Title:
SWITCHING CAPACITOR CIRCUIT AND FLUCTUATION COMPENSATION OF ITS CIRCUIT CHARACTERISTIC
Document Type and Number:
Japanese Patent JPH03150926
Kind Code:
A
Abstract:
PURPOSE: To satisfy requests of low distortion and low noise by compensating the fluctuation of the electric capacity of a signal transmitting capacitor by the comparison with resistance in this circuit. CONSTITUTION: A switch capacitor circuit is composed of the signal capacitors 151 to 15N which have 1st resistance in a feedback path, and in which the 1st terminal selectively combines between a 2nd reference voltage 12 and an adding node 16 and the 2nd terminal selectively combines between a 2nd reference voltage 12 and the 1st reference voltage 11 corresponding to a signal transmission operational amplifier 18 combined with the adding node 16, the 1st reference voltage 11 and a digital input signal, 2nd resistance 30, and a switch capacitor 31. Then, a voltage difference between the 1st and the 2nd reference voltages 11 and 12 depends on the resistance value of the 2nd resistance 30 and the equivalent resistance of the switch capacitor 31, and the switch capacitor 31 compensates the fluctuation of the capacity of the signal capacitor by varying this voltage difference. Thus, requests of low distortion and low noise are satisfied.
Inventors:
JIEFURII UIRIAMU SUKOTSUTO
SAYAMUKURANGARA RAMASUWAMI BIS
SAYAMUKURANGARA RAMASUWAMI BIS
Application Number:
JP26398490A
Publication Date:
June 27, 1991
Filing Date:
October 03, 1990
Export Citation:
Assignee:
AMERICAN TELEPHONE & TELEGRAPH
International Classes:
H03M1/66; H03H19/00; H03M1/06; H03M1/74; H03M1/80; (IPC1-7): H03H19/00; H03M1/66; H03M1/74
Domestic Patent References:
| JPS6169217A | 1986-04-09 | |||
| JPS61236218A | 1986-10-21 | |||
| JPS6029023A | 1985-02-14 |
Attorney, Agent or Firm:
Hirofumi Mimata (1 person outside)