Digital integrated circuit propagation delay time controller
US4641048A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 24, 1984 |
| Grant date | Feb 3, 1987 |
| Priority date | — |
| Expiry date | Aug 24, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K2005/00228
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A propagation delay time controller comprises a phase locked ring oscillator and a bias signal generator for controlling the propagation delay time of logic elements on an integrated circuit. The logic elements are of a type in which propagation delay time is a function of an applied bias signal. The ring oscillator, comprising representative logic elements on the controlled integrated circuit, oscillates with a frequency dependent on the propagation delay time of the oscillator logic elements. The bias signal generator compares the oscillator output voltage with a known, pulsed reference signal and generates a bias signal proportional to the integral of the phase difference between the oscillator and reference signal pulses. The bias signal is applied to all logic elements in the ring oscillator and to all other logic elements on the integrated circuit to be controlled. The bias signal thus holds propagation delay time in each controlled logic element to a value fixed by the frequency of the reference signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.