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
; h# R* ~5 \- p% V* ^.meas tran period trig V(out1) val=0.9 rise=50 targ V(out1) val=0.9 rise=100
# c0 Y4 Y2 V8 b* S6 o" q% ?.meas tran f param='50/period'
以及搭配.tran 0.1n 100n sweep in 0 1.8 0.1之語法

8 ~. p9 g: r; r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
0 T& ]0 j. S8 y請各位前輩可給點意見...謝謝
以下是我的spice code

.PARAM
8 Q: m2 }6 d/ {4 M4 y.GLOBAL gnd
" i* i1 O' [7 ]7 T  p- w+        vdd
.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
MM5 in out2 in vdd pch W=5u L=180.00n M=150
6 x; k# M; Z; i9 T/ B! 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
  B4 c  y" }* oMM3 out1 out2 net32 net32 nch W=5u L=180n M=60
LL0 out1 out2 0.8n $[LP]
; ]9 L) g4 U, O$ b2 r! J8 o.ENDS

3 e$ _3 w: C) s# U/ }6 v4 cx1 in out1 out2 vbaise vco_nm
v1 gnd 0 dc 0v
6 M+ |$ o  [/ \0 N- mv2 vdd 0 dc 1.8v
- p# @- T" \) Y) Jv3 in 0 pwl 0n 0v 100n 1.8v
: }' _& G7 e& B; Pv4 vbaise 0 dc 1.8v

c1 out1 gnd 0.5p
. F- ?( `* b, I5 pc2 out2 gnd 0.5p
.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'
* h% `5 L3 H1 F3 w
% ~: D9 m% v! G.tran 0.1n 100n sweep in 0 1.8 0.1
.option post
+ h% p1 ^0 @6 A2 n. c" M) d.end

becka0704

感謝分享！

k9966809

又學習到一課 謝謝大大的分享

deltachen

謝謝大大的分享~知識因分享而壯大！

poseidonpid

.PARAM
$ q( E! X  M( E9 M.GLOBAL gnd
+        vdd
2 n; o" o! b" B5 Y. `.SUBCKT vco_nm in out1 out2 vbaise
; h# t# s/ e( u# qMM0 out2 out1 vdd vdd pch W=5u L=180n M=80
MM1 out1 out2 vdd vdd pch W=5u L=180n M=80
0 x; d( H4 \! t- z9 J1 ^MM5 in out2 in vdd pch W=5u L=180.00n M=150
: O$ l5 {1 U! \7 V* A- I- }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
" E# f3 U5 S( z0 U* V' DMM3 out1 out2 net32 net32 nch W=5u L=180n M=60
LL0 out1 out2 0.8n $[LP]
.ENDS
8 {6 L: O8 w; b
  ^( H* w: j( _x1 in out1 out2 vbaise vco_nm
+ l" ]2 A9 S$ ~: av1 gnd 0 dc 0v
: k: ~. q. c9 u, h+ @- r7 }v2 vdd 0 dc 1.8v
0 n  c' M. y! R8 Q% jv3 in 0 pwl 0n 0v 100n test
" Y; q* j2 t- A. ]" Uv4 vbaise 0 dc 1.8v

.param test=1.8

$ i' U, c% d8 c* D/ h; ]' x
2 K5 ^; U+ H# R; i) L: o3 ~c1 out1 gnd 0.5p
) ^+ s" O- a, m# Lc2 out2 gnd 0.5p
# p  O( F: ~# ^8 ~2 R0 \" B.meas tran period trig V(out1) val=0.9 rise=50 targ V(out1) val=0.9

rise=100
( v5 y/ a" d  D" {) {) r  V5 I.meas tran f param='50/period'
. Q* e. {8 C: {% z7 i. }: Q
.tran 0.1n 100n sweep test 0 1.8 0.1
.option post
8 [% B, a9 `+ e- c2 @5 h0 Y/ p.end

* f" W0 L8 D& K- E; y這樣就可以了
我有跑過模擬了~
8 z; z9 t6 m( j. _# m" K可以看到波形了~
* H" V; x) c: s* b' h( k$ L% j只是你的meas 指令好像有問題就是了~

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
( f. s$ Q5 e2 I輸出波形如下

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~
改成
) L8 @5 Q9 S' `  T8 G: Ev3 in 0 0
.tran 0.1n 100n sweep v3 0 1.8 0.1
應該就可以了