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SN74AVC4T774: SN74AVC4T774PW latch up when OE is held low during powerup

Part Number: SN74AVC4T774

We are using the Texas instruments SN74AVC4T774PW a as a lever shift from 1.8V to 3.3V, I see in the datasheet they say to hold Output Enable High until VCCA and VCCB are powered up. What happens if output enable is always tied to ground?


What would happen if the input signal is pulled up the same voltage as VCCB? In our situation we have VCCA = 3.3V come up immediately and then VCCB = 1.8V powers up after about 10ms.



  • Latch-up can happen only when you exceed the absolute maximum ratings.

    When /OE is low, the outputs are enabled. When the supplies are below the recommended minimum, the device might not work correctly, including the DIR pins. So you might get wrong voltages at any of the I/O pins.

    You can tie /OE low if you do not care about the state of the I/Os during power up.