Power amplifier system, method for adjusting the gain of a power amplifier stage, and portable device

Abstract

The present invention provides a system and method including a variable power amplifier bias impedance. [Solution] A power amplifier 29 includes a bias circuit 30 that receives a bias voltage Vbias and generates a bias signal, and a power amplifier stage 41 that receives an input radio frequency (RF) signal TFIN and generates an output RF signal, the power amplifier 29 including a bias impedance component 81 operably coupled between the bias circuit and the power amplifier stage. The bias impedance component receives a control signal CTRL and adjusts the impedance value of the bias impedance component in response to the control signal.

Description

Technical Field

[0001] Embodiments of the disclosed technology relate to electronic systems, and more particularly to systems including power amplifiers for radio frequency (RF) electronics devices.

[0002] Cross - Reference to Related Applications This application claims the benefit of U.S. Provisional Application No. 62 / 713,150, filed on Aug. 1, 2018, which is hereby incorporated herein by reference in its entirety.

Background Art

[0003] RF power amplifiers can be used to boost the power of relatively low - power RF signals. The boosted RF signals can then be used for various purposes, including driving the antenna of a transmitter .

[0004] Power amplifiers can be included in mobile phones to amplify RF signals for transmission purposes. For example, in mobile phones that communicate using cellular standards, wireless local area network (WLAN) standards, and / or any other suitable communication standards, power amplifiers can be used to amplify RF signals. Managing the amplification of RF signals is important . If an RF signal is amplified to an incorrect power level or significant distortion is introduced into the original RF signal, the wireless device can cause out - of - band transmissions and non - compliance with authorized standards . Applying bias to a power amplifier device is an important part of managing amplification because it can determine the voltage and / or current operating points of the amplification devices within the power amplifier .

[0005] ​​​​​​​​An improved power amplification system is needed. Furthermore, the bias application of the power amplifier is required. Improving this is also considered necessary. [Overview of the project]

[0006] Several aspects of this disclosure are techniques and methods that can be used to improve the bias application of power amplifiers. This relates to electronic systems. For example, in one aspect, a power amplifier system has a bias voltage A bias circuit configured to generate a bias signal in response to the input radio frequency signal, and a bias circuit configured to generate a bias signal in response to the input radio frequency signal. The system includes a power amplifier stage configured to receive and generate an output radio frequency signal. Furthermore, a bias impedance is operably coupled between the bias circuit and the power amplifier stage. Includes a dance component. The bias impedance component receives the control signal. The impedance of the bias impedance component in response to the said control signal. It is configured to adjust the values.

[0007] According to other aspects of this disclosure, a method for adjusting the gain of a power amplifier stage is provided. The method is: In a bias circuit, receiving a bias voltage and based on that bias voltage, the The bias signal is generated by the IAS circuit, and the bias impedance component The method further includes receiving the bias voltage and control signal at the terminal. In the bias impedance component, the bias impedance component The impedance value is adjusted based on the received control signal, and in the power amplifier stage... , the input radio frequency signal and bias current from the bias impedance component Receiving pressure and outputting a radio frequency based on the input radio frequency signal and bias voltage This includes generating signals.

[0008] According to further aspects of this disclosure, a mobile device is provided. The mobile device is input A power amplifier configured to amplify a radio frequency signal and generate an output radio frequency signal, A modulator configured to generate a radio frequency transmission signal based on the output radio frequency signal. This includes the following. The power amplifier is configured to receive a bias voltage and generate a bias signal. A bias circuit and a configuration for receiving an input radio frequency signal and generating an output radio frequency signal. A power amplifier stage and a bias circuit are operably coupled between the power amplifier stage and the bias circuit. Includes a bias impedance component. The Nent receives a control signal and, in response to the control signal, the bias impedance capacitor It is configured to adjust the impedance value of the component. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram of a power amplifier module that amplifies radio frequency (RF) signals. [Figure 2] This is a schematic block diagram of an example wireless device that may include one or more of the power amplifier modules shown in Figure 1. [Figure 3] This is a schematic block diagram of one example of a power amplifier system. [Figure 4] This is a schematic block diagram of another example of a power amplifier system relating to multiple aspects of this disclosure. [Figure 5A] This is a schematic block diagram of yet another example of a power amplifier system relating to multiple aspects of this disclosure. [Figure 5B] This is a schematic block diagram of yet another example of a power amplifier system relating to multiple aspects of the present disclosure. [Figure 6]Figures 6A-6F are graphs showing the effect of the change of bias impedance on the power amplifier characteristics according to multiple aspects of the present disclosure. [Figure 7] It is a graph showing the gain in the output stage of a power amplifier according to multiple aspects of the present disclosure as a function of the output power. [Figure 8] Figures 8A-8D show a certain number of power amplifier characteristics according to multiple aspects of the present disclosure. [Figure 9] An embodiment of a multi-stage power amplifier system according to multiple aspects of the present disclosure is shown. [Figure 10] It is a schematic block diagram of another example of a power amplifier system according to multiple aspects of the present disclosure. [Figure 11] It is a schematic block diagram of yet another example of a power amplifier system according to multiple aspects of the present disclosure.

