| 摘要 |
PROBLEM TO BE SOLVED: To provide a temperature compensation system which has simple circuit configuration and high temperature compensation accuracy and consequently reduces noise and is made low-cost and is suitable for a portable telephone or the like. SOLUTION: The temperature compensation system includes: a crystal oscillation circuit 12 provided with a crystal vibrator 11; a varactor diode 14 whose capacitance varies with a voltage across the varactor diode 14; high resistance resistors 16 to 22 for isolating each circuit; capacitors 1, 2, 4, 5; a temperature sensor section 101 for sensing ambient temperature; compensation voltage generating circuits 102, 103 for generating a temperature compensation voltage on the basis of a voltage of the temperature sensor section 101; and a reference voltage generating section 104 for applying a reference voltage of the compensation voltage generating circuits 102, 103 to them. COPYRIGHT: (C)2005,JPO&NCIPI
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