| 摘要 |
PURPOSE:To make it possible to operate an electronic timepiece stably and accurately even if a temp. is changed, by properly setting a MOS transistor generating fixed bias voltage supplied to a current controlling transistor. CONSTITUTION:An electronic timepiece 1 is equipped a crystal oscillating circuit 5, a battery 6, a frequency dividing circuit 10 and a display circuit 11. A current voltage control circuit 12 controls a current Ia and voltage Va flowed to the oscillating circuit 5 and the frequency dividing circuit 10 and has a constant voltage generating circuit 14 generating fixed bias voltage VB supplied to a current controlling transistor 17. The constant voltage generating circuit 17 consists of the D-MOS transistor 18 of a source.gate shortcircuit and the E-MOS transistor 19 of a gate.drain shortcircuit and constant voltage is generated from these connecting points. By setting the K value and the threshold voltage of the transistors 18, 19, the temp. compensation of the electronic timepiece is carried out. |
