MP6536 current sense resistors

Motor Drivers/Sensors
1

Hi, i have a question about the connections of LS1, LS2 and LS3. In the evaluation board you connected to each pin a shunt resistor and then you filter and amplify the voltage: in this way there are 3 different values, one for each phase. In my application i have space constraint very hard to meet and i can’t use 3 OpAmps. I was wondering if it was possible to short LS1, LS2 and LS3 and use just one shunt resistor and OpAmp in order to read the current.
One more question: is there a minimum value for shunt resistor or 100 mOhm is already the minimum?

Thank you in advance,
regards

2

It isn’t clear from the datasheet that you need these at all. This chip is relatively dumb, the phase just does what it is told by the corresponding PWM input. The 6536 doesn’t need the information provided by the amplified current sense resistor to do its job. Now the question is does the chip driving the 6536 need to see that amplified current in order for it to do its job?
The save your life current limit appears to be internal.