Document Type and Number:
Japanese Patent JPH0429247
Kind Code:
B2
Abstract:
PURPOSE:To reduce the number of power supply terminals and to facilitate making a switched capacitor integrator into an integrated circuit, by using the power source of an operational amplifier for the discharge path of a switched capacitor circuit and the bias circuit for the operational amplifier. CONSTITUTION:An input voltage Vi is applied to a contact a1 of a switch S1 of a switched capacitor circuit 60, and a contact b1 is connected to a power source voltage VDD' and a contact a2 of a switch S2 is connected to an inverted input terminal - of an operational amplifier 31, and a contact b2 is connected to a power source voltage VSS. Voltages VDD and VSS are supplied to the operational amplifier 31, and the output terminal is connected to the inverted input terminal - through a capacitor Cf, and the middle voltage between voltages between voltages Vdd and VSS is applied to the noninverted input terminal +. Thus, when switches S1 and S2 are connected to contacts a1 and b2, a potential difference Vi-VSS is applied to a switched capaitor CS. When switches S1 and S2 are connected to contacts b1 and a2, a potential difference VDD-V'i is applied to the switch capacitor CS, and the circuit 60 functions as a negative resistance.
Application Number:
JP13723781A
Publication Date:
May 18, 1992
Filing Date:
September 01, 1981
Export Citation:
International Classes:
G06G7/186; G10L15/02; H03H19/00
Next Patent: JPH0429248