SN74AXC8T245: DIR pins

Vibhu Vanjari

Genius 11900 points

Part Number: SN74AXC8T245

Hello,

Do I need pullup /pulldown resistors on the DIR pins or can I connect directly to GND/VDD?

Thanks,

Vibhu

0 Clemens Ladisch over 6 years ago

Guru 327650 points

The DIR pins are high-impedance CMOS inputs, so an additional resistor has no effect (unless you intend to exceed the V_I absolute maximum rating).

0 ShreyasRao over 6 years ago in reply to Clemens Ladisch

Thank you Clemens !

Vibhu,

Pullup/pulldown resistors are our recommendation only and not a requirement.

0 Vibhu Vanjari over 6 years ago in reply to ShreyasRao

Hello Shreyas,

If using a pullup/pulldown, would a 10k be okay? From my understanding the value doesn't matter because the internal resistor is of a higher order.

Thanks,

Vibhu

0 ShreyasRao over 6 years ago in reply to Vibhu Vanjari

Vibhu,

10k is fine.

This FAQ below is relevant to DIR pin as well.

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