Semiconductor device with combined power and ground ring structure
A semiconductor device includes a lead frame, and an integrated circuit die. The lead frame has a flag for supporting the die and leads that surround that flag and die. The lead frame also has ground ring that surrounds the flag and die. First bond wires electrically connect the die to the lead frame leads. An insulating layer is disposed on the ground ring, and a power layer is disposed on the insulating layer. The semiconductor device further includes second bond wires that connect the die to the ground ring and third bond wires that connect the die to the power layer.
1. A semiconductor device, comprising:
a lead frame having an interior region, a plurality of leads that surround the interior region, and a first ground ring that surrounds the interior region, wherein the first ground ring is generally rectangular and has four sides;
an integrated circuit die having a plurality of die bonding pads on an active surface thereof, wherein the die is located at the interior region of the lead frame;
first bond wires that electrically connect first ones of the die bonding pads with first ones of the lead frame leads;
an insulating layer disposed on the first ground ring, wherein the insulating layer lies on top of and extends over the lengths of the four sides of the first ground ring;
a power layer disposed on the insulating layer;
second bond wires between second ones of the die bonding pads and the power layer;
third bond wires between third ones of the die bonding pads and the ground ring; and
fourth bond wires between the power layer and second ones of the lead frame leads.
2. The semiconductor device of claim 1 , further comprising one or more electrical couplings between the first ground ring and one or more of the die pads.
3. The semiconductor device of claim 1 , wherein the insulating layer is formed of a polyimide tape.
4. The semiconductor device of claim 3 , wherein the power layer comprises a copper trace formed on the polyimide tape.
5. The semiconductor device of claim 1 , wherein the insulating layer and the power layer cover an outermost portion of the first ground ring, and the third bond wires extend from the third ones of the die bonding pads to an inner portion of the first ground ring.
6. The semiconductor device of claim 1 , wherein the lead frame is a quad flat package (QFP) lead frame.
7. The semiconductor device of claim 1 , wherein the interior region of the lead frame includes a flag and the die is mounted on the flag.
8. The semiconductor device of claim 1 , further comprising a second ground ring, wherein the first ground ring is a dummy ground ring.
9. The semiconductor device of claim 8 , further comprising one or more electrical couplings between the second ground ring and one or more of the die pads.
10. The semiconductor device of claim 1 , further comprising a mold compound that at least partially covers the die, the first, second, third and fourth bond wires, the ground ring, and inner portions of the leads.