Mode for Carrying Out the Invention

[0010] The headings given here, even if any exist, are for convenience only and do not necessarily affect the scope or meaning of the invention according to the claims.

[0011] An apparatus and method for applying a bias to a power amplifier are disclosed herein. In a given implementation example a power amplifier system including a power amplifier and a bias circuit is provided. The power amplifier can be used to amplify a radio frequency (RF) signal for transmission purposes. The bias circuit can be used to generate a bias voltage for applying a bias to the power amplifier. The power amplifier bias circuit can receive an enable signal that can be used to enable or disable the power amplifier and pulse the output of the power amplifier. can be used to receive an enable signal that can be used to enable or disable the power amplifier and pulse the output of the power amplifier. can be.

[0012] As will be described in detail below, the bias circuit biases the signal applied to the power amplifier. Impedance can affect the predetermined characteristics of the power amplifier, particularly the power amplifier gain characteristics. In other words, the design and selection of the bias impedance provided by the bias circuit is These are important design characteristics to consider when designing power amplifier systems. Several aspects of this disclosure are This relates to a power amplifier system that may have an adjustable bias impedance. The power bias impedance is determined according to the design and / or application requirements of the power amplification system. It can be used to select the amplifier gain characteristics.

[0013] Overview of Multiple Examples of Power Amplifier Systems

[0014] Figure 1 is a schematic diagram of a power amplifier module 10 that amplifies radio frequency (RF) signals. Yes. The illustrated power amplifier module (PAM) 10 amplifies the RF signal RF_IN and increases it. It can be configured to generate a wide RF signal RF_OUT. As described here, The power amplifier module 10 may include one or more power amplifiers, such as a multi-stage power amplifier. ru.

[0015] Figure 2 shows an example of a wireless or portable device that may include one or more power amplifier modules as shown in Figure 1. This is a schematic block diagram of 11. The wireless device 11 implements one or more features of the present disclosure. This may include a power amplifier bias circuit.

[0016] The wireless device 11 in this example, as depicted in Figure 2, is a multiband / multimode mobile phone. This may represent a multiband and / or multimode device, such as a machine. In this configuration, the wireless device 11 includes a switch 12, a transceiver 13, an antenna 14, and a power amplifier. 17. Control component 18. Computer-readable medium 19. Processor 20 and battery 2 Includes 1.

[0017] The transceiver 13 can generate an RF signal for transmission via the antenna 14. Furthermore, the transceiver 13 can receive RF signals coming from the antenna 14. .

[0018] As you can understand, the various functions associated with transmitting and receiving RF signals are shown in Figure 2. This is achieved by one or more components, collectively represented as transceiver 13. It is possible to give a single component both sending and receiving functions. It can be configured. In other examples, the transmission and reception functions can be handled by separate components. You can also give it to them.

[0019] Similarly, as should be understood, various antennas associated with the transmission and reception of RF signals The functions are represented collectively as transceiver 14 in Figure 2, and are one or more components. This can be achieved by using a single antenna that performs both transmitting and receiving functions. It can be configured to provide the necessary functions. In other examples, the transmitting and receiving functions are provided by separate antennas. It can also be given by. In further other examples, associated with wireless device 11 Different antennas are assigned to different frequency bands.

[0020] In Figure 2, one or more output signals from the transceiver 13 are transmitted through one or more transmission paths 15. It is drawn so that it is supplied to antenna 14 via. In the example shown, different transmission paths 15 may represent output paths associated with different bandwidths and / or different power outputs. Example For example, the two power amplifiers 17 shown in the examples have different power output configurations (e.g., low power output and Amplification associated with high power output, and / or amplification associated with different bandwidths. It is possible. Although Figure 2 shows a configuration using two transmission paths 15, wireless devices S11 can be adapted to include more or fewer transmission paths 15. .

