CN-112468093-B - Compact three-way doherty amplifier module

CN112468093BCN 112468093 BCN112468093 BCN 112468093BCN-112468093-B

Abstract

Embodiments of a method and apparatus are disclosed. In an embodiment, a doherty amplifier module comprises a substrate comprising a mounting surface and further comprising a first amplifier die, a second amplifier die and a third amplifier die on the mounting surface. The first amplifier die is configured to amplify a first Radio Frequency (RF) signal along a first signal path, the second amplifier die is configured to amplify a second RF signal along a second signal path, and the third amplifier die is configured to amplify a third RF signal along a third signal path. The side of the first amplifier die that includes the first output terminal faces the side of the second amplifier die that includes the second output terminal. The second signal path is parallel to the first signal path and the third signal path is orthogonal to the first signal path and the second signal path.

Inventors

WANG LV
Yili A. Maluff
JOSEPH STAUDINGER
Jeffrey kevin jones

Assignees

恩智浦美国有限公司
恩智浦美国有限公司

Dates

Publication Date: 20260421
Application Date: 20200827
Priority Date: 20190906

Claims (8)

1. A doherty amplifier module comprising a first amplifier circuit, characterized by comprising the following steps: A substrate comprising a mounting surface; A first amplifier die on the mounting surface, the first amplifier die including a first input proximate a first side of the first amplifier die and a first output proximate a second side of the first amplifier die, the first amplifier die configured to amplify a first Radio Frequency (RF) signal along a first signal path to generate a first amplified RF signal at the first output, the first signal path extending from the first side of the first amplifier die to the second side of the first amplifier die; A second amplifier die on the mounting surface, the second amplifier die comprising a second input proximate to a first side of the second amplifier die and a second output proximate to a second side of the second amplifier die, the second amplifier die configured to amplify a second RF signal along a second signal path to produce a second amplified RF signal at the second output, the second signal path extending from the first side of the second amplifier die to the second side of the second amplifier die, wherein the second side of the second amplifier die faces the second side of the first amplifier die, and wherein the second signal path is parallel to the first signal path; A third amplifier die on the mounting surface, the third amplifier die including a third input proximate to a first side of the third amplifier die and a third output proximate to a second side of the third amplifier die, the third amplifier die configured to amplify a third RF signal along a third signal path to produce a third amplified RF signal at the third output, the third signal path extending from the first side of the third amplifier die to the second side of the third amplifier die, wherein the third signal path is orthogonal to the first signal path and the second signal path, The doherty amplifier module further comprises: A signal combiner device external to the first, second, and third amplifier dies, wherein the signal combiner device is located on the mounting surface between the first and second amplifier dies, the signal combiner device comprising a first combining node, wherein the first combining node is configured to combine the first amplified RF signal with at least one of the second and third amplified RF signals to produce an amplified RF output signal, Wherein the first combining node comprises a first bond pad on the signal combiner device, the doherty amplifier module further comprising: a first wire bond array coupled between the first output of the first amplifier die and the first bond pad; A second wire bond array coupled between the second output of the second amplifier die and the first bond pad, wherein the first wire bond array and the second wire bond array are parallel to each other, and A third wire bond array coupled between the second output of the second amplifier die and a third output of the third amplifier die, wherein the third wire bond array is orthogonal to the first and second wire bond arrays.
2. The doherty amplifier module of claim 1 wherein: The signal combiner means additionally comprises A first parallel capacitor coupled to the first bond pad, and The doherty amplifier module additionally includes a fourth wire bond array coupled between the first bond pad and the conductive contact on the mounting surface, wherein the fourth wire bond array is orthogonal to the first wire bond array and the second wire bond array, and wherein the first parallel capacitor is configured to perform an impedance transformation to match an impedance of a load to a source impedance.
3. The doherty amplifier module of claim 1 wherein: The signal combiner apparatus additionally includes a second bond pad and a parallel Direct Current (DC) blocking capacitor coupled to the second bond pad, and The doherty amplifier module additionally includes a fourth wire bond array coupled between the first output of the first amplifier die and the second bond pad, wherein the fourth wire bond array is substantially parallel to the first wire bond array.
4. The doherty amplifier module of claim 1 wherein the signal combiner means further comprises: a first parallel capacitor coupled to the first combining node.
