Hi there, I would really like to try out the MP6543C, however, I only need/want single shunt topology. I am wondering if i tie all the low sides together, if SOA will still reflect the current even if its low side fet is off?
Hello ezra.vanderjagt,
I will have to check on if using a single shunt is alright.
Just to clarify the datasheet states that this will only sense current through the low side FET. It does this in forward and reverse directions.
Ok, I made a little development board and can confirm the following:
- The SOx voltage is only amplified if current is flowing through that specific low side FET. As opposed to my original hunch, which was wondering if SOx is actually some sort of Opamp multiplier that didn’t need current flowing.
- Shorting the SOx pins breaks the chip. My last test I pull them all to ground through the same resistor. No smoke was released, but when I returned the chip to it’s original configuration it can’t output motor signals properly.
The moral of the story is no, MP6543C’s CSA’s cannot work in single shunt mode. Hopefully this information is of use to someone!