DocID024230 Rev 1

13/15

AN4250

Fishbone diagram for Power MOSFET in parallel

15

Causes linked to the method

Different torque on heatsink

Different torque of the two devices causes different heat dissipation and the current

unbalance.

Figure 11. Additional Fishbone diagram for parallel configuration

APPLICATION

CURRENT

UNBALANCE

Circuit component

Parasitic

inductances

Gate circuitry

Boost diode

MATERIAL

Difference of intrinsic Power MOSFET

characteristics

Vth differences

Rdson differences

gfs influence

METHOD

Difference torque of the

mounting on heatsink

Temperature

unbalance

difference

AM17359v1