Discrete dual pads for a circuit
Implementations of high-power semiconductor device modules are described, including automotive power transistor assemblies for use in power amplifier circuits such as a cascode circuit. In some implementations, power amplifier circuit components are provided on separate semiconductor die attached to discrete dual die attach pads. A separation between the die attach pads, as well as a through-hole, provide sufficient isolation between the die to permit operation of the circuit at high voltages without relying on a thick multi-layer direct bond copper (DBC) isolation structure. In some implementations, higher voltage operation can be supported by a thin multi-layer, resin coated copper DAP in which the top layer is split.
1 . An apparatus, comprising:
a split lead frame having split lead frame body sections separated by an isolation region, wherein the split lead frame body sections include a first split lead frame body section and a second split lead frame body section;
a die attach pad (DAP) on an upper surface of each of the split lead frame body sections;
an electronic circuit including a first device in a first die coupled to a second device in a second die, the first die and the second die arranged side-by-side on the upper surface, the first die being disposed on the first split lead frame body section and the second die being disposed on the second split lead frame body section;
an insulator in contact with the upper surface and a lower surface of the split lead frame; and
a dummy lead extending from at least one of the split lead frame body sections.
2 . The apparatus of claim 1 , wherein the first die is made of silicon and the second die is made of silicon carbide (SiC).
3 . The apparatus of claim 1 , wherein the insulator is a molding compound disposed within the isolation region.
4 . The apparatus of claim 3 , further comprising a dam bar disposed in each of the split lead frame body sections to block flow of the molding compound.
5 . The apparatus of claim 1 , wherein the isolation region is less than or equal to 2.0 mm wide.
6 . The apparatus of claim 1 , wherein the electronic circuit is configured to operate at a voltage up to about 600 V.
7 . The apparatus of claim 1 , wherein the electronic circuit is a two-stage amplifier.
8 . The apparatus of claim 1 , wherein the electronic circuit is a SiC based cascode circuit.
9 . The apparatus of claim 1 , wherein a first section of the first split lead frame body section and a second section of the second split lead frame body section define a single DAP.
10 . An apparatus, comprising:
a split lead frame body having an upper surface and a lower surface, the split lead frame body being split into a first split lead frame body section and a second split lead frame body section separated by a gap;
an electronic circuit coupled to the upper surface, the electronic circuit including a first device included in a first die coupled to a second device included in a second die, the first die coupled to a die attach pad (DAP) in the first split lead frame body section and the second die coupled to a DAP in the second split lead frame body section;
an insulating layer coupled to the lower surface of the split lead frame body; and
a temperature sensor included in the second die and electrically coupled to a lead.
11 . The apparatus of claim 10 , wherein the insulating layer is a resin coated copper layer.
12 . The apparatus of claim 10 , further comprising a backplane coupled to the insulating layer.
13 . The apparatus of claim 10 , wherein the gap is an isolation region filled with a molding compound.
14 . The apparatus of claim 13 , wherein the isolation region is less than or equal to 2.0 mm wide.
15 . The apparatus of claim 10 , wherein the electronic circuit is an amplifier circuit configured to operate at a high voltage up to about 1700 V.
16 . The apparatus of claim 10 further comprising a dummy lead extending from the second split lead frame body section.
17 . An apparatus, comprising:
a split lead frame including:
a first split lead frame section including a first body section and at least one first lead extending from the first body section;
a second split lead frame section, separated from the first split lead frame section by a gap, including a second body section and at least one second lead extending from the second body section; and
a dummy lead extending from at least one of the first split lead frame section or the second split lead frame section;
a first die attach pad (DAP) on an upper surface of the first body section;
a second DAP on an upper surface of the second body section;
a first die coupled to a surface of the first DAP;
a second die coupled to a surface of the second DAP; and
molding material disposed in the gap and isolating the first body section from the second body section.
18 . The apparatus of claim 17 , wherein the molding material is in contact with an upper surface and a lower surface of the split lead frame.
19 . The apparatus of claim 17 , wherein the gap is at least 1.6 mm.
20 . The apparatus of claim 17 , wherein the dummy lead is coupled to the second DAP.