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PCA9536: What is P-port status as default?

Part Number: PCA9536

Hello E2E,

What is P-port status  as default?

I saw the description in datasheet that the default is input with high-Z mode in p.16, but i could see the internal pull-high 100k in figure 17.

Which one is correct?

In system requirement, the default P-port needs to be low. could customer put a pull-low resistor on each P-port?

if ok, what is the maximum pull low resistor value?

or

any part is suitable to use in this application.

Sincerely,

Jason 

  • Hi Jason,

    The ports are configured as inputs by default and have a pull-up resistance that is typically 100 kOhm.  To compute the maximum pull-down resistance value you could look at the maximum low-level input current specification (IIL, which is -100 uA) and the maximum low-level input voltage (VIL, which is 0.8 V).  This gives a maximum allowable pull-down resistance of (0.8 V) / (100 uA) = 8 kOhm.

    Please let me know if this is not clear or if you have further questions.

    Regards,
    Max