Is it correct to assume that, in a synchronous rectifying DC/DC converter IC, when the high side transistor is an Nch MOSFET as opposed to Pch MOSFET, the maximum output voltage for a given input is lower but Ron is smaller, so that less heat is generated by the MOSFET itself?|FAQ|ROHM Semiconductor

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Is it correct to assume that, in a synchronous rectifying DC/DC converter IC, when the high side transistor is an Nch MOSFET as opposed to Pch MOSFET, the maximum output voltage for a given input is lower but Ron is smaller, so that less heat is generated by the MOSFET itself?
- In the case of an Nch MOSFET, operation at a 100% duty cycle is not possible, so that the maximum voltage that can be output is lower than for Pch MOSFET, and there is the possibility that the difference between input and output voltages may be large. If the MOSFET sizes are the same, it is reasonable to suppose that the Nch MOSFET, with its smaller Ron, will generate less heat; but it is necessary to consider whether other conditions are equivalent.