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
0 h4 c5 X" T4 y/ i4 w.meas tran period trig V(out1) val=0.9 rise=50 targ V(out1) val=0.9 rise=100
' T1 M' ?3 c# g* Y0 A8 L.meas tran f param='50/period'
! e" c5 e, S7 I; t以及搭配.tran 0.1n 100n sweep in 0 1.8 0.1之語法

& n* z6 X7 F) s  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
8 g& z% W% i/ |不知是我那邊的語法沒有打好
" m  A" `" i9 T2 e; ~! w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
9 F$ G; ?# P3 Q以下是我的spice code
8 V  e% d$ {# R! L# I
1 @3 H2 Z% j9 e7 G.PARAM
* F5 H& E- C' N2 K! C: b- I9 y3 `.GLOBAL gnd
+        vdd
2 C' `$ }& a6 _2 L. j9 f.SUBCKT vco_nm in out1 out2 vbaise
MM0 out2 out1 vdd vdd pch W=5u L=180n M=80
MM1 out1 out2 vdd vdd pch W=5u L=180n M=80
+ e* v. ]( l7 F5 k3 y% lMM5 in out2 in vdd pch W=5u L=180.00n M=150
* `2 l' i* m. b& n4 sMM4 in out1 in vdd pch W=5u L=180.00n M=100
( Y( p1 G! ~- AMM6 net32 vbaise gnd gnd nch W=5u L=180n M=60
8 C# Q; f+ f  a/ t  aMM2 out2 out1 net32 net32 nch W=5u L=180n M=60
MM3 out1 out2 net32 net32 nch W=5u L=180n M=60
) s6 D  x  c1 N' e& iLL0 out1 out2 0.8n $[LP]
4 W# K7 m& Z6 f  I! ~, w.ENDS

$ r7 H  t+ k# gx1 in out1 out2 vbaise vco_nm
v1 gnd 0 dc 0v
# t  [1 a2 A: z- d9 gv2 vdd 0 dc 1.8v
, {" K1 Y5 B" x2 d! [1 F$ bv3 in 0 pwl 0n 0v 100n 1.8v
v4 vbaise 0 dc 1.8v

c1 out1 gnd 0.5p
c2 out2 gnd 0.5p
' T; V. p& X% ]7 E.meas tran period trig V(out1) val=0.9 rise=50 targ V(out1) val=0.9 rise=100
1 F% ?0 w5 Q" c6 |.meas tran f param='50/period'

.tran 0.1n 100n sweep in 0 1.8 0.1
4 p. W! }! U7 C0 o: c3 N0 m.option post
.end

poseidonpid

.tran 0.1n 100n sweep in 0 1.8 0.1
/ G) t! ]2 \9 h! k3 A這一行不會動作，當然會看到的都一樣啊~
改成
" T0 J/ x5 H$ n- N2 S. n6 Q  ^v3 in 0 0
' H2 U+ d. B, n, \2 r) D# @.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
' L1 T. N7 T# `( d輸出波形如下

poseidonpid

.PARAM
.GLOBAL gnd
+        vdd
/ Q( C) m" i; B8 z+ V0 L.SUBCKT vco_nm in out1 out2 vbaise
MM0 out2 out1 vdd vdd pch W=5u L=180n M=80
MM1 out1 out2 vdd vdd pch W=5u L=180n M=80
0 b0 E' z. {, W# X$ }8 G9 jMM5 in out2 in vdd pch W=5u L=180.00n M=150
& c1 D/ L/ M  I# Z) WMM4 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
+ Q3 G; W3 ?% V# V7 v4 PLL0 out1 out2 0.8n $[LP]
# m; G2 x8 o8 y, d; {8 ].ENDS
$ b& v1 a# B( x# c3 K8 v1 {
x1 in out1 out2 vbaise vco_nm
v1 gnd 0 dc 0v
v2 vdd 0 dc 1.8v
  X: |( y( o0 g/ _0 h. Y4 zv3 in 0 pwl 0n 0v 100n test
v4 vbaise 0 dc 1.8v
3 P; b3 ^8 x0 l
.param test=1.8

* Z; U- j) u$ {. X, }3 G  h
c1 out1 gnd 0.5p
c2 out2 gnd 0.5p
. P5 U8 o$ q/ ?: i% H.meas tran period trig V(out1) val=0.9 rise=50 targ V(out1) val=0.9
# i' V* R& `7 ~
2 g  A! w$ Q' @: G0 g& k7 @7 q4 brise=100
8 X. N  I' f6 x/ T* r7 k" d( c.meas tran f param='50/period'

9 A( O9 y: d7 {, |) B.tran 0.1n 100n sweep test 0 1.8 0.1
.option post
; y, G5 e# _: ?# P3 b  ]& d) E/ }  M.end

# Q- D+ L+ ]: N$ D! p/ S  _+ S' \這樣就可以了
1 M$ r' `7 i' x, k- K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

謝謝大大的分享~知識因分享而壯大！

k9966809

又學習到一課 謝謝大大的分享

becka0704

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