I have now got a small clarification of when to read the currents in a 3 phase current sensing method using shunt resistor.
Here all the high legs are ON and hence the low legs are OFF at the center of the ramp. Now for current sensing all the low legs to be ON. So, do we need to sample at the end of the PWM period? Please advise.
But if i see the STM32 user manual
He is sampling at the middle. Please advise.
Yes, it should happen roughly in the middle of the PWM period, when all the complementary PWMs are ON.
That STM document you picked the diagram from explains why they use CH4 to sample a bit before or after the middle.
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Yes understood now thank you.
Probably you were expecting to see something like this
The stm diagram should say ch1n, ch2n and ch3n instead of ch1, ch2 and ch3 to make it clear it’s complementary channels.