Gain and bandwidth enhancement for RF power amplifier package

• US 6,466,094 B2
• Filed: 01/10/2001
• Issued: 10/15/2002
• Est. Priority Date: 01/10/2001
• Status: Expired due to Term

• Current Assignee: MACOM Technology Solutions Holdings, Inc.
• Original Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Inventors: Leighton, Larry C., Perugupalli, Prasanth
• Primary Examiner(s): Pascal, Robert
• Assistant Examiner(s): NGUYEN, KHANH V
• Application Number:
  US09/758,629
• Publication Number:
  US 20020125955A1
• Time in Patent Office: 643 Days
• Field of Search: 330/277, 330/302, 330/307
• US Class Current: 330/302
• CPC Class Codes: H01L 2223/6644 Packaging aspects of high-frequency amplifiers amplifiers per se H03F
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/49175 Parallel arrangements
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H03F 1/565 using inductive elements

Abstract

Gain and bandwidth enhancement of a RF power amplifier package is effected by electrically coupling a power transistor to a RF signal source with an inductance, and further electrically coupling the input and common element terminals of the power transistor with a shunt inductance. The shunt inductance is chosen such that its reactance is the conjugate of the reactance of the power transistor'"'"'s common-input capacitance. A similar conjugate matching output circuit is provided to electrically couple the transistor'"'"'s output and common element terminals to a load. The shunt inductors are implemented on the package substrate by connecting the respective input and output transistor terminals to grounded shunt caps via bond wires.

Claims

1. A RF power amplifier circuit, comprising;

a transistor having an input terminal, an output terminal and a common element terminal, and further having a common-input capacitance and a common-output capacitance; and

an input circuit configured for receiving a RF signal from a RF signal source and for electrically coupling the RF signal source across the respective input and common element terminals of the transistor, the input circuit comprising a first input inductor for coupling the RF signal source to the input terminal and a second input inductor coupling the input terminal to the common element terminal, the input circuit substantially matching an impedance of the RF signal source to both a resistive component and a capacitive reactance of the transistor input,

wherein the second input inductor is chosen so that its reactance is substantially the conjugate of the reactance of the common-input capacitance.

2. The power amplifier of claim 1, further comprising an output circuit configured for electrically coupling a load across the respective output and common element terminals of the transistor, the output circuit comprising a first output inductor adapted to couple the load to the output terminal and a second output inductor coupling the output terminal to the common element terminal, wherein the second output inductor is chosen so that its reactance is substantially the conjugate of the reactance of the common-output capacitance.

3. The power amplifier of claim 1, wherein the transistor comprises a LDMOS transistor.

4. The power amplifier of claim 1, wherein the transistor comprises a bipolar junction transistor.

5. The power amplifier of claim 1, wherein the second input inductor comprises one or more bond wires.

6. The power amplifier of claim 2, wherein the second output inductor comprises one or more bond wires.

7. The power amplifier of claim 1, wherein the value of the second input inductor is determined by the length and number of bond wires.

8. The power amplifier of claim 2, wherein the value of the second output inductor is determined by the length and number of bond wires.

9. A RF power amplifier package comprising:

a substrate;

a transistor disposed on the substrate, the transistor having an input terminal, an output terminal and a common element terminal, and further having a common-input capacitance and a common-output capacitance;

an input lead;

one or more input bond wires coupling the input lead to the input terminal of the transistor; and

one or more input shunt bond wires coupling the input terminal to the common element terminal, the one or more input shunt bond wires having a reactance that is substantially the conjugate of the reactance of the common-input capacitance.

10. The RF power amplifier package of claim 9, further comprising an input shunt cap disposed on the substrate and connected to a reference ground, wherein the one or more input bond wires couple the input terminal of the transistor to the input shunt cap.

11. The RF power amplifier package of claim 9, further comprising:

an output lead;

one or more output bond wires coupling the output lead to the output terminal of the transistor; and

one or more output shunt bond wires coupling the output terminal to the common element terminal, the one or more output shunt bond wires having a reactance that is substantially the conjugate of the reactance of the common-output capacitance.

12. The RF power amplifier package of claim 11, further comprising an output shunt cap disposed on the substrate and connected to an electrical ground, wherein the one or more output bond wires couple the output terminal of the transistor to the output shunt cap.

13. The RF power amplifier package of claim 9, wherein the transistor comprises a LDMOS transistor.

14. The RF power amplifier package of claim 9, wherein the transistor comprises a bipolar junction transistor.