Why I can't get the wave of the GM of a transistor?

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wjxcom

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Hi all: I design a rail-to-rail OPA, I use this command to get the GM of the transistor( use Hspice to perform simulation):

.PROBE DC GMN1=LX7(XOPA.MN1) GMP1=LX7((XOPA.MP1)

but after the simulation, I can't find the GMN1, GMP1 or LX7(XOPA.MN1),LX7((XOPA.MP1)

I don't know why! help me, please!!!

the netlist can be found at the attachment! thanx!!
 

I have same question before. I thought Hspice might caculate the gm once at initial status for OP.

Added after 7 seconds:

I have same question before. I thought Hspice might caculate the gm once at initial status for OP.
 

    wjxcom

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Hi, waxtomato: I have cutoff the .op command, and I can not find the the wave of the GM at the awave yet! the netlsit is:
*.OP
.PROTECT
.DC VCM 0V 5V 0.01V
.LIB 'D:\EXERCISE\DESIGNOPA\CSMC06\CSMC.LIB' TT
.PROBE DC GMN1=LX7(XOPA.MN1) GMP1=LX7((XOPA.MP1)

Help me please, thanx!!
 

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