+ H h- i& W! ]* { **error** no convergence in operating point , V5 d* Q; U" f& ~- e6 M5 c( h9 S% [4 g" K) d# ~5 u! d4 L' B
我給的initial condition只有VCO的震盪電壓.還有迴路濾波器進入VCO的vctrl. [8 i2 A; } O6 @6 N' T0 U
相同的訊號我再presim都可以跑.但是換到postsim就掛了!( d* l2 L& Q- v5 F
4 M1 Y2 S( g# V r6 k請問有人有遇過類似的問題嗎? ! @7 ?: v0 N+ S" r+ [謝謝!!作者: ccy3065 時間: 2008-12-31 01:20 AM
我試著把每一個block依序拿掉去跑POSTSIM.* E4 G1 Q* x% K, z1 U, q; D6 _3 {% v
發現是VCO那個電路的問題" e/ J, y/ z& e2 K0 ^# f6 T( a0 }
也就是 PFD+CP+Loop Filter---->OK! ) p- F8 j2 _; Q3 |. @8 z- D一加上VCO就掛了! 8 F/ V# p6 @9 S$ V8 \ j但是我有單獨跑過VCO的postsim是可以動的." G b7 D+ X: C
請問在跑postsim的時候. + ?. v2 G2 ^ L* minitial condition還要給哪些額外的條件呢? $ w0 a1 M U8 }, @+ T謝謝!作者: jameshsiao 時間: 2008-12-31 11:11 AM
Maybe the phase detector model either has no DC operating point or because it has an infinite; ~$ F A$ l" F+ `5 Z. i
number of operating points.