For ADUC（ARM7) family process, there are two parameters for ADC feature：
Absolute input voltage range and input voltage range。
for example, ADUC7034, the ADC parameter for voltage channel is ：
Absolute input voltage range：4～18V
Input voltage range:0~28.8V。
I don't know what is the difference between these two parameters.
I had created a case for support, but china support engineer can't answer it and not response me for long time.
I have to post it here to find if any one america engineer can resolve it.