SN74LVC16245A: Leave input floating

Shota Mago

Expert 8490 points

Part Number: SN74LVC16245A

Hi team,

My customer will use SN74LVC16245A and they leave some unused input pins floating.

It it okay for the device or is connecting to GND/VCC essential?

I'm looking forward to hearing back from you.

Best regards,

Shota Mago

over 5 years ago

0 Shota Mago over 5 years ago

TI__Expert 8490 points

Hi team,

I noticed that datasheet shows "(1) All unused inputs of the device must be held at VCC or GND to ensure proper device operation. Refer to the TI application report, Implications of Slow or Floating CMOS Inputs, literature number SCBA004.".

Also bellow thread suggested to use SN74LVCH16245A which has bus-hold feature.

https://e2e.ti.com/support/logic/f/151/p/789008/2927153?tisearch=e2e-sitesearch&keymatch=SN74LVC16245A%20leave#2927153

If you have additional comment for SN74LVC16245A and SN74LVCH16245A, please let me know.

Otherwise, you can close this thread.

Best regards,

Shota Mago

0 Michael J Schultis over 5 years ago in reply to Shota Mago

TI__Mastermind 25015 points

Hello Shota,

Yes, your follow up post is correct that all unused inputs must be defined. Furthermore with a transceiver function such as this one where each output is an I/O, there are also inputs connected to each output which must be defined when the device is set to 3-state mode.

Best,
MIchael

Logic

Logic forum

SN74LVC16245A: Leave input floating