Semiconductor module for a switched-mode power supply and method for its assembly

A method for assembling a semiconductor module for a Switched-Mode Power Supply, comprising:

• providing a semiconductor power switch having a gate electrode, a source electrode and a drain electrode;
• providing a control semiconductor chip;
• providing a leadframe, the leadframe including a die pad and a plurality of leads disposed on one side of the die pad, each lead having an inner portion and an outer portion, wherein the die pad comprises first and second mechanically isolated regions, wherein the leads include a drain lead extending from the first region of the die pad, a ground lead extending from the second region of the die pad, and the remaining leads are spaced at a distance from the die pad such that the remaining leads are not mechanically connected to the die pad;
• mounting the semiconductor power switch on the first region of the die pad;
• mounting the control semiconductor chip on the second region of the die pad;
• forming at least one first bond wire connection between the control semiconductor chip and the gate electrode of the semiconductor power switch;
• forming a plurality of second bond wires extending between the power semiconductor chip and at least one lead and extending between the control semiconductor chip and at least one lead, and
• encapsulating the control semiconductor chip, the semiconductor power switch, the bond wires and the inner portions of the leads in a plastic housing material by a transfer molding process, wherein the plastic housing material electrically isolates the first region and the second region of the die pad and electrically isolates the semiconductor power switch from the control semiconductor chip, and wherein the plastic housing material forms the package housing.