Title:
VARIABLE GAIN AMPLIFICATION CIRCUIT
Document Type and Number:
Japanese Patent JP2014175763
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To provide a variable gain amplification circuit that has a flat gain over a wide band.SOLUTION: A variable resistor for gain setting is connected between source electrodes of first and second MOS transistors constituting a differential pair. A first variable capacitor is connected to the source electrode of the first MOS transistor, and a second variable capacitor is connected to the source electrode of the second MOS transistor. A third variable capacitor is connected to a drain electrode of the first MOS transistor, and a fourth variable capacitor is connected to a drain electrode of the second MOS transistor. Values of the first to fourth variable capacitors are controlled in accordance with a gain setting by the control of the variable resistor to match a pole frequency with a zero point frequency.
Inventors:
FUJII SHINSUKE
Application Number:
JP2013045251A
Publication Date:
September 22, 2014
Filing Date:
March 07, 2013
Export Citation:
Assignee:
TOSHIBA CORP
International Classes:
H03G3/10; H03G3/02
Domestic Patent References:
| JPS50110753A | 1975-09-01 | |||
| JP2009290682A | 2009-12-10 | |||
| JPS4922846A | 1974-02-28 | |||
| JPS5927612A | 1984-02-14 |
Attorney, Agent or Firm:
Hiroaki Sakai
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