wccheng
Full Member level 5
lc oscillator hspice tran time
Dear all,
I am using tsmc 0.13um to design one differential LC-VCO oscillator. I am using HSpice to simulate the .tran. The transistor uses the model provided by tsmc. The other components using ideal model, for example: L, C, R. I have set the trasisent step small enough. Moreover, I have add the starup pulse for the VCO to start up the oscillation.
However, the oscillator does not oscillate. How could I solve it? Even it can start up at first time, it will dampling out finially. Even I increase the size of the cross coupled transistor size or current source. It could not oscillate continuously. How could I solve it?
thanks
wccheng
Dear all,
I am using tsmc 0.13um to design one differential LC-VCO oscillator. I am using HSpice to simulate the .tran. The transistor uses the model provided by tsmc. The other components using ideal model, for example: L, C, R. I have set the trasisent step small enough. Moreover, I have add the starup pulse for the VCO to start up the oscillation.
However, the oscillator does not oscillate. How could I solve it? Even it can start up at first time, it will dampling out finially. Even I increase the size of the cross coupled transistor size or current source. It could not oscillate continuously. How could I solve it?
thanks
wccheng