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pwl & timely bias trigger with different values

Charanraj Mohan

Hi, 

 I have two questions, as follows- 

1. Since I need to define pwl- data points (more in number) to bias a circuit, I don't want to put them in series like a long chain of pwl source, as the limit of a pwl source is only 50 datapoints. Is there any alternate where I can just simply define (voltage, time) in an instance and it generates the whole bias ???

2. I want to set a value to a variable that biases the gate of a transistor for some time in transient simulation and then after particular time, I want that this variable should change to another value. Is this possible ?? For example- I am running a transient simulation for 15us. Until first 5 us, I want gate of transistor, g = 2 V, then this variable should change to g = 3 V at 10u. Also again it can be changeable at a particular time. Is this possible ??

Thanks in advance.

Parents
    1. PWL sources in spectre do not have a limit of 50 points; that's just a limitation of the analogLib vsource/vpwl component because of the practicalities of how it is implemented. If on the vsource you choose to take the points from a file, or you use vpwlf, then the number of points is unlimited. I don't know what you mean by "is there any alternate where I can just simply... in an instance".
    2. Yes, this can be done. Use the "Dynamic Parameter" checkbox on the tran analysis form in ADE and then you can specify piece-wise values for changing parameters. Note that the change is instantaneous though, so you might want to set (for example) time=0, value=2; time=10u, value=2; time=10.1u, value=3 - and then in the tran options form, in the Misc tab, in the additionalParams enter param_step=10n - which means it will update more smoothly by changing by 0.1V every 10ns over the while 100ns of the transition.
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    1. PWL sources in spectre do not have a limit of 50 points; that's just a limitation of the analogLib vsource/vpwl component because of the practicalities of how it is implemented. If on the vsource you choose to take the points from a file, or you use vpwlf, then the number of points is unlimited. I don't know what you mean by "is there any alternate where I can just simply... in an instance".
    2. Yes, this can be done. Use the "Dynamic Parameter" checkbox on the tran analysis form in ADE and then you can specify piece-wise values for changing parameters. Note that the change is instantaneous though, so you might want to set (for example) time=0, value=2; time=10u, value=2; time=10.1u, value=3 - and then in the tran options form, in the Misc tab, in the additionalParams enter param_step=10n - which means it will update more smoothly by changing by 0.1V every 10ns over the while 100ns of the transition.
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