| 摘要 |
A multiplier having a simple constitution, excellent performance with respect to high-frequency characteristics and distortion characteristics, and allows low-voltage operation. Transistor Q 11 , resistors R 11 and R 12 form a common-emitter circuit. One signal of differential signal v 1 is amplified by the common-emitter circuit, and the amplified signal is input to an emitter follower composed of transistor Q 12 . The output current of the emitter follower is input through resistor R 13 into the current mirror circuit composed of transistors Q 13 and Q 14 . Output current I 5 of said current mirror circuit is input to the transistor pair of transistor Q 19 and npn transistor Q 20 . By selecting an appropriate gain for the common-emitter circuit, currents I 5 and I 6 generated in this way become independent of the base-emitter voltage, and performance is improved with respect to distortion characteristics.
|
