Title:
OPERATIONAL AMPLIFIER CONVERTIBLE INTO DIFFERENT CONFIGURATIONS
Document Type and Number:
Japanese Patent JPH08139536
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To switch configuration into buffer constitution or high impedance output configuration and to prevent a system from being interfered by a transitional phenomenon at that time by using a small configuration element and a simple circuit on a circuit assembly provided with an operational amplifier having an input stage which is directly connected to an output stage taking the system of an AB class amplifier. SOLUTION: A compensation capacitor Cc is connected between the first input IN1 and the output OUT of the output stage 21 and regular feed back systems Rf1 and Rf2 are provided between the output OUT of the output stage and the input of the input stage 20. Three switch box S1, S2 and S3 can constitute the operational amplifier into three configurations. One is made to be the regular operational amplifier, one is made like a buffer and one is made to be that where an output terminal is in high impedance. In the AB class amplifier, final stage transistors Qpf and Qnf are continuously controlled.
Inventors:
EDOARUDO BOTSUTEI
TEITSUIAANA MANDORIINI
TEITSUIAANA MANDORIINI
Application Number:
JP20107995A
Publication Date:
May 31, 1996
Filing Date:
August 07, 1995
Export Citation:
Assignee:
SGS THOMSON MICROELECTRONICS
International Classes:
H03F3/68; H03F3/30; H03F3/45; H03F3/50; H03F3/72; (IPC1-7): H03F3/72; H03F3/50; H03F3/68
Attorney, Agent or Firm:
Takashi Ishida (3 others)