Patent ID: 7382204
Filing Date: 2008-06-03
Classification: H03B,H03L

Abstract:
1. A constant temperature crystal oscillator, comprising on a circuit substrate: a surface-mount crystal resonator which is provided with two crystal terminals as mount terminals and a first dummy terminal on a bottom surface, and has a metal cover; an oscillation circuit element which forms an oscillation circuit together with the crystal resonator; and a temperature control element which keeps a constant operation temperature of the crystal resonator, in which the temperature control element comprises at least a heating chip resistor, a power transistor for supplying electric power to the chip resistor, and a temperature sensitive resistor for detecting the operation temperature of the crystal resonator, wherein a second dummy terminal on a substrate side of the circuit substrate for connection to the first dummy terminal of the crystal resonator is connected to a resistor terminal on the substrate side to which the temperature sensitive resistor is connected through a thermally conductive path.