Other Parts Discussed in Thread: TMUX1308
Hi team,
My customer is using CD74HC4051M96 in their air conditioner system for muxing NTC analog signals. And it is supplied by 5V.
What's the VIH for 5V supply? My estimation is 3.5V, since VIH=3.15V for 4.5V supply and VIH=4.2V for 6V supply, according to datasheet.
Question is the MCU who gives the digital signal is supplied by 3.3V, which means it will never be logic high to the mux. But according to customer their system works just fine for years. So the actual VIH for 5V supply must be lower than 3.3V.
This is confusing and customer thinks there might be potential risk.
Can you help confirm what's the VIH for 5V supply?
Thank you very much!
George