The power dissipation of the MAX16814 comes from two sources:
1. The current consumption of the IC itself (VIN x ICC) where ICC is the MAX16814 quiescent current consumption typically 2.5mA
2. The current required to drive the external MOSFET; (VIN – 5V) x (Qg x fsw)
where VIN is the voltage at the IN pin of the IC, Qg is the total gate charge of the chosen MOSFET at 5V, and fsw is the switching frequency.
The total power dissipation of the MAX16814 can be estimated using the following equation:
Ptotal = VIN x ICC + (VIN – 5) x (Qg x fsw)