Eldo MEASURE(EXTRACT) problem

[sinan]

I am trying to get tplh, tphl, trise and tfall times with the commands

..EXTRACT TRAN LABEL=RISE TRISE(V(out))
..EXTRACT TRAN LABEL=FALL TFALL(V(out))
..EXTRACT TRAN LABEL=tplh TPDDU(V(out),V(inp))
..EXTRACT TRAN LABEL=tphl TPDUD(V(out),V(inp))

inp: input net name, out: output net name

I get RISE and FALL times correctly but I could not get tplh and tphl
correctly,

for example I get
*TPHL = 2.1539N , while I should get something around 200ps ,
(both from plot results and calculation)

Also Eldo gives this error
"TPLH cannot be measured . Check your input netlist
wave1 has crossed the threshold 1 time(s) but wave2 has not (or before
wave1).
"
however I see from plots both wave1 and wave2 crosses the thresholds
I tried to increase my inputs delay, rise and fall times, did not work
out,

I get this error in some circuits, I am sure that EXTRACT commands are
true, but there must be some point I am missing
what can be the problem?

 

[S. Badel]

I am trying to get tplh, tphl, trise and tfall times with the commands

.EXTRACT TRAN LABEL=RISE TRISE(V(out))
.EXTRACT TRAN LABEL=FALL TFALL(V(out))
.EXTRACT TRAN LABEL=tplh TPDDU(V(out),V(inp))
.EXTRACT TRAN LABEL=tphl TPDUD(V(out),V(inp))

Don't you simply have inverted input and output in TPDDU/TPDUD ?

 

[sinan]

On Apr 5, 3:09 am, "S. Badel" <stephane.ba...@REMOVETHISepfl.ch>
wrote:

Don't you simply have inverted input and output in TPDDU/TPDUD ?

thanks, I tried them too (e.g. TPDDU(V(inp),V(out))) and again not the
correct result, but different results,
when I modify as

.EXTRACT TRAN LABEL=tplh TPDDU(V(inp),V(out))
.EXTRACT TRAN LABEL=tphl TPDUD(V(inp),V(out))
.EXTRACT TRAN LABEL=tplh2 TPDDU(V(out),V(inp))
.EXTRACT TRAN LABEL=tphl2 TPDUD(V(out),V(inp))

here results:

TPLH cannot be measured . Check your input netlist
wave1 has crossed the threshold 1 time(s) but wave2 has not (or before
wave1).
* TPHL = 2.1539N
TPLH2 cannot be measured . Check your input netlist
wave1 has crossed the threshold 1 time(s) but wave2 has not (or before
wave1).
* TPHL2 = 1.9239N

 

[sinan]

On Apr 5, 3:29 am, "sinan" <seen...@gmail.com> wrote:

On Apr 5, 3:09 am, "S. Badel" <stephane.ba...@REMOVETHISepfl.ch
wrote:



Don't you simply have inverted input and output in TPDDU/TPDUD ?

thanks, I tried them too (e.g. TPDDU(V(inp),V(out))) and again not the
correct result, but different results,
when I modify as

.EXTRACT TRAN LABEL=tplh TPDDU(V(inp),V(out))
.EXTRACT TRAN LABEL=tphl TPDUD(V(inp),V(out))
.EXTRACT TRAN LABEL=tplh2 TPDDU(V(out),V(inp))
.EXTRACT TRAN LABEL=tphl2 TPDUD(V(out),V(inp))

here results:

TPLH cannot be measured . Check your input netlist
wave1 has crossed the threshold 1 time(s) but wave2 has not (or before
wave1).
* TPHL = 2.1539N
TPLH2 cannot be measured . Check your input netlist
wave1 has crossed the threshold 1 time(s) but wave2 has not (or before
wave1).
* TPHL2 = 1.9239N

OK I see now, I looked output waves and tried to figure out which
combination gives 2.1539 and 1.9239 and found out that 2.1539
TPDUD(V(inp),V(out)) is the time between

rising input to decreasing output= 2.1539 TPDUD(V(inp),V(out)) (now it
makes sense, U for: V(inp) , D for: V(out))
and vice versa,

I should have used TPDUU and TPDDD instead,

thanks Badel again, it created an incentive to trace the error