Patent · US Expired

Semiconductor integrated circuit having function for switching operational mode of internal circuit

US4771407A · kind A · utility

21Cited by
1References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 29, 1987
Grant dateSep 13, 1988
Priority date
Expiry dateJul 29, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C29/46
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

In a semiconductor integrated circuit having first and second power supply lines for receiving a power supply voltage, an external input terminal for receiving an input signal, and a high voltage detection circuit for detecting at the external input terminal a high voltage higher than a predetermined voltage which is higher than the power supply voltage, the high voltage detection circuit comprises an input circuit connected to the external input terminal for generating circuit for generating a reference voltage; and a differential voltage amplifier connected to receive the detection voltage and the reference voltage for amplifying the difference between the detection voltage and the reference voltage, to thereby determine whether the high voltage is applied, the input circuit comprising; a level shift element connected to the external input terminal for providing the detection voltage; an impedance element connected between the level shift element and the second power supply line; and a leak current compensating element connected between the first power supply line and the level shift element for allowing a current to flow from the first power supply line through the leak current …

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