FREQUENCY CONVERSION MIXER

摘要

PURPOSE: A frequency conversion mixer is provided to reduce malfunction by maintaining a constant voltage between the DC voltage of first and second oscillation signals and the DC voltage of first and second input signals. CONSTITUTION: A biasing circuit includes a voltage follower(31), a current source(32,33), and a first diode(34). The voltage follower detects the DC voltage of a first input signal. The current source is connected to a DC power source. A first diode is connected between the output terminal and the current source of the voltage follower. The first diode obtains the DC voltage which is constantly higher than the voltage of the output terminal of the voltage follower. The first diode is formed with a P-channel field effect transistor. The source of the P-channel field effect transistor is connected to the output terminal of the voltage follower. The gate and drain of the P-channel field effect transistor are commonly connected to the current source.