Title:
REVERSE CURRENT PREVENTING CIRCUIT
Document Type and Number:
Japanese Patent JPH04261332
Kind Code:
A
Abstract:
PURPOSE: To prevent lighting of an LED for an operational panel with small number of components by preventing a current from a host apparatus by means of a diode in an integrated circuit.
CONSTITUTION: If a power source of a printer is turned OFF, VCC=0[V], and a current is supplied from a voltage source 1 of a host apparatus through a pull-up resistor 3. A current supply route to loads in the printer connected to the source VCC 9 of a MOSIC can be eliminated by a unidirectional current blocking diode 8. Thus, a current supply route to an LED 12, etc., for an operational panel is not formed thereby to prevent firing, etc., of the LED 12.
Inventors:
OKADA TAKEYUKI
Application Number:
JP4111191A
Publication Date:
September 17, 1992
Filing Date:
February 13, 1991
Export Citation:
Assignee:
NEC CORP
International Classes:
H02H11/00; H02J1/00; (IPC1-7): H02H11/00; H02J1/00
Attorney, Agent or Firm:
Nobu Yanagikawa