Hello,
I was testing a old control board and observed that, SN74AHC14 is seeing an input of +/- 7.5V. -7.5V is being clamped to -0.7. And 7.5V input is read as is. SN74AHC14 is supplied from 3.3V supply rail.
The device is working fine but the input voltage is above the specs as per datasheet
Is there a clamping diode for -Ve input voltages ?
And What is the absolute maximum input voltage on this device before it gets damaged ?
I am modifying this circuit in new board but I am wondering how this device is not damaged in the older board.