SN74AXC4T774: SN74AXC4T774BQBR IO protection

Itai Cohen

Prodigy 40 points

Part Number: SN74AXC4T774

SN74AXC4T774BQBR IO protection

Will the SN74AXC4T774BQBR be damaged if i will work at the next scenario:

1)VCCB = 3.3V

2)VCCA = 1.8V

3)OE pin connected to GND through 10kOhm resistor.

4)B1- Input on VCCB side

5)A1- Output on VCCA side

6)DIR1 connected to GND (signal from B1 to A1)

The scenario- if i don't assert any signal at B1 side, but i'm forcing 'H' logic on A1 side does the IC will be damaged?

over 2 years ago

0 Dylan Hubbard over 2 years ago

TI__Mastermind 42640 points

Hi Itai,

If you violate any spec in the Abs max table, you will likely see damage to the device. What is driving a High at the output? If its another device then this will be bus contention which can cause damage.

0 Itai Cohen over 2 years ago in reply to Dylan Hubbard

Prodigy 40 points

The signal applied to A1 side is 1.8v derived from LDO output (no ABS max violation).

signal B1 has pull down resistor to GND.

if i will connect the 1.8v LDO voltage to A1 on the voltage translator will it damage the device?

What if the 1.8v from the LDO feed only to A1?

0 Dylan Hubbard over 2 years ago in reply to Itai Cohen

TI__Mastermind 42640 points

Hi Itai,

I would have to assume the power supply will source current beyond the recommended ratings and the abs max ratings.

Logic

Logic forum

SN74AXC4T774: SN74AXC4T774BQBR IO protection