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
) r9 n3 \1 T" g4 q.meas tran period trig V(out1) val=0.9 rise=50 targ V(out1) val=0.9 rise=100
# {: k% e  Y3 Z7 z& C. k.meas tran f param='50/period'
以及搭配.tran 0.1n 100n sweep in 0 1.8 0.1之語法
2 B& y/ ]$ U3 D: F# i" F* D0 R2 b
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
8 B* S4 w' O( k% y: U  E我的可變電容輸入(in)是用pwl指令，從0v掃到1.8v
! h( E/ E- W5 j! e2 t: w( `% C請各位前輩可給點意見...謝謝
以下是我的spice code

.PARAM
.GLOBAL gnd
- }4 }/ F( d, i' u7 p& e+        vdd
.SUBCKT vco_nm in out1 out2 vbaise
MM0 out2 out1 vdd vdd pch W=5u L=180n M=80
2 Y, |! n+ ^' i$ E* A6 hMM1 out1 out2 vdd vdd pch W=5u L=180n M=80
) ?5 `% w! Z6 p( jMM5 in out2 in vdd pch W=5u L=180.00n M=150
4 N2 u# o: G5 L+ q* iMM4 in out1 in vdd pch W=5u L=180.00n M=100
1 I' y+ Z. s5 B- @* e! u6 H& P' VMM6 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
2 E( o9 ?) U/ t6 WLL0 out1 out2 0.8n $[LP]
0 Q1 N+ {) w0 g* q- J# G.ENDS
; ~- ?% g0 {, J- X& G9 S2 h
% Q1 M; ]3 c% u, j4 M9 X' v4 ]" Vx1 in out1 out2 vbaise vco_nm
v1 gnd 0 dc 0v
+ h5 n0 _1 w! f. z6 c. n( ev2 vdd 0 dc 1.8v
v3 in 0 pwl 0n 0v 100n 1.8v
v4 vbaise 0 dc 1.8v

; Q- N# R* q+ o+ M7 {* M) Lc1 out1 gnd 0.5p
c2 out2 gnd 0.5p
.meas tran period trig V(out1) val=0.9 rise=50 targ V(out1) val=0.9 rise=100
. V: F  }3 @+ U2 i. Z5 e.meas tran f param='50/period'

.tran 0.1n 100n sweep in 0 1.8 0.1
6 p. E% ]% q  }! J.option post
7 [6 }0 g  g- J+ j5 F3 g.end

poseidonpid

.tran 0.1n 100n sweep in 0 1.8 0.1
$ [" D3 j8 F8 @& \8 T  i  Z這一行不會動作，當然會看到的都一樣啊~
改成
' I& }0 G9 r# H$ [4 `% lv3 in 0 0
7 E" o4 n8 r! ]6 ~9 q# e- @.tran 0.1n 100n sweep v3 0 1.8 0.1
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
.GLOBAL gnd
! x' L% ?8 Y. ?% n; x+        vdd
.SUBCKT vco_nm in out1 out2 vbaise
6 J2 h2 E6 n9 u4 w9 K- oMM0 out2 out1 vdd vdd pch W=5u L=180n M=80
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
LL0 out1 out2 0.8n $[LP]
.ENDS

x1 in out1 out2 vbaise vco_nm
v1 gnd 0 dc 0v
v2 vdd 0 dc 1.8v
+ b0 H3 ~  p+ @; J7 X5 ?* Vv3 in 0 pwl 0n 0v 100n test
- _2 c* i% O$ Q4 X  k' Q+ E$ B% vv4 vbaise 0 dc 1.8v

.param test=1.8

( }3 f3 N+ L' V* a/ p- `% p
c1 out1 gnd 0.5p
c2 out2 gnd 0.5p
/ C6 f; T4 K" U$ ?% D6 |) }.meas tran period trig V(out1) val=0.9 rise=50 targ V(out1) val=0.9

& |; X$ f" w9 L4 S/ vrise=100
.meas tran f param='50/period'

& W- V' Z3 k# z& i" K/ i) K.tran 0.1n 100n sweep test 0 1.8 0.1
.option post
.end
! G' H3 b& |3 H, Z5 l  p" r
+ e3 ]: W. d  ^2 L3 f! j這樣就可以了
我有跑過模擬了~
可以看到波形了~
; O1 q* w2 ~. a$ z$ B# F1 ?只是你的meas 指令好像有問題就是了~

deltachen

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k9966809

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becka0704

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