仿真的时候出现如下错误信息：
SIMULATION LOG
==============
Design: C:\Program Files\Labcenter Electronics\Proteus 6 Demonstration\my\ADC\ADC.DSN
Doc. no.: <NONE>
Revision: <NONE>
Author: <NONE>
Created: 06/05/09
Modified: 06/05/09
Compiling source files...
Build completed OK.
Compiling netlist...
Linking netlist...
Partition analysis...
ERROR [PSM] : No model specified for 'U3'.
Simulation FAILED due to partition analysis error(s).
应该是缺少库文件，是不是低版本的proteus没有，而高版本的有呢？？？望大家多多指点，共同进步。谢谢！！！ | 
