BLDC PWM Configuration with DRV8301 High side FET switching vs Low and High side switching

Hi Jeff,

I believe if the high-side and low-side MOSFETs are equivalent it is generally considered that the loses are equivalent between high-side vs. low-side switching.

Jeff,

Or are asking about whether you should switch the MOSFETs in complementary mode or non-complementary mode?

We also call this asynchronous vs. synchronous switching. The difference is whether the body diode or MOSFET is carrying the current in the "off" period. It is preferred for the MOSFET (synchronous switching) to be utilized since the MOSFET Rds(on) is generally lower than the resistance of the body diode. This will help with thermal performance, efficiency, and current ripple.

Yes, async vs sync. Makes sense with the Fet Rds(on) at .002

We are trying not to use any extra heat sinking in our application. Also trying to research best practices for tuning the motor to run the most efficient for battery/solar power reasons. Any information here would be great.

Looked like it allowed the FETs to run cooler here but maybe he has something else wrong.

www.avrfreaks.net/.../mosfet-heating-too-much-3phase-bldc-motor-board