RF power amplifier and method for packaging the same
View Patent ↗A method and apparatus is provided for use in power amplifiers for reducing the peak voltage that transistors are subjected to. A power amplifier is provided with first and second switching devices and an inductor connected between the switching devices. The switching devices are driven such that the switching devices are turned on and off during the same time intervals.
1. An RF power amplifier suitable for transmitting signals in a mobile telephone system comprising:
a multi-layer chip carrier having a first side adapted to be mounted to a printed circuit board, and a second side;
a complimentary metal-oxide semiconductor (CMOS) device, the CMOS device having a plurality of connection points adapted to be mounted to the second side of the chip carrier, wherein the CMOS device and the chip carrier are packaged together to form the RF power amplifier;
an amplifier having one or more passive elements formed in the chip carrier and one or more switching devices formed in the CMOS device; and
an output matching network having an inductor formed in the multi-layer chip carrier, the inductor having a loop formed along a plane oriented perpendicular to conductive layers of the multi-layer chip carrier.
2. The RF power amplifier of claim 1 , wherein the inductor further comprises:
a first leg formed using a first via extending from a first CMOS device connection point through the multi-layer chip carrier;
a second leg formed using a second via extending from a second CMOS device connection point through the multi-layer chip carrier; and
a third leg electrically coupled between the first and second vias, the third leg being formed using a conductive trace on one layer of the multi-layer chip carrier.
3. The RF power amplifier of claim 1 , wherein the output matching network includes one or more transformers.
4. The RF power amplifier of claim 1 , wherein the output matching network includes an inductive network.
5. The RF power amplifier of claim 4 , wherein the inductive network further comprises a plurality of inductors formed in the multi-layer chip carrier.
6. The RF power amplifier of claim 5 , wherein the plurality of inductors of the inductive network are formed using a plurality of vias extending from respective CMOS device connection points through the multi-layer chip carrier and a plurality of conductive traces formed on one or more layers of the multi-layer chip carrier.
7. An RF power amplifier package suitable for transmitting signals in a mobile telephone system comprising:
a multi-layer chip carrier having a first side, one or more conductive layers, and a second side having a plurality of connection points adapted to be mounted to a circuit board;
a complimentary metal-oxide semiconductor (CMOS) device, the CMOS device having a plurality of connection points adapted to be mounted to the first side of the chip carrier;
a plurality of RF amplifier stages, each RF amplifier stage further comprising one or more passive elements formed in the chip carrier and one or more active devices formed in the CMOS device; and
one or more inductors formed in the multi-layer chip carrier, wherein each of the one or more inductors forms a loop formed along a plane oriented perpendicular to the conductive layers of the multi-layer chip carrier.
8. The RF power amplifier of claim 7 , wherein at least one of the one or more inductors comprises a first via extending into the chip carrier, a second via extending into the chip carrier, and a conductive strip extending between the first and second vias.
9. The RF power amplifier of claim 8 , wherein the first via extends into the chip carrier from the first side of the multi-layer chip carrier at a point corresponding to a first connection point of the CMOS device.
10. The RF power amplifier of claim 9 , wherein the second via extends into the chip carrier from the first side of the multi-layer chip carrier at a point corresponding to a second connection point of the CMOS device.
11. The RF power amplifier of claim 7 , wherein the chip carrier is adapted to be mounted to a printed circuit board by soldering the connection points of the chip carrier to the printed circuit board.
12. The RF power amplifier of claim 7 , wherein the one or more passive elements formed in the chip carrier include a transformer.
13. The RF power amplifier of claim 7 , wherein the one or more active elements formed in the CMOS device include one or more switching devices.
14. The RF power amplifier of claim 7 , wherein the RF power amplifier package is a GSM power amplifier.
15. The RF power amplifier of claim 7 , wherein the multi-layer chip carrier is a ceramic chip carrier.
16. A method of amplifying signals for a mobile telephone system comprising:
providing a chip carrier having an upper surface, one or more conductive layers, and a lower surface;
mounting a complimentary metal-oxide semiconductor (CMOS) device to the upper surface of the chip carrier to form a package;
providing a plurality of RF amplifier stages, wherein each RF amplifier stage is formed using one or more passive elements formed in the chip carrier and one or more active devices formed in the CMOS device;
forming at least one inductor in the chip carrier, the at least one inductor comprising a loop formed on a plane oriented perpendicular to the upper and lower surfaces of the chip carrier;
mounting the lower surface of the chip carrier to a circuit board; and
using the package to amplify signals.
17. The method of claim 16 , wherein forming the at least one inductor in the chip carrier further comprises:
using a first via to form a first leg extending at least partially through the multi-layer chip carrier;
using a second via to form a second leg extending at least partially through the multi-layer chip carrier; and
forming a third leg between the first and second vias using a conductive trace on one layer of the chip carrier.
18. The method of claim 17 , wherein the first leg, second leg, and third legs define the plane that is oriented perpendicular to the upper and lower surfaces of the chip carrier.
19. The method of claim 16 , wherein the one or more passive elements formed in the chip carrier include a transformer.
20. The method of claim 16 , wherein the one or more active elements formed in the CMOS device include switching devices.
21. The method of claim 16 , wherein the chip carrier is a ceramic chip carrier.