A power module has upper and lower transistor dies carried by a lead frame assembly. The assembly has a positive DC paddle for the upper die and an AC paddle for the lower die. An upper plate interconnects a second side of the upper die with the AC paddle, and a lower plate interconnects a second side of the lower die with a negative power bar. Current flowing via positive and negative power bars defines a power loop creating a main magnetic flux with a first direction in a central region and a return direction outside the central region. The upper and lower plates have outer edges having respective notches to concentrate respective portions of a return magnetic flux. Each die has a gate pad connected in a gate loop, wherein the gate loops each overlap a respective concentrated return flux thereby enhancing a common source inductance for each transistor.