How to drive the high-side of the bridge in STSPIN32F0?

[adromo95]

Hi all,

I am new to motor control, and I am currently working with the BLDC motor driver board STEVAL-SPIN3201 (based on the STSPIN32F0). I am trying to generate the corresponding PWM signals to drive a BLDC motor. Although the low side of the bridge is working, whenever I try to drive the high-side MOSFETs I get a voltage of around 40 mV in the midpoint between the high and low side of the bridge (e.g., OUTU). When looking at the signal through a oscilloscope I get the attached outcome. Does anybody know what the issue could be? Am I missing something in the control logic driver to enable the OPAMPS?

Also, when I disable both output compare signals (OC1E, OC1NE), I get a voltage in OUTU of around 11 V (supply is 24 Vdc). Is this correct?

Hope that everything is clear.

 

[adromo95]

[SOLVED]

Complementary outputs were not enabled so bootstrap capacitor was not charged. Thus, the high side of the bridge could never be driven.

11V corresponded to the floating voltage (between the phase and ground) when MOSFET was not driven.

I hope it helps to anyone starting to work with BLDC motors and the STEVAL-SPIN3201 :grinning_face_with_sweat: