rdson
Hello, as far as I know, the power mosfet works in the triode region ,not the saturature region. Yes , we can acquire rdson from the spec which contains the
bonding wire resistance.so when designing the power mosfet size, we need know
how much the bonding wire resistance is. For another aspect, we should consider the Power dissipation in the Power MOSFET, and calculate how many rising temperture from the ambient temperature.
Maybe you can know the inoformation about the bonding wire from the chip's package information. So you can estimate
the length of the bonding wire.Also you can know the maximum load current,
you can estimate bonding wire's diameter. For large load current, it maybe more
than one bonding wire for one PIN to PADS.Sometimes, it could not be known how many bonding wire for the PIN, we can seek help to the X-Ray equipments.
Now you know the bonding wires' length and diameter, you can estimate the resistance of the bonding wire.
Added after 12 minutes:
PS: Generally,for the bonding wire diameter 1mil , the maximum current is 1A
The following is how to calculate the resistance of bonding wire.