Title:
VARIABLE GAIN AMPLIFIER DEVICE AND METHOD FOR MEASURING ITS GAIN
Document Type and Number:
Japanese Patent JP3468197
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To stably and highly accurately calculate the gain of a variable gain amplifier device used to fetch an analog signal of servo control or the like.
SOLUTION: This variable gain amplifier device is newly provided with an input 9 for measurement. As a first step, the switch S2 of a switch group 6 is turned on, switches S1 and S3 to S5 are individually turned off and the gain G1 of a variable attenuator 3 seen from the input 1 is calculated. As a second step, the switch S4 is turned on, the switches S1 to S3 and S5 are individually turned off and the gain G2 of the attenuator 3 seen from the terminal 9 for measurement is calculated. As a third step, the gain of the attenuator 3 when the switch S4 is turned on and the switches S1 to S3 and S5 are individually turned off is calculated by adding the gains G1 and G2.
Inventors:
Koji Kanai
Application Number:
JP2000059962A
Publication Date:
November 17, 2003
Filing Date:
March 06, 2000
Export Citation:
Assignee:
Matsushita Electric Industrial Co., Ltd
International Classes:
G01R31/00; H03G3/00; H03G3/10; H03H7/24; (IPC1-7): H03G3/10; G01R31/00; H03G3/00; H03H7/24
Domestic Patent References:
| JP61242407A | ||||
| JP11298272A | ||||
| JP7326970A | ||||
| JP7212231A |
Attorney, Agent or Firm:
Fumio Iwahashi (2 others)
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