Title:
LOW-DISTORSION AMPLIFIER OUTPUT STAGE FOR ANALOG/DIGITAL CONVERTER
Document Type and Number:
Japanese Patent JPH0583042
Kind Code:
A
Abstract:
PURPOSE: To obtain a low-distortion output part for a digital-to-analog converter(DAC) which uses a switched capacitor filter for an analog part. CONSTITUTION: The output stage of the DAC is used in combination with the switched capacitor filter to drive a low-impedance load. A 1st current source is composed of a transistor(TR) 284 and supplies a current to a load resistance 264 at the time of positive output voltage variation. A 2nd current source is composed of a TR 286 and sinks a current from the load resistance when voltage variation is small. The TR 284 performs class-AB operation. When the gate voltage of the TR 284 rises, the current flowing to the TR decreases and the current flowing to TRs 286 and 292 in mirror image relation with a TR 288 increases to sink the load current. The TRs 284 and 286 supply a load current irrelevant to the drain current of a TR 266 to the load resistance.
Inventors:
JIEFURII UIRIAMU SUKOTSUTO
Application Number:
JP2577892A
Publication Date:
April 02, 1993
Filing Date:
January 16, 1992
Export Citation:
Assignee:
CRYSTAL SEMICONDUCTOR CORP
International Classes:
H03F1/32; H03F3/30; H03F3/343; H03H11/12; H03H19/00; H03M1/08; H03M1/66; H03M3/02; (IPC1-7): H03F1/32; H03F3/343; H03H11/12; H03H19/00; H03M1/08; H03M1/66; H03M3/02
Domestic Patent References:
| JP62085015B |
Attorney, Agent or Firm:
Koichiro Kato (2 outside)
Next Patent: HIGH FREQUENCY AMPLIFIER