eldo_user

Specifying Simulation Output
Safe Operating Area Examples
SOA check
.width out=80
.model n npn
r1 in out 10k
c1 out 0 1p
q1 c b 0 0 n
rl c vdd 1k
vin in 0 pwl 0 0 1n 10 20n 10 21n 100
vdd vdd 0 5
vb b 0 pwl 0 -1 40n 1
.setsoa d r1 i=(*, 3m)
.setsoa m n ic=(-1u, 3m)
.setsoa e IC(q1)/IB(q1)=(*, 100)
.checksoa
.option eps=1u
.tran 1n 40n
.plot tran v(out)
.plot tran i(r1) ib(q1) ic(q1)
.end
This produces the following warning on screen (or in the .log file, if you are simulating
in background):
Warning 1897: SOA DETECTION: See output file soa.chi for details.
The following results will be obtained in the .chi file:
0*SOA check
0**** SOA INFORMATION (TRANSIENT ANALYSIS)TEMPERATURE = 27.000 DEG C
0******************************************************************
*| R1:
*| I(R1)
*| X AXIS WINDOW: [ 20.32351N 31.73644N ]
*| Value superior to 3.000000e-003 (up to 8.691883e-003 )
*| IC(Q1)/IB(Q1)
*| X AXIS WINDOW: [ 28.46930N 32.91922N ]
*| Value superior to 1.000000e+002 (up to 1.155804e+002 )
*| Q1: model=N
*| IC(Q1)
*| X AXIS WINDOW: [ 35.33005N 40.00000N ]
*| Value superior to 3.000000e-003 (up to 4.972460e-003 )
Total number of SOA instances : 3
Total number of violations : 3
• In the following example, two cards will be kept: the one in xsub corresponding to X1;
and the top level card .SETSOA D X1.R1.
Eldo® User's Manual, 15.3 347