| 摘要 |
PURPOSE:To obtain stable low voltage and reduce the power consumption of the electronic watch by constituting a voltage converting part with a reference voltage part and a current amplifier part which is inputted with a reference voltage and supplies a constant low voltage to a load being a low voltage part. CONSTITUTION:A power supply system for an oscillation part 1, frequency division part 2, display part 3 and display device 4 consists of two power source systems of a supply voltage system 7 and a low voltage system 6 which is decreased of the supply voltage by a voltage conversion part 5. The voltage conversion part 5 is constituted by a reference voltage part 51 consisting of a P channel MOS transistor 511 and resistance 512 and a current amplifier part 52 consisting of a P channel MOS transistor 521 ans uses the threshold voltage of the P channel MOS transitor 511 as the reference voltage. The current amplifier part 52 is inputted with the reference voltage and supplies a constant voltage to a load 6 by using the lease follower type circuit of the P channel MOS transistor. |
