how to measure the current in subckt

[santoshchiniwar]

hi,
how can I measure the current and plot the graph for subckt in hspice code.. i want to measure the drain current of multigate FET

 

[erikl]

.PRINT TRAN I(hier1.hier2.hier3.FET_name)
.PLOT TRAN I3(hier1.hier2.hier3.FET_name)

hier1 (2,3) are the hierarchy names. I=I1 and I3 are the S and D currents, according to the node order of the FET.

Not sure if this works, but should be close to what will work. My hspice experience is long ago, sorry!

 

[santoshchiniwar]

hi,
Could you please give me an example for measuring the current between the nodes in subckt ...

 

[erikl]

Between which nodes?

 

[ankitgarg0312]

for measuring current from ports of subckt, please use

.subckt temp a b
m1 a b 0 0 nch l=1u w=1u
.ends

x1 in out temp

.print isub(x1.a) $ print in lis file
.probe isub(x1.a) $ plot is tro file

 

[santoshchiniwar]

hi,
Actually mentioned above method didn't worked

code is as follows
** subckt for NMOS **

.subckt DGNMOS NVd NVgf NVgb NVs
X.......X.....
.
.
.
.
mn1 NVd NVgf1 NVs 0 nmos w=60e-9 l='len'
mn2 NVd NVgb1 NVs 0 nmos w=60e-9 l='len'

En1 NVgf NVgf1 VOL= xxx
En1 NVgb NVgb1 VOL=xxx
ends

xnmos 2 1 gnd gnd DGNMOS
vds 2 gnd dc 1
vgs 1 gnd dc 0.6
vbs gnd gnd dc 0
.dc vds 0 1 0.01
.op
.plot dc
.print isub(x1.NVd) $ print 2 lis file

.alter gatesource voltage vgs=0.625
vgs 1 gnd dc 0.625
.alter gatesource voltage vgs=0.650
vgs 1 gnd dc 0.650

.end

i wanted to take current reading from xnmos (as we do for NMOS mosfet .plot dc i(mn) ) to make IV characteristic of this transistor

and my hspice is Hspui for windows c-2009-03

 

[ankitgarg0312]

please see below example, simulate in hspice and it will generate a .sw0 file .you can read that file in waveform viewer.
this example gives u direct VI characterstics of subckt(MOS). you need not use .alter as hspice allows two voltage sweeps ( see .dc statement below).

in ur example u have used .print isub(x1.nvd) it should be isub(xnmos.nvd)

EXAMPLE:


*** TITLE

.subckt nmos_ank d1 g1 s1 b1
m1 d1 g1 s1 b1 nch l=1u w=1u
.ends

xmos d g s b nmos_ank

vd d 0 0
vg g 0 1
vs s 0 0
vb b 0 0

.opt post probe
.model nch nmos

.dc vd 0 3 0.01 vg 0 3 0.1

.probe isub(xmos.d1)

.end

 

[santoshchiniwar]

hi,

thank you very much it worked