| 摘要 |
An oscillator creates a reference voltage based on a pulse signal corresponding to an oscillation output of a crystal oscillation circuit and controls a supply voltage to the crystal oscillation circuit according to the reference voltage. A control signal creating circuit creates a control signal based on the pulse signal and reference voltage generating circuits that control the reference voltage based on the control signal. The control signal creating circuit creates a low-level control signal when the pulse signal is in a low level, creates a high-level control signal when the pulse signal is in a high level, and prevents transition of the control signal from the high level to the low level. |
