BQ76PL455A-Q1: Are 100kΩ pull-ups to VIO at RX and TX mandatory?

K.Yaita

Part Number: BQ76PL455A-Q1

Hi Team,

The following application note shows there are 100kΩ pull-ups to VIO at RX and TX for Stack Main (Master) Device.
Are these pull-ups mandatory?
We assume stack daisy-chain communication and a host controller is connected to these pins.

https://www.tij.co.jp/jp/lit/an/slua791a/slua791a.pdf

Best Regards,
Yaita

over 4 years ago

+1 Alexander Scheuermann over 4 years ago

TI__Genius 14890 points

Hello Yaita,

Yes, please include these 100k pullup resistors in your design.

0 K.Yaita over 4 years ago in reply to Alexander Scheuermann

Guru 29720 points

Hi Alexander-san,

Thank you for your kind support.
Is it possible to tell me the risk if there are no pullups?

Best Regards,
Yaita

+1 Alexander Scheuermann over 4 years ago in reply to K.Yaita

TI__Genius 14890 points

Yaita-san,

There may be communication errors or loss of communication to the BQ76PL455A-Q1 device. You can find more information in the datasheet section 8.1.2 Communication Buses.

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BQ76PL455A-Q1: Are 100kΩ pull-ups to VIO at RX and TX mandatory?