Patent · US Expired

Circuit for the generation of a scanning clock in an operational anaylsis device of the serial type for an integrated circuit

US5220217A · kind A · utility

10Cited by
5References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 18, 1991
Grant dateJun 15, 1993
Priority date
Expiry dateDec 18, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K5/135
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The circuit comprises a first switching circuit which receives at an input a system clock normally provided for the operation of the integrated circuit and produces at an output a machine clock normally coincident with the system clock, circuitry for clamping the first switching circuit responsive to a firing signal of the serial operational analysis device determines which state the machine clock is clamped in and second switching circuit which receives at an input the system clock and is responsive to the firing signal to produce a scanning clock which repeats the system clock in an inverted or non-inverted manner according to the state in which the machine clock has been clamped.

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