| 摘要 |
PURPOSE:To obtain the voltage wherein the fuctuation in battery voltage is reduced and to stabilize the operaion of a timepiece, by generating the selective divided voltage according to the battery voltage and suspending the voltage division at a prescribed voltage. CONSTITUTION:A voltage division circuit 5 which supplies a selective divided voltage V0 to a time measuring circuit 6, a voltage detection circuit 4 which changes the output signals phiBD1, phiBD2 to the circuit 5 when the source voltage Vb of the circuit 5 attains a preset value, and a reverse current preventing circuit 2 which disconnects the circuit 5 and a battery 1 at the same instant when the voltage Vb exceeds the voltage Va of the battery 1 are provided. The signal conversion circuit 7 of the circuit 5 outputs the control signals phi1-phi4 of transmission gates TG1-TG4 according to the respective signals phi. TG1-TG4 output the divided voltage V0 corresponding to the value of the source voltage Vb by changing over the connection between capacitors C1-C3 for voltage division and the output line of the output voltage V0. |