[0021] The power amplifier 17 can be used to amplify a wide variety of RF signals. For example, One or more of the power amplifiers 17 pulse the output of the power amplifiers to create a wireless local area To assist in transmitting network (WLAN) signals or any other suitable pulsed signals. A valid signal that can be used as much as possible may be received. In a predetermined configuration, a power amplifier One or more of the 17 are configured to amplify the Wi-Fi signal. Each of the power amplifiers 17 Therefore, it is not necessary to amplify the same type of signal. For example, one power amplifier can amplify a WLAN signal. While it can amplify the signal, other power amplifiers, such as GSM (Registered Trademark) (Global S), can amplify the signal. CDMA (code division m) signal for mobile systems Ultimate access) signal, W-CDMA signal, Long-Term Evolution It can amplify LTE signals or EDGE signals.

[0022] One or more features of this disclosure may be applied to the modes and / or bandwidths of the examples described above, and to other communication standards. It can be implemented in [location / platform].

[0023] In Figure 2, one or more detection signals from antenna 14 are transmitted through one or more receiving paths 16. It is drawn so as to be given to the transceiver 13 via. In the example shown, different receiving paths 16 may represent paths associated with different frequency bands. Figure 2 shows four receiving paths 16. Despite the configuration used, the wireless device 11 receives more or less than that amount. It can be adapted to include route 16.

[0024] To facilitate switching between the receiving and transmitting paths, switch 12 was selected. The antenna 14 can be configured to be electrically connected to the transmission path or reception path. In other words, the switch 12 controls a certain number of switches associated with the operation of the wireless device 11. A switching function can be provided. In a predetermined configuration, the switch 12 can, for example, different Switching between different bandwidths, switching between different power modes, transmit modes and receive modes A function that provides switching between or any combination thereof. It may include constant switches. Switch 12 also filters and / or durates signals. Additional functions, including plexing, can also be provided.

[0025] Figure 2 shows a predetermined configuration comprising a switch 12, a power amplifier 17, and / or a bias. Controls various control functions associated with the operation of other operating components, such as circuits. This demonstrates that a control component 18 can be provided. Control component 1 Eight non-restrictive examples are detailed here.

[0026] In a given configuration, the processor 20 is configured to implement the various processes described herein. It can be configured to simplify the process. The processor 20 processes computer program instructions. These computer program instructions can be used to operate. It can be assigned to 0.

[0027] In a given configuration, such computer program instructions are also computer-readable. Stored in memory 19, and specific to the processor 20 or other programmable data processing device. It can be operated in a specific manner.

[0028] Battery 21 may be any suitable battery used in the wireless device 11, for example This includes lithium-ion batteries.

[0029] Figure 3 is a schematic block diagram of one example of a power amplifier system 26. The power amplifier system 26 includes a switch 12, an antenna 14, a battery 21, and a directional coupler 24. The diagram shows the power amplifier bias circuit 30, the power amplifier 32 and the transceiver 33. The receiver 33 includes a baseband processor 34, an I / Q modulator 37, a mixer 38, and an analog Includes a digital-to-analog converter (ADC) 39. Although not shown in Figure 3 for clarity, Furthermore, the transceiver 33 is associated with receiving signals via one or more receiving paths. It may include a circuit.

[0030] The baseband signal processor 34 generates a sine wave or sine signal of desired amplitude, frequency, and phase. It can be used to generate I and Q signals that can be used to represent, for example, The I signal is used to represent the in-phase component of the sine wave, and the Q signal is used to represent the orthogonal component of the sine wave. These are used. These can be equivalent representations of sine waves. In a given implementation example, The I and Q signals are supplied to the I / Q modulator 37 in digital format. The bandwidth processor 34 is configured to process any appropriate processor for the base bandwidth signal. It may be considered as such. For example, the baseband processor 34 is a digital signal processor, microphone It may include a processor, a programmable core, or any combination thereof. In some implementations, the power amplifier system 26 has two or more baseband processors. It can include sessa 34.

[0031] The I / Q modulator 37 receives the I signal and Q signal from the baseband processor 34, The system can be configured to process the I signal and Q signal to generate an RF signal. For example, The I / Q modulator 37 is configured to convert the I signal and Q signal into an analog format. A DAC, a mixer that upconverts the I and Q signals to radio frequencies, and an upconverter The converted I and Q signals are coupled to determine an appropriate R for amplification by the power amplifier 32. It may include a signal coupler that converts to an F signal. In a given implementation example, the I / Q modulator 37 is One or more filters configured to filter the frequency content of the signal being processed It may include.

