| 摘要 |
PROBLEM TO BE SOLVED: To provide a control voltage generation circuit which, according to temperature change adjusts a control voltage for controlling a gain value, and a variable gain circuit using the control voltage generation circuit so as to avoid temperature dependency. SOLUTION: This invention comprises the control voltage generation circuit provided with a means for setting a current ratio of a drain current (or a collector current) of a first transistor constituting a differential circuit, to a drain current (or a collector current) of a second transistor constituting the differential circuit, and a means for outputting the voltage corresponding to the current ratio to between gate terminals (or base terminals) of the first and second transistors; and a differential amplifier stage of which gain value is controlled by the voltage output from the control voltage generation circuit. COPYRIGHT: (C)2005,JPO&NCIPI
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