5. The doherty amplifier module of claim 4 wherein the first amplifier die comprises a first power transistor and the second amplifier die comprises a second power transistor, wherein a drain-source capacitance of the first power transistor, an inductance of the first wire bond array, and a capacitance of the first parallel capacitor form a first quasi-transmission line configured to perform a first phase delay and a first impedance transformation for the first amplified RF signal, and wherein a drain-source capacitance of the second power transistor, an inductance of the second wire bond array, and the capacitance of the first parallel capacitor form a second quasi-transmission line configured to perform a second phase delay and a second impedance transformation for at least one of the second amplified RF signal or the third amplified RF signal.
6. The doherty amplifier module of claim 5 wherein the third amplifier die comprises a third power transistor, wherein a drain-source capacitance of the third power transistor, an inductance of the third wire bond array, and the drain-source capacitance of the second power transistor form a third quasi-transmission line configured to perform a third phase delay and a third impedance transformation for the third amplified RF signal.
7. A doherty amplifier module comprising a first amplifier circuit, characterized by comprising the following steps: A substrate comprising a mounting surface; A carrier amplifier die on the mounting surface, the carrier amplifier die including a first input proximate a first side of the carrier amplifier die and a first output proximate a second side of the carrier amplifier die; A first peak amplifier die on the mounting surface, the first peak amplifier die including a second input proximate a first side of the first peak amplifier die and a second output proximate a second side of the first peak amplifier die, wherein the second side of the first peak amplifier die faces the second side of the carrier amplifier die; a signal combiner device on the mounting surface, the signal combiner device comprising a first combining node, wherein the signal combiner device is located between the carrier amplifier die and the first peak amplifier die, the first output of the carrier amplifier die being coupled to the first combining node with a first wire bond array, the second output of the first peak amplifier die being coupled to the first combining node with a second wire bond array, wherein the first wire bond array and the second wire bond array are parallel to each other, and A second peak amplifier die on the mounting surface, the second peak amplifier die including a third input proximate a first side of the second peak amplifier die and a third output proximate a second side of the second peak amplifier die, the second side of the second peak amplifier die being orthogonal to the second side of the first peak amplifier die, the third output of the second peak amplifier die being coupled to the second output of the first peak amplifier die with a third wire bond array, wherein the third wire bond array is orthogonal to the first wire bond array and the second wire bond array.
8. A method of manufacturing a doherty amplifier module, the method comprising: Attaching a first amplifier die over a mounting surface of a substrate, the first amplifier die including a first input proximate a first side of the first amplifier die and a first output proximate a second side of the first amplifier die, the first amplifier die configured to amplify a first Radio Frequency (RF) signal along a first signal path to generate a first amplified RF signal at the first output, the first signal path extending from the first side of the first amplifier die to the second side of the first amplifier die; Attaching a second amplifier die over the mounting surface of the substrate, the second amplifier die including a second input proximate to a first side of the second amplifier die and a second output proximate to a second side of the second amplifier die, the second amplifier die configured to amplify a second RF signal along a second signal path to produce a second amplified RF signal at the second output, the second signal path extending from the first side of the second amplifier die to the second side of the second amplifier die, wherein the second side of the second amplifier die faces the second side of the first amplifier die, and wherein the second signal path is parallel to the first signal path, and Attaching a third amplifier die over the mounting surface of the substrate, the third amplifier die including a third input proximate to a first side of the third amplifier die and a third output proximate to a second side of the third amplifier die, the third amplifier die configured to amplify a third RF signal along a third signal path to produce a third amplified RF signal at the third output, the third signal path extending from the first side of the third amplifier die to the second side of the third amplifier die, wherein the third signal path is orthogonal to the first signal path and the second signal path, Wherein the method further comprises attaching a signal combiner arrangement over the mounting surface of the substrate, wherein the signal combiner arrangement is external to the first, second and third amplifier dies, and wherein the signal combiner arrangement is attached over the mounting surface between the first and second amplifier dies, wherein the signal combiner arrangement comprises a first combining node, wherein the first combining node is configured to combine the first amplified RF signal with at least one of the second and third amplified RF signals to produce an amplified RF output signal, And wherein the method additionally comprises coupling a first wire bond array between the first output of the first amplifier die and the first combining node, coupling a second wire bond array between the second output of the second amplifier die and the first combining node, and coupling a third wire bond array between the second output of the second amplifier die and the third output of the third amplifier die, wherein the first and second wire bond arrays are parallel to each other and the third wire bond array is orthogonal to the first and second wire bond arrays.

