Patent ID: 9628022
Date: 2017-04-18
CPC Classifications: H03B,Y10T

Claim:
1. An oscillation circuit comprising: a first terminal which is connected to one end of a resonator; a second terminal which is connected to the other end of the resonator; an oscillation unit which is electrically connected to the first terminal and the second terminal, wherein the oscillation unit includes at least one first electronic element of which a first end of the first electronic element is electrically connected to the first terminal or the second terminal, and the oscillation unit is operable in a normal mode or a test mode; a first voltage generation circuit that includes a control voltage generation circuit and an overdrive voltage generation circuit, wherein the control voltage generation circuit generates a control voltage signal based on a temperature, the overdrive voltage generation circuit generates an overdrive voltage signal that has a voltage value less than the maximum rated voltage of the first electronic element and greater than a voltage outputted by the control voltage generation circuit, and an amplitude of the control voltage signal is less than that of the overdrive voltage signal; and a first switching unit configured to electrically couple and decouple the oscillation unit to one of the control voltage generation circuit and the overdrive voltage generation circuit based on an operation mode of the oscillation unit, wherein the first switching unit is connected to a second end of the first electronic element, wherein, in the normal mode, the first switching unit connects the second end of the first electronic element to the control voltage generation circuit to apply the control voltage signal based on the temperature to the first terminal and the second terminal by way of the first electronic element, wherein, in the test mode, the first switching unit connects the second end of the first electronic element to the overdrive voltage generation circuit to apply, to the first terminal and the second terminal by way of the first electronic element, the overdrive voltage signal having the voltage value less than the maximum rated voltage of the first electronic element and greater than the voltage outputted by the control voltage generation circuit, wherein the at least one first electronic element includes two first electronic elements, wherein one of the first electronic elements has the first end connected to the first terminal and the other one of the first electronic elements has the first end connected to the second terminal, and wherein the overdrive voltage signal from the overdrive voltage generation circuit satisfies the following condition in which Vod is the voltage of the overdrive voltage signal, Vop1 is a maximum rated voltage of the one of the first electronic elements, Vmin is a minimum voltage value applied to the first end of the one of the first electronic elements by way of the first terminal, Vop2 is a maximum rated voltage of the other one of the first electronic elements, and Vmax is a maximum voltage value applied to the first end of the other one of the first electronic elements by way of the second terminal: