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I'm no expert in this area, but expressions within { } are evaluated before simulation, which is not what you want, of course. What if you use ordinary ( ) instead?

I’m frustrated by failure of a time measurement I’m trying to make.

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My circuit generates a pulse train with parameterized width, Pw.

I want to measure a delay, from a rising edge of one node, N0, to the next rising edge of another node, Nx.

Due to a filter action, the amplitude of V(nx) is dependent upon a resistor whose value is stepped, from run to run.

Because of that, I want to make the trigger (target) amplitude a variable, say 90% of the MAX() amplitude of node Nx.

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1. .meas VNx MAX V(Nx) FROM {5*Pw} TO {25*Pw}
2. .meas T1 TRIG V(N0)=2.25 TD=3u RISE=1 TARG V(Nx)=250m TD=3u RISE=1

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Measurement 1 correctly returns a peak value from say 0.5V to 4.5V.

Measurement 2 returns a time that’s too close to the stat of Rise, instead of near the peak level.

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T1 Fails if I use this instead:

3. .meas T1 TRIG V(N0)=2.25 TD=3u RISE=1 TARG V(Nx)={0.9*VNx} TD=3u RISE=1

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Help??

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Dave

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