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Calculating the input current drawn by a MOSFET driver

I am using a PIC32MZ's OC pins (PWM mode, fault disabled) as input to a dual MOSFET driver (ISL89163 A). I need one OC pin to drive 3 drivers i.e 6 inputs each. The pulse width would be around 100~150ns with a repetition frequency around 50~100Hz. The PIC's datasheet ( http://ww1.microchip.com/downloads/en/DeviceDoc/60001191E.pdf page 565) says each I/O pin should be able to source/sink 25mA. I found quiescent current graphs on the driver's datasheet but I am not sure how much its input pins would need. How do I calculate the input current needed by the driver and make sure the PIC pins would be able to source it? Using separate OC pins for each driver is not an option since I am doing something similar on the remaining OC pins too. Also, it's a requirement that each of the 6 inputs shown below are roughly the same, so I do not want to go into synchronizing the OC outputs if I use separate OC pins. I am using FDD8447L for the MOSFET. Here's what my circuit roughly looks like now:

schematic

simulate this circuit – Schematic created using CircuitLab

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