DS90UB940-Q1: Resistor selection problem about IDX

Sherry Liang

Part Number: DS90UB940-Q1

Dear team,

My customer chose the address 0x58, but they use R2=10k which doesn't meet the recommendation in the datasheet. What is the bad impacts?

Thanks & Best Regards,

Sherry

0 Hamzeh Jaradat over 5 years ago

Hello Sherry,

it is okay to use 10K ohm here with 1% tolerance.

0 Sherry Liang over 5 years ago in reply to Hamzeh Jaradat

Hi Hamzeh,

If the resistor is smaller than 10k, what will happen?

Thanks & Best Regards,

Sherry

0 Hamzeh Jaradat over 5 years ago in reply to Sherry Liang

Hi Sherry,

the current flow will be higher than wanted.

0 Sherry Liang over 5 years ago in reply to Hamzeh Jaradat

Hi Hamzeh,

Does this cause the I2C address to be incorrect? For example, I set 0x58, but due to smaller resistor, the I2C address is not 0x58.

Thanks & Best Regards,

Sherry

0 Hamzeh Jaradat over 5 years ago in reply to Sherry Liang

I am not sure, but this is possible!

Please follow the d/s instructions to be in the safe side!

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