VCO V-F曲線量測問題

a016004

目前在研究LC VCO，從前人所提出用hspice 量測V-F曲線的方法得知利用
.meas tran period trig V(out1) val=0.9 rise=50 targ V(out1) val=0.9 rise=100
' ^) S! H* [6 _" _5 @2 X- h! w: _.meas tran f param='50/period'
以及搭配.tran 0.1n 100n sweep in 0 1.8 0.1之語法
5 @4 m9 a; k7 Q) i" E
但我照上敘的方法，結果量測的每一點電壓的變化出來的頻率都一樣
不知是我那邊的語法沒有打好
我的可變電容輸入(in)是用pwl指令，從0v掃到1.8v
請各位前輩可給點意見...謝謝
以下是我的spice code

; @7 w, \0 M/ v4 ]" n! c  J.PARAM
, x* ?' `: K  |4 ^$ z.GLOBAL gnd
+        vdd
.SUBCKT vco_nm in out1 out2 vbaise
0 ^2 O$ g) M; F0 u$ o7 FMM0 out2 out1 vdd vdd pch W=5u L=180n M=80
0 n2 w8 ~; e9 N: J$ d: z- G3 iMM1 out1 out2 vdd vdd pch W=5u L=180n M=80
5 m1 e( O4 o8 i) Y3 N. v3 Y" VMM5 in out2 in vdd pch W=5u L=180.00n M=150
/ C# q$ y7 E& B; L& \MM4 in out1 in vdd pch W=5u L=180.00n M=100
* t" z( `" n2 a$ }MM6 net32 vbaise gnd gnd nch W=5u L=180n M=60
7 e7 v3 `/ t0 y& v$ o% w. J/ h- n# a7 kMM2 out2 out1 net32 net32 nch W=5u L=180n M=60
MM3 out1 out2 net32 net32 nch W=5u L=180n M=60
  ]$ S. u5 l$ b; ?' Z% y3 M2 @LL0 out1 out2 0.8n $[LP]
: {0 ]6 R7 l! w9 j  J3 w.ENDS

9 ?  x0 a& L, Jx1 in out1 out2 vbaise vco_nm
v1 gnd 0 dc 0v
$ y8 a4 i3 G7 Kv2 vdd 0 dc 1.8v
* z, v) r( ]7 o: ~) Iv3 in 0 pwl 0n 0v 100n 1.8v
5 A5 o* q5 L* A' \" av4 vbaise 0 dc 1.8v
6 v- N  k, Q. G5 p
" l$ m5 V8 u+ t! j( G3 @7 lc1 out1 gnd 0.5p
c2 out2 gnd 0.5p
5 L7 a' j& K) r$ Q+ y.meas tran period trig V(out1) val=0.9 rise=50 targ V(out1) val=0.9 rise=100
.meas tran f param='50/period'
* Z6 M0 Z9 h9 T5 z
.tran 0.1n 100n sweep in 0 1.8 0.1
.option post
.end

poseidonpid

.tran 0.1n 100n sweep in 0 1.8 0.1
這一行不會動作，當然會看到的都一樣啊~
/ x: _6 y5 A- J% u" U改成
3 J0 z% }" r' u( }2 ~v3 in 0 0
.tran 0.1n 100n sweep v3 0 1.8 0.1
+ @) }- ^' a- E% N4 s4 k7 i" I應該就可以了

a016004

我有照樓上的前輩所說的下去做
但跑出來量測不到波形
輸出波形如下

poseidonpid

.PARAM
; Z6 G! Q* W9 x( K' T1 M8 `8 P.GLOBAL gnd
6 P7 {0 h4 I$ j! _, L+        vdd
  u% ~2 @6 }3 ~  S2 {+ Z: L1 y+ N.SUBCKT vco_nm in out1 out2 vbaise
7 Y( o* W. P7 n+ Y% v/ yMM0 out2 out1 vdd vdd pch W=5u L=180n M=80
9 _6 d) o% j4 p- _MM1 out1 out2 vdd vdd pch W=5u L=180n M=80
MM5 in out2 in vdd pch W=5u L=180.00n M=150
MM4 in out1 in vdd pch W=5u L=180.00n M=100
MM6 net32 vbaise gnd gnd nch W=5u L=180n M=60
MM2 out2 out1 net32 net32 nch W=5u L=180n M=60
MM3 out1 out2 net32 net32 nch W=5u L=180n M=60
* m- E5 E2 p8 R& O9 kLL0 out1 out2 0.8n $[LP]
.ENDS

x1 in out1 out2 vbaise vco_nm
" k* G* s( F: S$ ?* p; l7 |v1 gnd 0 dc 0v
' T3 c2 n+ u; i  @v2 vdd 0 dc 1.8v
) I; c( {1 H: Z; G1 c; `4 Uv3 in 0 pwl 0n 0v 100n test
v4 vbaise 0 dc 1.8v

.param test=1.8
" b7 y+ z7 x$ D

c1 out1 gnd 0.5p
2 D/ T- q* K6 u' F: uc2 out2 gnd 0.5p
- x9 x- i  c3 h.meas tran period trig V(out1) val=0.9 rise=50 targ V(out1) val=0.9
; ^4 R* Y# Q6 d8 E& k; d7 ?  {
rise=100
.meas tran f param='50/period'

# T! `/ G6 S# X8 Q" i.tran 0.1n 100n sweep test 0 1.8 0.1
5 w- h% e  ?# H.option post
.end

$ @; h; b7 W/ y3 U2 l這樣就可以了
3 |3 D+ i& N5 A& L+ m0 ?" K4 B我有跑過模擬了~
可以看到波形了~
只是你的meas 指令好像有問題就是了~

deltachen

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k9966809

又學習到一課 謝謝大大的分享

becka0704

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