[0032] The power amplifier bias circuit 30 receives the ENABLE signal from the baseband processor 34. Furthermore, a battery or high power voltage VCC can be received from battery 21, and the active signal ENABL E is used to provide the bias voltage V for the power amplifier 32. BIAS It can generate [this].

[0033] Figure 3 shows the power high voltage V CC Despite showing a battery 21 that directly generates a predetermined actual In the example, the power high voltage V CC The regulator is powered using battery 21. This can be the adjusted voltage that is generated. For example, the power high voltage V CC To generate Using a switching regulator such as a buck and / or boost converter It is possible.

[0034] The power amplifier 32 receives the RF signal from the I / Q modulator 37 of the transceiver 33 and amplifies it. The RF signal can be supplied to the antenna 14 via the switch 12.

[0035] The directional coupler 24 is positioned between the output of the power amplifier 32 and the input of the switch 12. Therefore, the output power of the power amplifier 32 does not include the insertion loss of switch 12. Force measurement is permitted. The sensed output signal from the directional coupler 24 is sent to the mixer 38. The mixer 38 multiplies the sensed output signal by a reference signal of a controlled frequency. It can be shifted. This allows the frequency content of the sensed output signal to be downshifted. This allows a downshift signal to be generated. The downshift signal is supplied to the ADC39. The ADC39 provides a downshift signal suitable for processing by the baseband processor 34. It can be converted to a digital format.

[0036] A feedback path is included between the output of the power amplifier 32 and the baseband processor 34. As a result, the baseband processor 34 dynamically adjusts the I and Q signals to amplify power. The device system 26 can be configured to optimize its operation. For example, a power amplifier system By configuring the system 26 in this manner, the power added efficiency (PAE) of the power amplifier 32 and It can assist in the control of linearity.

[0037] Power amplifier bias

[0038] A theoretically ideal power amplifier is linear regardless of the input or output power of the power amplifier. It has gain characteristics and phase characteristics. The gain characteristics of a power amplifier are the output amplitude change versus the input amplitude change. It can be plotted on an AM / AM graph that shows this. When used here, AM is Amplitude fluctuations can be mentioned. The theoretically ideal power amplifier, in AM / AM plots, It has a variation of 0 dB / dB. The phase characteristics of a power amplifier are the output phase change versus the input amplitude change. The AM / PM can be plotted on the AM / PM graph shown. When used here, PM is the position Phase variation can be mentioned. Similar to the ideal AM / AM characteristic, a theoretically ideal power amplifier is A The M / PM plot shows a variation of 0 dB / dB.

[0039] Real-world power amplifiers do not achieve the flat gain and phase characteristics of the theoretically ideal power amplifier. Since it is not possible to do so, one important aspect of power amplifier design is the gain characteristics of the power amplifier. And to improve the linearity of the phase characteristics. In a given implementation example, the output of the power amplifier It must not have a negative impact on power and efficiency, and the gain characteristics and phase characteristics of the power amplifier must be Achievable linearity may involve trade-offs. In a multi-stage power amplifier system, The gain characteristics and phase characteristics of each stage power amplifier in the system are as follows: The genders can be selected such that the overall gender profile is substantially linear.

[0040] Figure 4 is a schematic block diagram of another example of a power amplifier system relating to multiple aspects of this disclosure. Yes. For details, the example power amplifier system 27 includes a power amplifier bias circuit 30 and a power amplifier. Includes an amplifier stage 41, a current source 75, and a bias impedance component 80. The amplifier bias circuit 30 includes transistor 71 and two diodes 73 and 74. It may include. The components of the power amplifier bias circuit 30, together with the current source 75, power The current is arranged to generate a current mirror that mirrors the current generated by the amplifier stage 41. It can be done. The output of the power amplifier bias circuit 30 is the bias impedance capacitor. It is supplied to component 80. The bias impedance component 80 is bias It is coupled to the power amplifier stage 41 to supply the signal.

[0041] The power amplifier stage 41 receives the input RF signal RFIN and the bias impedance component It is configured to receive both the bias signal from the 80 and the power amplifier stage 41. It is configured to generate an output RF signal RFOUT based on the received signal. Power amplifier Stage 41 is a theoretically ideal power amplifier (for example, with gain characteristics and phase characteristics of 0 dB / dB (Designed to exist within a certain threshold range) It has gain and phase characteristics similar to those of a device. To generate the output RF signal RFOUT as an amplified version of the input RF signal RFIN, The power amplifier stage 41 is composed of a transistor 61, a plurality of capacitors 52, 65 and 64, and a plurality of inductors 53, 63 and 66. Capacitors 52, 65 and 6 4 and inductors 53, 63 and 66 are connected to the input RF signal RFIN and the power supply voltage Vc It is coupled to transistor 61, which receives c and generates the output RF signal RFOUT.

