| 摘要 |
PURPOSE:To form a buzzer circuit to a simple constitution and achieve the reliability of a watch with alarm by using the specified bipolar transistor incorporated into an IC chip for output of the buzzer circuit. CONSTITUTION:A bipolar transistor 3 for switching a buzzer circuit which consumes large current is incorporated into the chip of a transistor 2 in which the P minus diffused layer formed in the same process as the P minus diffused layer of the CMOS transistor 2 forming the main unit of the watch is the base, +N diffusion is the emitter and substrate 5 is the collector. Hence, the constitution of the buzzer circuit becomes simple and the reliability of the watch with alarm may be improved. |
