As we want to check the maximum power consumption for the device, we want to check the current consumption for PCA9306. But only continuous channel current is mentioned in the datasheet(128mA). And which power is responsible for the device, Vref1 or Vref2 ?
Thank you
The current consumption from the supply can be calculated below:
Essentially, you will find the supply current is (Vcc2-Vcc1)/200k ohms.
The voltage across this FET is simply the threshold voltage at about 0.7V.
The power across the channels maximum will be the IoL (current when pulling low) multipled by the Ron between side 1 and side 2 for SDA/SCL. Ron is typically low though you could use 20 ohms as a maximum value for worst case. Current through the channels will be worst when pulling low on side 1 as side 2's current through the device will be larger. This current can be estimated by taking Vref2/R_pullupside2.
Thanks,
-Bobby
