Title:
CONSTANT-VOLTAGE GENERATING CIRCUIT
Document Type and Number:
Japanese Patent JPS6249422
Kind Code:
A
Abstract:
PURPOSE:To obtain the titled circuit which is strong against a temperature variation and whose power consumption is small, and also to use it in a circuit in which a supply power source voltage is low, by boosting the supplying power source voltage by a switched capacitor circuit and generating a reference voltage which is higher than the supply power source voltage,and using a constant-voltage diode having a Zener voltage which is higher than the supply power source voltage. CONSTITUTION:When the potential of an output terminal 8 and the potential of a connecting point 7 of a switched capacitor circuit 1 become higher than a threshold voltage of a MOSFET 15, the MOSFET 15 exerts no influence on the potential of the output terminal 8. On the other hand, when the sum of a Zener potential Vz of a constant-voltage diode 2 and a threshold voltage Vtn of a MOSFET 3 coincides with the potential of the output terminal 8,the potential of the output terminal 8 is maintained in (Vz+Vtn) and goes to a reference voltage, and the reference voltage of (Vz+Vtn) is divided into object voltages by MOSFETs 41-43 of a load circuit 4. A MOSFET 44 becomes an off-state, when no current is flowing to the constant- voltage diode 2, and when the switched capacitor circuit 1 is not executing a switching operation, it is prevented that an unnecessary current flows.
Inventors:
SHIBATA YASUO
Application Number:
JP19068785A
Publication Date:
March 04, 1987
Filing Date:
August 28, 1985
Export Citation:
Assignee:
NEC CORP
International Classes:
G05F3/24; H03H19/00; (IPC1-7): G05F3/24; H03H19/00
Attorney, Agent or Firm:
Uchihara Shin