Title:
LOGARITHMIC AMPLIFIER
Document Type and Number:
Japanese Patent JP3536936
Kind Code:
B2
Abstract:
PURPOSE: To prevent the output abnormality when an excess input is caused to a logarithmic amplifier provided with a logarithm converting operational amplifier and a feedback circuit for feeding back an output from the operational amplifier through a resistor connected to the output terminal of the operational amplifier.
CONSTITUTION: An element (e.g. a series connection element consisting of Zener diodes 51, 52) in which equivalent resistance is reduced when voltage more than a prescribed value is impressed is connected in parallel with a resistor 30 connected to the output terminal 22c of the logarithm converting operational amplifier 22.
Inventors:
Yasuda, Hiroaki
Application Number:
JP21686094A
Publication Date:
June 14, 2004
Filing Date:
September 12, 1994
Export Citation:
Assignee:
FUJI PHOTO FILM CO LTD
International Classes:
G06G7/12; G06G7/24; H03G7/00; (IPC1-7): G06G7/24; G06G7/12