AUX_L Mosfet unnecessary?

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1

After being very impressed by the performance of my Odrives i am currently implementing a similar servo driver, though based on the STM32H750 Mcu and TMC6200 gate driver.
One thing just keeps puzzeling me about your design. Whats the use for the Low side Mosfet for the brake resistor. As i understand the brake resistors function is to connect Vbus to GND in a pwm modulated fashion preventing voltage spikes. Whats the benefit of connecting both sides of the resistor to GND during the off_time?

Lastly what do you think about the TMC6200 gate-driver. Reasonably cheap and supports 3-phase inline current sensing?

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There’s no real reason for the half-bridge on the Brake resistor. If I remember correctly, it was designed to be able to drive a brush DC motor or something like that.

Technically it’s safer as we should be able to detect more faults but that’s not even in place at the moment.

@madcowswe will have to answer about the Trinamic driver.