Power amplifier

• US 7,961,470 B2
• Filed: 07/19/2006
• Issued: 06/14/2011
• Est. Priority Date: 07/19/2006
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Fowlkes, Donald, Hoyer, Henrik, Griswold, Bradley
• Primary Examiner(s): Chen; Xiaoliang
• Application Number:
  US11/458,548
• Publication Number:
  US 20080019108A1
• Time in Patent Office: 1,791 Days
• Field of Search: 361/709, 361/704, 361/717, 361/719, 361/721, 361/760, 330/67, 330/302, 257/584, 257/666, 257/675, 257/676, 257/684, 257/691, 257/692, 257/712, 257/723, 257/732, 438/15, 438/122, 438/123, 298/27, 298/47
• US Class Current: 361/709
• CPC Class Codes: H01L 2223/6644 Packaging aspects of high-frequency amplifiers amplifiers per se H03F
• CPC Class Codes: H01L 23/3675 characterised by the shape of the housing
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: Y10T 29/49121 Beam lead frame or beam lead device
• CPC Class Codes: Y10T 29/49156 with selective destruction of conductive paths

Abstract

An RF power amplifier including a single piece heat sink and an RF power transistor die mounted directly onto the heat sink.

Claims

1. A power amplifier, comprising:

a single piece heat sink including a raised pedestal having an attachment surface;

a frame arrangement attached to an outer region of the attachment surface of the raised pedestal;

a power transistor die directly attached to an inner region of the attachment surface of the raised pedestal, the inner region being spaced inward from the outer region;

an electrically conductive lead mounted on a top side of the frame arrangement and extending laterally outward from the frame arrangement away from the raised pedestal so that a gap is formed between the heat sink and a bottom side of the lead;

a printed circuit board attached to the heat sink and at least partly disposed in the gap between the lead and the heat sink; and

an electrical connection between the printed circuit board and the power transistor die via the lead.

2. The power amplifier of claim 1, wherein the frame arrangement includes a dielectric frame and conductive input and output transmission leads attached to the dielectric frame.

3. The power amplifier of claim 1, wherein the power transistor die is enclosed by the frame arrangement on the raised pedestal.

4. The power amplifier of claim 2, wherein the frame arrangement is sized to accommodate the raised pedestal.

5. The power amplifier of claim 4, wherein the raised pedestal has a height that accommodates one or more electrical connections between the input and output leads and the printed circuit board.

6. The power amplifier of claim 5, wherein an opening between the input or output leads and the heat sink is approximately the same as a height of the printed circuit board.

7. The power amplifier of claim 2, comprising one or more capacitors that are attached to the heat sink and that are electrically coupled to the input or output leads.

8. An RF power amplifier, comprising:

a single piece heat sink including a raised pedestal;

a frame arrangement attached to the raised pedestal;

an RF power transistor die directly attached to the raised pedestal so that the frame arrangement encloses the RF power transistor die on the raised pedestal;

an electrically conductive lead mounted on a top side of the frame arrangement and extending laterally outward from the frame arrangement away from the raised pedestal so that a gap is formed between the heat sink and a bottom side of the lead;

a printed circuit board attached to the heat sink and at least partly disposed in the gap between the lead and the heat sink; and

an electrical connection between the printed circuit board and the power transistor die via the lead.

9. The RF power amplifier of claim 8, wherein the frame arrangement includes a dielectric frame and conductive input and output transmission leads attached to the dielectric frame.

10. The RF power amplifier of claim 9, comprising a lid placed on top of the frame arrangement.

11. The RF power amplifier of claim 9, wherein the printed circuit board is configured to electrically connect with the input and output transmission leads.

12. The RF power amplifier of claim 11, wherein an opening between the input or output transmission leads and the heat sink is approximately the same as a height of the printed circuit board.

13. The RF power amplifier of claim 12, wherein the dielectric frame comprises a ceramic material.

14. A power amplifier, comprising:

a single piece heat sink including a raised pedestal;

a frame arrangement that includes input or output leads mounted on a top side of the frame arrangement and which extend laterally outward from the frame arrangement away from the raised pedestal so that a gap is formed between the heat sink and a bottom side of each lead, the frame arrangement attached to the raised pedestal;

a power transistor die directly attached to the raised pedestal so that the power transistor die is thermally and electrically connected to the heat sink and the frame arrangement encloses the power transistor die on the raised pedestal;

a printed circuit board attached to the heat sink and at least partly disposed in the gap; and

one or more electrical connections between the printed circuit board and the input or output leads.

15. A system comprising:

a printed circuit board;

a single piece heat sink attached to the printed circuit board, the single piece heat sink including a raised pedestal;

a frame arrangement attached to the raised pedestal;

an electrically conductive lead mounted on a top side of the frame arrangement and extending laterally outward from the frame arrangement away from the raised pedestal so that a gap is formed between the heat sink and a bottom side of the lead, the printed circuit board being at least partly disposed in the gap; and

a transistor die directly attached to the raised pedestal such that the frame arrangement encloses the transistor die on the raised pedestal.