模擬OP時close loop出現奇怪的振盪現象

chungming

your input command mode rage is 0 to Vdd - (Vsg1+Vdsat5)
5 I% d3 O$ S8 y# uoutput command mode range is Vdsat7 to VDD-Vdsat6

+ W; M" B5 T6 c7 d* w6 u" nif this opamp is connected as unit gain buffer,
4 ?& W+ s( h+ Y5 |then the input & output command mode rage will be the same as vdsat7 to Vdd - (Vsg1+Vdsat5)
1 \% h1 k# B, x! Y$ |
: I: R" ?1 U& v% Fdon't trust simulation too much !
If you really want to design a real world opamp.

chungming

謝謝chungming大的回應
9 [5 l6 F7 Z; [) U6 N$ [/ o可以請問一下，考慮上述in/out common mode的情況下
接成UGB為何在模擬上仍可從foll ...
  k! U( I% ^# Z: \7 p, r/ U7 GBookert0921 發表於 2010-5-28 10:44 AM

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    呵呵~~~
依我看你的輸出波形並不是從"0到VDD"都可以follow阿
下限沒到0阿 況且接近下限時訊號已經沒follow了
+ \: e( X- u4 \$ O: ?(拖著長長的尾巴要很長時間才接近0)
並且接近VDD時 已經震盪了
% l+ g* X4 t9 V1 L0 D7 ^% ]怎麼會是有follow呢?