PURPOSE: To adjust temperature characteristics quickly by providing the first ∼ third temperature sensitive resistors in the front stage of a temperature compensating circuit, and providing a temperature compensating circuit that applies voltage generated between terminals of the third temperature sensitive resistor to a voltage capacity converting element connected to a crystal oscillator.
CONSTITUTION: Temperature sensitive resistors RMT and RLT are cascade connected between supply terminals (a), (b) of voltage Vi, and a resistance R and a temperature sensitive resistor RHT are cascade connected between terminals of the RLT, and voltage between terminals of the RHT is made compensating voltage V0 applied between terminals of a variable capacity diode 3. By selecting the value of resistance R of a temperature compensating circuit 6, limit value in high temperature side of compensating voltage V0 can be shifted to low temperature side. Accordingly, voltage characteristics to temperature of the temperature compensating circuit can be made three-dimensional curve within a prescribed temperature range, and temperature voltage characteristic in high temperature side can be designed freely.
NARITA YOSHINORI
YAMASHITA KIYOSHI
