Shielded lead frame packages
Devices and methods are disclosed, related to shielding and packaging of radio-frequency (RF) devices on substrates. In some embodiments, A radio-frequency (RF) module comprises a lead-frame package with a plurality of pins and at least one pin exposed from overmold compound. The module further includes a metal-based covering over a portion of the lead-frame package. Additionally, the metal-based covering can be in contact with the at least one pin.
1. A radio-frequency module comprising:
a lead-frame package with a plurality of pins and at least one pin exposed from overmold compound, the lead-frame package including an inner row and an outer row of pins on each side, and all the pins of all the outer rows of pins assigned to ground; and
a metal-based covering over a portion of the lead-frame package, the metal-based covering in contact with the at least one pin.
2. The module of claim 1 wherein the module is mounted to a substrate, and the metal-based covering is connected to a ground plane within the substrate.
3. The module of claim 2 wherein the at least one pin is soldered to a ground connection on the substrate, to connect the metal-based covering to the ground plane.
4. The module of claim 1 wherein the portion of the lead-frame package covered by the metal-based covering includes all but one side of the lead-frame package.
5. The module of claim 1 wherein the metal-based covering includes two or more layers of metal.
6. The module of claim 5 wherein at least one layer of the two or more layers includes a first metallic composition that differs from a second metallic composition of another layer of the two or more layers.
7. The module of claim 1 wherein the lead-frame package includes a semiconductor die and none of the pins of the outer rows of pins are electrically connected to the semiconductor die.
8. The module of claim 1 wherein the metal-based covering is applied by spraying metallic paint on the lead-frame package.
9. A wireless device comprising:
an antenna; and
a module in communication with the antenna, the module configured to provide electro-magnetic interference shielding for a lead-frame package, the module including a lead-frame package having a plurality of pins with at least one pin exposed from overmold compound, the lead-frame package including an inner row and an outer row of pins on each side, and all the pins of all the outer rows of pins assigned to ground, the module further including a metal-based covering over a portion of the package, the metal-based covering in contact with the at least one pin.