Other Parts Discussed in Thread: LM5113
The driver is being used as an independent high and low-side MOSFET driver.
The high side charges 1300uF of capacitive load, and its use is for inrush current limit. That means that HS is connected to the positive terminal of the capacitor and the source terminal of the MOSFET transistor with a shunt resistor measuring the inrush current.
The HI input at the LM5113 driver is connected to the output of a voltage comparator that sees the Vrshunt.
When 0V are @ HS terminal the misfit transistor switches properly, however as the voltage increases the Vgs decrease until the MOSFET goes off. With the comparator enabled the the voltage at HS with the circuit active goes only up to 1.46V as the Vgs threshold of the transistor is 1.6V tap 2.5V max, and HB is measured @ 4.5V, independent of the voltage @ HS.
We have: Changed the 0.1uF bootstrap capacitor to 0.22uF, decreased the 100Ohm bootstrap resistor to 0, also, we removed that resistor so only the internal bootstrap diode would work, the only relatable change is when we shortcircuit R bootstrap, the Voltage @ HS goes up to 1.6V, from 1.4V with the original circuit.