Title:
CONSTANT-VOLTAGE CIRCUIT
Document Type and Number:
Japanese Patent JPS5858618
Kind Code:
A
Abstract:
PURPOSE:To exactly perform a power-down function, by adding two MOS transistors (TR) whose polarity is different, to a conventional constant-voltage circuit, and also constituting the conventional constant-voltage circuit when power-down is not performed, by said addition. CONSTITUTION:When generating a power-down output, a power-down signal is applied to a terminal 19 in order that an MOS TR 17 is turned on, and a MOS TR 18 is turned off. As a result, the TR 17 is turned on, and the TR 18 is turned off. As a result, the gates of TRs 4 and 5 are connected, also the TRs 4 and 5 are connected in series, the gate and the drain of the TRs 4 and 5 become an open state which is not short-circuited, and its circuit configuration is constituted of a CMOS invertor. In this case, as a result of the fact that the TR 17 has been turned on, the TR 5 also conducts, an output terminal 3 becomes nearly ground potential 2, the potential of the output terminal 3 becomes nearly ground potential, a TR 10 is turned off, and the power is cut off.
Inventors:
SATOU HIDEHIRO
Application Number:
JP15482181A
Publication Date:
April 07, 1983
Filing Date:
October 01, 1981
Export Citation:
Assignee:
HITACHI LTD
International Classes:
G05F3/24; (IPC1-7): G05F1/56
Attorney, Agent or Firm:
Masami Akimoto