Start device for crystal oscillator

Abstract

Abstract PURPOSE:To quicken the start of a crystal oscillator, by constituting so that the battery voltage is intermittently applied at starting only, in a crystal oscillator using a constant voltage power supply lower than the battery voltage as the power supply. CONSTITUTION:An electronic timepiece is constituted with the 1st and 2nd frequency dividers 5, 6 frequency-dividing an oscillated output of a crystal oscillator 4, and a driving circuit 7 driving a display section 8. A CR oscillation circuit 2 is provided across a power supply 1 and a switching circuit 16 is provided among the oscillator 4, a constant voltage circuit 9 and ground (potential Vss). An oscillation detecting circuit 10 detecting the operation of the oscillator 4 is connected to the frequency divider 6. Just after the application of power supply, the CR oscillation circuit is operated with a zero output of the circuit 10 and a battery voltage is directly applied to the crystal oscillator via a switch 13 of intermittent operation. When the oscillator 4 starts oscillation, the output of the circuit 10 goes to 1, the intermittent operation of the switch 13 by the circuit 2 is stopped and a constant voltage lower than the battery voltage is applied to the oscillator 4 via a switch 15.

Inventors

• 👤 Terubumi Oshitari
• 👤 忍足　光史

Bibliographic Details