PURPOSE: To suppress the temperature change of the parasitic capacity of an amplifying part in which it is difficult to improve the temperature change of an oscillation frequency only by considering the temperature characteristic of a high frequency LC type oscillation circuit constituting oscillation, and to generate the constant oscillation frequency, in a temperature compensating circuit which operates temperature compensation at the time of amplifying a signal from the LC type oscillation circuit.
CONSTITUTION: A high frequency signal from the LC oscillation circuit is inputted to an input terminal, and a bias voltage obtained by dividing a power supply voltage into a resistance Rt and a negative characteristic element Rt1 (or a positive characteristic element Rt and a resistor Rt') is supplied to the input terminal, so that the parasitic capacity of the amplifying part can be temperature-compensated. Then, the amplified high frequency signal is outputted.
IZUMI KIYOHIKO
SATO MITSURU