[0042] The base of transistor 61 is biased by the power amplifier bias circuit 30. The signal is received via the bias impedance component 80. In a given implementation example, In this context, the impedance value of the bias impedance component 80 is the transient You may choose to dominate the overall bias impedance applied to the base of the TA61. In a given implementation example, the bias impedance applied to the base of transistor 61 The output impedance and bias impedance components of transistor 71. It may be equal to the sum with the impedance value of 80. That is, the bias impedance capacitor The impedance value of component 80 is the impedance value of transistor 71 (for example, The impedance value of the IAS impedance component 80 is that of transistor 71. It is possible to select a dominant amplitude (which can be an order of magnitude larger than the pedance value). In a typical embodiment, the output impedance of transistor 71 is It is inversely proportional to the transconductance of transistor 71. As a result, for transistor 71 This results in an output impedance on the order of 10Ω.

[0043] In a predetermined embodiment, the transistor 61 is used by the power amplifier system 27i to receive and A heterojunction bipolar transistor that can be adapted to high-frequency signals designed for amplification. This may include a radiator (HBT). More specifically, HBT is used in the embodiments disclosed herein. It can have high performance and efficiency for RF power amplification. In order to appropriately generate the Miller current, the transistor 71 also, in a predetermined embodiment, It may contain HBT.

[0044] One technique for adjusting the gain and phase characteristics of a power amplifier is to adjust the base of transistor 61. By selecting a fixed bias impedance to be applied to the bias signal supplied to the system, Yes. A specific bias impedance is used for the bias impedance component 80. By selecting an impedance value, the power amplifier stage 41 is selected during its design and development. It can be implemented as follows: For example, the impedance of the bias impedance component 80 - The dance value is die variant and / or laser trimmable. It can be selected via a resistor. However, the bias impedance component The impedance value of Nent 80 is related to the gain characteristics and phase characteristics of the power amplifier system 27. To adjust and / or improve the linearity of the unit power level, modulation and frequency. It can be selected as such. That is, the power amplifier system 27 has a bias impedance Different power levels derived from the values ​​used when selecting the value of the 80 component. , when used in modulation and / or frequency, the gain characteristics and / Alternatively, the linearity of the phase characteristics may be impaired.

[0045] Therefore, certain aspects of this disclosure are applicable to applying a bias to a power amplifier. Regarding the use of variable bias impedance components. Figure 5A shows several of the present disclosure. This is a schematic block diagram of yet another example of a power amplifier system relating to the side. (Figure 5A) The components of the power amplifier system 28 are shown in Figure 4. Similar to, or substantially the same as, 27, represented by the same reference number, and its details Explanations may be omitted for the sake of clarity.

[0046] As shown in Figure 5A, the power amplifier system 28 includes a power amplifier bias circuit 30. It includes a power amplifier stage 41, a current source 75, and a bias impedance component 81. In Figure 5A, the bias impedance component is a variable bias impedance component. It can be implemented as component 85, the same as the power amplifier system 27 in Figure 4. As shown in the embodiment of Figure 5A, the output of the power amplifier bias circuit 30 is a variable bias Supplied to impedance component 85. Variable bias impedance component Nent 85 is coupled to the power amplifier stage 41 to provide a bias signal. Variable bias input The bias impedance component 85 is a variable bias impedance component 85. Configure to receive the CTRL control signal configured to adjust the impedance value. This is possible. Therefore, the impedance of the variable bias impedance component 85 The value can be adjusted based on the voltage of the control signal CTRL. In the illustrated example, The variable bias impedance component 85 is controlled by the control signal CTRL. It can be implemented using any variable impedance element (e.g., a variable resistor). .

[0047] The specified variable impedance technology is for all power amplifier systems 28, in detail. For a power amplifier that can be implemented in a mobile phone to amplify the RF signal being transmitted, It's not realistic. As mentioned above, for a given RF power amplifier application... In this configuration, it is desirable to implement the transistor 61 of the amplifier stage 41 as an HBT transistor. It seems that HBT has desirable performance characteristics and efficiency characteristics for use in RF power amplifiers. This is because it can have properties. In some semiconductor manufacturing techniques, a single semiconductor die Combining different device technologies can be difficult. For example, HBT and field effect When transistors (FETs) are combined on the same semiconductor die, the desired transistor is formed. It is not possible to obtain a device with the desired characteristics. The whole thing is incorporated here by reference. U.S. Patent No. 9,105,488(B2), granted on August 11, 2015. As explained, there have been several attempts to integrate FETs into the GaAs HBT process. Although it was attempted, only an n-type FET device was obtained. However, a US patent... Recent developments in manufacturing techniques as illustrated in Specification No. 9,105,488(B2) This enables the fabrication of HBTs and FETs on a single semiconductor die.

