JPS5487267A - Electronic watch - Google Patents

Abstract

PURPOSE:To maintain the operations such as oscillations or frequency division stable without increasing the power consumption by increasing the gain of the amplifier of an oscillating circuit unit upon the instant reduction in the voltage of a battery, which accompanies the drives of a motor, a lamp, a buzzer and the like. CONSTITUTION:When the output of a pulse composing circuit 3 is at an ''L'' level, the battery voltage is so sufficiently high, when a motor 5 is not driven, that an oscillating circfit 1 and a frequency dividing circuit 2 are operated stably. When motor driving signals are generated from the pulse composing circuit 3, a drive circuit 4 drives the motor 5. At this time, a high current flows to remarkably reduce the battery voltage, but the output of the pulse composing circuit 3 is partially fed back the oscillating circuit 1. As a result, the gain control signals of the oscillating circuit take an ''H'' level, and the gain of the amplifier of the oscillating circuit 1 is so increased that the stable oscillations are continued irrespective of the reduction in the battery voltage. When the drive of the motor 5 is ended, the oscillating circuit 1 continues again its oscillations with the initial low gain.