Break resistor, Shunt regulator, low side mosfet

1

If I understand correctly the AUX connection connects a resistor from ground to DCBus (main power in) through two paralleled mosfet when the voltage rises above the power supply voltage, so that the power created whilst breaking is dissipated through the resistor.

It this is correct then why is are there also 2 parralel mosfet between the AUX+ and GND?

Are these used when there is a break resistor connected?

2

IIRC that was originally so that you could connect a DC motor or some other object that wants a half-bridge design.

3

Ah. Okay thanks. That’s what I thought it was for. Just needed to check before eliminating it from a design.