Patent · US Expired

Data processing system and method of operation having input/output drivers with reduced power consumption and noise levels

US5974259A · kind A · utility

6Cited by
21References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 18, 1996
Grant dateOct 26, 1999
Priority date
Expiry dateSep 18, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02D10/00
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A data processing system has a memory bus and a system input/output (I/O) bus including I/O drivers. The memory and I/O buses are controlled by a central processor unit (CPU) for transferring data therebetween and to the I/O drivers. A central clock provides clock signals to the CPU, the memory bus and the I/O bus. The central clock further provides memory and I/O phase alignment signals to the CPU, the alignment signals indicating to the CPU when the start of the CPU clock cycle coincides with the start of a memory bus clock cycle or I/O bus clock signal. Circuit means responsive to the phase alignment and CPU clock signals initiate the transfer of data to the memory and I/O data buses in alternate CPU clock signals to reduce the number of I/O pin switching at any given time thereby reducing the noise and power consumption at the I/O pins and in the system.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.