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SN74ABT2240A: What happens if VI > VCC ? (Bus hold function using and side effect)

Part Number: SN74ABT2240A
Other Parts Discussed in Thread: SN74LVC8T245, SN74HCS14, SN74AHCT240, SN74AHCT540, SN74AHCT04

Hi Ti team,

My project seems to be in trouble, 5VDD  cannot be shut down properly when OVP occurs. I probably know the root cause is clamping diodes. Therefore,  I seek some solutions to avoid the voltage from Vin cross to VCC or Vout (Vi > VCC). The following points are the ideas I got from searching for E2E, and please help check if they are correct.

1. Choosing without positive clamping diode. 

2. Choosing IC which having Ioff (partial power down)

3. Choosing bus-hold IC.( Remember to remove the pull-up resistance if there had before)

4. Chossing a  Zener diode at VCC. (a bit like bus-hold topology)

If I take the IC of SN74ABT2240A as an example, can I prevent the phenomenon of leakage current into any output and VCC  when VCC=0V? Or do I need to search for another suitable solution?  

Thanks ~