D触发器 setup time 怎么仿真?
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vcc VDD! 0 exvcc
vss GND! 0 0
vD D 0 pwl 0 0 10n 0 10.01n exvcc 22n exvcc 23n 0 30n 0Td="delaytime"
vE E 0 pwl 0 exvcc 10n exvcc 10.01n 0 20n 0
VR R 0 pwl 0 exvcc 2n exvcc 2.1n 0
x1 VDD! Q out VDD! p33_ckt l=0.5 w=4
x2 out Q 0 0 n33_ckt l=0.5 w=2
.param delaytime=opt1(6n -6n 6n) exvcc=2.4v etemp=-40
.op
.tran .001n 30nsweep optimize=opt1 result=maxvout model=optmod
.meas tran setupt trig v(D) val='exvcc/2' rise=1 targ v(E) val='exvcc/2' fall=1
.meas tran maxvout max v(Q) goal='exvcc*0.9'
.alter FF.del lib '/home/xyhuang/EC1005Z_new/public/38nand_3.3vmosonly_v0p0.lib' TT.lib '/home/xyhuang/EC1005Z_new/public/38nand_3.3vmosonly_v0p0.lib' FF
.alter SS.del lib '/home/xyhuang/EC1005Z_new/public/38nand_3.3vmosonly_v0p0.lib' FF.lib '/home/xyhuang/EC1005Z_new/public/38nand_3.3vmosonly_v0p0.lib' SS
.alter SF.del lib '/home/xyhuang/EC1005Z_new/public/38nand_3.3vmosonly_v0p0.lib' SS.lib '/home/xyhuang/EC1005Z_new/public/38nand_3.3vmosonly_v0p0.lib' SNFP
.alter FS.del lib '/home/xyhuang/EC1005Z_new/public/38nand_3.3vmosonly_v0p0.lib' SNFP.lib '/home/xyhuang/EC1005Z_new/public/38nand_3.3vmosonly_v0p0.lib' FNSP
.end发现在执行.alter更换工艺角之前的第一次仿真能给出合理的结果,而在.alter后的仿真都abort....
bow
createdata tableto run sweep transient simulation,what's more, in the data table, you need to adjust D delayrelative to clock pin,the incremental step is determined by the precision requirment,so generally speaking, in the table, it must include incremental delta delay to approach the target setup time, and clock transition , and Q load pin capacitance. you also can put the delta delay outside of the table, but you must build many sub-circuitsto attain the target, but it has been processed parallel simulation.
Can not use sweep data=*** with model statement.
My purpose is to get minimum setup time, "sweep optimize" should be able to do this for me. But I got some error I can not fix.
Here is the error message:
**error** endpoints have same sign in bisection.
For delaytime= -1.00000E-08, maxvout=6.26407E-03.
For delaytime=1.00000E-08, maxvout=3.56375E-05.
Both of these are on the same side of the goal value maxvout=2.4300.
***** job aborted