comparison between the actual, not divided-down, input signal and an output signal during a phase detect operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.