PURPOSE: To increase the temperature control characteristics by forming the heat generating transistor into the fixing stand of the oscillator.

CONSTITUTION: Oscillator 1 is fixed on Si chip 21, and transistor 21a is incorporated into chip 21. The back electrode of the oscillator is insulated from chip 21. At the same time, electrode 22 of the oscillator, collector 24 of the transistor, base 25 and the electrode of emitter 26 are formed each. Oscillation IC28 is attached to substrate 27 along with transistor control IC29. The temperature detecting transistor is stored in package 3 to be connected to IC29. In this constitution, the occurrence of the temperature ripple is reduced with an extremely excellent rise characteristics since a thermal contact is secured between oscillator 1 and chip 21 incorporating heat generating transistor 21a. Furthermore, the heat generation power consumption can be reduced with a distinct of miniaturization, which can be applied suitably to the wristwatches.