Part Number: SN74LVC1G14-EP
A client of mine is using a SN74LVC1G14-EP as an analog discriminator where it is driven by an analog op amp and powered from 3.3v. The power rail and ground are stable.
The SN74LVC1G14-EP is acting like an inverting analog op-amp with a gain of around -1.5.
For example, if a sine wave is present on pin 2, pin 4 (the output) is an inverted sine wave of slightly higher amplitude. This exists even down at 10kHz. If the input is changed to a square or triangle wave, the output is similar shape, but inverted.
The part marking is "SBLM".
Is there any condition where this part should act like that ?
Is there an underside part marking or any other identifiable checks for counterfeit ?