| 摘要 |
PROBLEM TO BE SOLVED: To provide a variable gain type differential amplifier and a multiplier using the same in which distortion can be reduced without changing an operating current. SOLUTION: Collectors of transistors 1, 2 are connected to a power supply terminal NVC for receiving a power supply voltage Vcc via resistors 3, 4. Emitters of the transistors 1, 2 are connected to ground terminals via resistors 5, 6. Between nodes N1, N2 connected to the emitters of the transistors 1, 2, a shunt resistor 7, an FET 9, and a shunt resistor 8 are serially connected. The gate of the FET 9 is connected to a control terminal NG for receiving a control voltage AGC via a resistor 10. The shunt resistors 7, 8, and the FET 9 constitute a variable resistor circuit 20. COPYRIGHT: (C)2005,JPO&NCIPI
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