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PCA9536: Bus expander standby current

Part Number: PCA9536

Hi All,

Can anyone tell me what the typical (or max) standby current is for the PCA9536 with all the I/O set for outputs?  The datasheet only covers the case with the I/O set as inputs.

In my application, the outputs will be set high during standby and will not be sourcing any measurable load current.  They will be within 10mV of my 3.3V Vcc.



  • Hey Kevin,

    "In my application, the outputs will be set high during standby and will not be sourcing any measurable load current."

    -If this is the case, I do not think the typical standby current will really change much by setting the inputs to an output. My reason behind this is that the output stage is accomplished using FETs which are voltage controlled and not current controlled (less wasted current). Most the supply current will be from leakage current through internal FETs. The output node and the input node are both connected to each other so from the device's standpoint the pull up FET (Q1 below) will feed into the input (flip flop). The input is likely a gate which if high, will turn on and generate some small current (leakage) to another FET pulling low.

    My guess here is the supply current will be closer to the 0.2uA that the datasheet states for Vcc = 3.6V as the Vi in this spec is stated to be Vcc which is similar to our case.

    This is under the assumption you do not have a load on the output pins like you've stated in the original post.



  • Thank you Bobby!

    That works for me!!!