Power amplifier assembly
View Patent ↗The power amplifier module comprises a laminate substrate comprising thermal vias and terminals, as well as a platform device with an interconnection substrate of a semiconductor material. This substrate is provided with electrical interconnects at a first side, and having been mounted on the laminate substrate with an opposite second side. Electrically conducting connections extend from the first to the second side through the substrate. A power amplifier device is attached to the second side of the substrate. One of the electrically conducting connection through the interconnection substrate is a grounding path for the power amplifier, while a thermal path is provided by the semiconductor material. There is an optimum thickness for the interconnection substrate, at which both a proper grounding and a acceptable thermal dissipation is effected.
1. A power amplifier assembly comprising:
a platform device provided with a first and a second side, which comprises an interconnection substrate of semiconductor material and is suitable for mounting on a carrier with its second side, a first electrically conducting connection extending from the first to the second side of the device through the interconnection substrate,
a power amplifier device attached to the first side of the platform device and comprising a first power amplifier;
wherein
the first electrically conducting connection through the interconnection substrate is a grounding path for the first power amplifier, while a thermal path is provided by the semiconductor material of the substrate.
2. A power amplifier assembly as claimed in claim 1 , wherein the interconnection substrate has a thickness enabling that the first connection has a resistance of at most 30 mΩ.
3. A power amplifier assembly as claimed in claim 1 , wherein the interconnection substrate has a heat capacity of at least 0.5 mJ/K.
4. A power amplifier assembly as claimed in any of the previous claims, wherein the thickness of the interconnection substrate is in the range of 0.12-0.28 mm.
5. A power amplifier assembly as claimed in claim 1 , wherein the first power amplifier has a first and a second stage, both of which are provided with an individual grounding path.
6. A power amplifier assembly as claimed in claim 1 , wherein the individual ground paths of the amplifier are coupled electrically on the second side of the platform device.
7. A power amplifier assembly as claimed in claim 1 , wherein the carrier is part of the assembly and comprises contact pads for coupling the assembly to an external carrier or component, while electrical connections extending from the carrier to the platform device.
8. A power amplifier assembly as claimed in claim 7 , wherein said electrical connections comprise signal connections extending from the carrier to the first side of the platform device.
9. A power amplifier assembly as claimed in claim 7 , wherein the carrier is a laminate substrate.
10. A power amplifier assembly as claimed in claim 1 , wherein the power amplifier device is attached to the platform device with a flip-chip assembly technique.
11. A power amplifier assembly as claimed in claim 1 , wherein the platform device comprises at least one interconnect on the first side to connect an output of the power amplifier device to an input of a further device present in the interconnection substrate or assembled thereto.
12. A power amplifier device assembly as claimed in claim 1 , wherein the platform device further comprises passive components that are part of one or more matching circuits.