| 摘要 |
<p>PROBLEM TO BE SOLVED: To remove the temp. coefficient depending an amplitude and nonlinearity in a controlled amplitude oscillator and to provide the oscillator having high precision suitable for a low voltage operation by executing negative feedback control in a control circuit so that the clamp voltage of a second clamp element is equal to a reference voltage thereby equalizing the clamp voltages of a pair of clamp elements to the reference voltage. SOLUTION: An oscillation circuit 10 is provided with the first clamp elements Q3 and Q4 having a control terminal for controlling the amplitude of an output signal and constant current circuits Q5 and A6. A replica circuit 20 is connected to the oscillation circuit 10 in parallel and is provided with the second clamp element Q11 having the control terminal and the second constant current circuit Q8. A control circuit outputs control signals to the first and the second clamp elements based on the clamp voltage of the second clamp element and the prescribed reference voltage Vref in order to set the clamp voltage by the first clamp element to the prescribed voltage.</p> |
