How to use spectre calculator to return x value of a given y? Thanks.

Hi Andrew

 Using the cross function, it generates a number of points, where the lowest and the highest values are the right values that I want. why not the cross function is showing just two values instead of lot of points in the middle of those two points. I want the exact two x values where the y value is constant (e.g, -4.21). Thank you.

Hi Andrew

 How can I save the webforms in Cadence and later open it and work on it? I saved the forms as .grf file, but later when I open the .grf file, it only shows the expression, but no waveform is there. So, what is the right way to save waveforms and reopen it again at a later time? I have separate waveforms append together from different runs. Thank you. 

I suggest you read the forum guidelines. You've added two unrelated posts to an old thread, and the forum guidelines tell you not to do that. I'm short of time otherwise I'd split them up - but please don't do this as it makes things very confusing.

For your previous post, this is because you've passed 0 as the cross number (the third argument to cross). If you do this, it returns a list of all the crossing points. If you want the first, pass 1; if you want the last, pass -1. You must have had multiple crossing points.

For this one, I've no idea what a "webform" is, but assuming you are trying to save the waveforms, then the grf format actually saves the references to the waveforms - not the waveform data itself. You didn't say which version you're using (see the forum guidelines again), so hard to advise you - there are ways of exporting the data into a new database, but it's not that obvious precisely what you were trying to do or if it stands any chance of working in the version you're using.

Kindest Regards,

Andrew.

Hi Andrew, im using IC614 version, and when i try to use the cross function for something similar to was described i obtain this error:

*Error* crossMethod: can't handle crossMethod(2.502911e-05 2.4e-05 1 "either" nil nil)

Do you know whtas happening here?

Thanks in advance,

Francisco 

 Dear Fransisco,

 If your crossing threshold is 2.4e-05, have you verified by plotting the signal of interest that the waveform crosses 2.4e-05

Shawn

Hi Shawn,

Thanks for the quick answer. Yes, I've verified in the waveform that the signal crosses the specified point, and also my signal does not have any other rising or falling edge, this is a unique cross point and falling edge.

Thanks 

 Hi Fransisco,

 Might your provide the exact syntax of the calculator expression? One item I have occasionally noted is if the crossing point nearly coincides with the start or end of the waveform appears to results in a crossing error.

Hi Shawn,

 This is my calculator expression:

cross(IDC("/I0/icv0") 24e-6 1 "either" nil nil  ) 

My waveform has a constant  behavior, but after some point it starts to decrease, i want to measure the x value which  has 24u in Y axis (24u is close to the maximum value, less than 2% of difference).

Regards,

Francisco