SN74LVC244A: Part used with 3.3V input and 1.8V VCC

Nanjunda M

Expert 2485 points

Part Number: SN74LVC244A

Hi,

We have used SN74LVC244APW with TPS3808G33DBVR for some Reset circuit.

Schematics is as below:

On board, while testing we are observing that the voltage at the input of the SN74LVC244A is 3.3V.

We are observing a 1.8V output on the SN74LVC244A (as of now).

Whether this will affect the IC operation/ performance?

Please let me know.

Thanks & Regards,

Nanjunda M

over 7 years ago

0 Dylan Hubbard over 7 years ago

TI__Mastermind 46295 points

Hi Nanjunda,

Thanks for using our device in this reset circuit! This device allows inputs up to 5.5 V. Translating from 3.3 V to 1.8 V is perfectly fine.

0 Nanjunda M over 7 years ago in reply to Dylan Hubbard

Expert 2485 points

Hi Dylan,

I too thought the same. But one of my SN74LVC244A went bad today.(We were testing it from past few days.)

So just thought will this matter /contrinbute to that.

Thanks & Regards,
Nanjunda M

0 Dylan Hubbard over 7 years ago in reply to Nanjunda M

TI__Mastermind 46295 points

Hi Nanjunda,

This shouldn't be a factor in that failure. It's used in applications like this quite often. Are you operating the device close to any of the abs max ratings (specifically current-wise)?

0 Nanjunda M over 7 years ago in reply to Dylan Hubbard

Expert 2485 points

Hi Dylan,

No, we are not using anything near abs max. All are with few mA inputs.

Thanks & Regards,
Nanjunda M

0 Dylan Hubbard over 7 years ago in reply to Nanjunda M

TI__Mastermind 46295 points

Hi Nanjunda,

Okay that's good, If you are staying under the abs max ratings then this device will have no issues with a 3.3 V input.

Logic

Logic forum

SN74LVC244A: Part used with 3.3V input and 1.8V VCC