Description

Compact three-way doherty amplifier module Technical Field The present disclosure relates generally to the field of wireless communications, and more particularly, to a compact three-way doherty amplifier module. Background Wireless communication systems employ power amplifiers to increase the power of Radio Frequency (RF) signals. In a wireless communication system, a power amplifier forms part of the last amplification stage in a transmission chain before providing an amplified signal to an antenna for radiation over an air interface. High gain, high linearity, stability, and high level of power added efficiency are characteristics of the desired amplifier in such wireless communication systems. Typically, the power amplifier operates at maximum power efficiency when the power amplifier is near saturated power emission. However, as the output power decreases, the power efficiency tends to deteriorate. Recently, doherty amplifier architecture has become a focus of not only base stations but also mobile terminals because the architecture has high power added efficiency over a wide power dynamic range. The high efficiency of the doherty architecture makes it the architecture desired for current and next generation wireless systems. However, the architecture presents challenges in semiconductor package design. Current doherty amplifier semiconductor package designs require the use of discrete devices, conductors, and integrated circuits to implement each amplification path. For example, in a three-way doherty architecture comprising a carrier amplification path, a first peak amplification path, and a second peak amplification path, each of the amplification paths may comprise a different power transistor IC die along with different inductive and capacitive components. These different power transistor IC dies and components remain separated by a distance in a typical device package in order to limit potential performance degradation that may occur due to signal coupling between the carrier amplifier, the first peak amplifier, and/or the second peak amplifier. More specifically, undesired signal coupling between the carrier amplifier, the first peak amplifier, and/or the second peak amplifier may involve energy transfer between components of the carrier amplification path, the first peak amplification path, and/or the second peak amplification path by magnetic and/or electric fields associated with signals carried on those amplification paths. Unfortunately, it is desirable to maintain significant spatial distances between amplifier paths in a device package in order to reduce coupling between the paths, limiting the possibilities of miniaturization of the semiconductor package. Limiting miniaturization is undesirable in situations where low cost, low weight, and low volume and small Printed Circuit Board (PCB) footprint are important attributes for a variety of applications. Disclosure of Invention Embodiments of a method and apparatus are disclosed. In an embodiment, a doherty amplifier module includes a substrate including a mounting surface, a first amplifier die on the mounting surface, a second amplifier die on the mounting surface, and a third amplifier die on the mounting surface. The first amplifier die includes a first input proximate to a first side of the first amplifier die and a first output proximate to a second side of the first amplifier die, the first amplifier die configured to amplify a first Radio Frequency (RF) signal along a first signal path to generate a first amplified RF signal at the first output, the first signal path extending from the first side of the first amplifier die to the second side of the first amplifier die. The second amplifier die includes a second input proximate to a first side of the second amplifier die and a second output proximate to a second side of the second amplifier die, the second amplifier die configured to amplify a second RF signal along a second signal path to generate a second amplified RF signal at the second output, the second signal path extending from the first side of the second amplifier die to the second side of the second amplifier die, wherein the second side of the second amplifier die faces the second side of the first amplifier die, and wherein the second signal path is parallel to the first signal path. The third amplifier die includes a third input proximate to a first side of the third amplifier die and a third output proximate to a second side of the third amplifier die, the third amplifier die configured to amplify a third RF signal along a third signal path to generate a third amplified RF signal at the third output, the third signal path extending from the first side of the third amplifier die to the second side of the third amplifier die, wherein the third signal path is orthogonal to the first signal path and the second signal path. In an embodiment, the doherty amplifier module further comprises a signal combiner device external t