[0048] This technology enables the manufacture of semiconductor devices that possess both HBT and FET technologies. Figure 5B shows one embodiment of the power amplifier 28 shown in Figure 5A. This is a schematic block diagram of yet another example of a power amplifier system relating to the numerical aspect. The power amplifier 29 shown in Figure 5B includes a power amplifier bias circuit 30, a power amplifier stage 41 and This includes current sources 75, each of which is the same as or as described above in relation to Figure 5A. The same may apply. The power amplifier 29 further uses the variable bias impedance component shown in Figure 5A. Instead of component 85, use bias impedance component 81 which includes FET90. Includes. FET90 receives the control signal CTRL at its gate via an optional resistor 95. It can be configured to receive the signal. The control signal adjusts the impedance value of FET90. It is configured to be such that the impedance value of FET90 is the power of the control signal CTRL. The pressure can be adjusted by selecting it. In a typical embodiment, FET9 0 allows operation in the triode by selecting the voltage of the control signal CTRL. It is possible. As anyone skilled in the art would know, the triode region of FET90 is F The FET90 operates in a manner similar to a resistor (for example, the FET90 operates in a triode) Applicable to the gate of FET90 (which can have a substantially linear response while operating). This refers to a certain voltage range. That is, FET90 operates within the triode region. In this case, the impedance of FET90 can be controlled by the control signal CTRL. .

[0049] The value of the bias impedance supplied to the base of transistor 61 in amplifier stage 41 is This may affect the gain characteristics and phase characteristics of the power amplifier 28 or 29. In particular, Figures 6A-6 F is the effect of the change in bias impedance on the power amplifier characteristics relating to multiple aspects of this disclosure. This graph shows the results. Figures 6A to 6C show that relatively high impedance is the power amplifier's Figures 6D to 6F show the power amplifier characteristics when applied to a transistor, while Figures 6D to 6F show the relatively low This shows the power amplifier characteristics when a high impedance is applied to the transistors of a power amplifier. Figures 6A to 6F show how increasing or decreasing the bias impedance value affects the characteristics of the power amplifier. The sole purpose is to show what kind of impact it has on sexuality, so the graphs shown are not intended to be used. The specific value of the bias impedance to be applied is not limited to a given embodiment. "Low" impedance values ​​can be considered virtually zero impedance, and "high" impedance values ​​are often considered zero impedance. The impedance value can be considered as an infinite impedance value.

[0050] Figures 6A and 6D show transistors in a power amplifier (for example, the transistors in Figure 5A or 5B). The base-collector voltage (V) and base current (A) of the ZISTA 61) are set to "high" and "low" Let the input power (dBm) to the transistor under bias impedance be a function of this function. This is the graph shown. Of particular note is the input at high bias impedance in Figure 6A. As power increases, the base-collector voltage (V) decreases, while the low bias shown in Figure 6D In terms of impedance, even if the input power increases, the base-collector voltage (V) effectively remains the same. It is fixed in place.

[0051] Figures 6B and 6E show the gain (dB) and output power (dB) of a transistor in a power amplifier. Bm) is input to the transistor under "high" and "low" bias impedances. This graph shows the power as a function of the force (dBm). Here, the high bias impedance in Figure 6B - In the dance, the gain is "compressed" or "decreased" as the input power increases, while Figure 6E At low bias impedance, the gain increases with increasing input power. In other words, the bias impedance is determined by the value between the "high" and "low" values ​​shown in the diagram. By selecting this option, the gain output is flattened, and consequently, the gain linearity is improved. Therefore, the gain characteristics of the power amplifier can be improved.

[0052] Figures 6C and 6F show the output current (A) of a transistor in a power amplifier, and the "high" and The relationship between input power (dBm) to a transistor under a "low" bias impedance. This is a graph showing the values ​​numerically. Here, at the high bias impedance in Figure 6C, input With respect to power, the DC output current is practically fixed, while the low bias impedance shown in Figure 6F In dance, the DC output current increases with increasing input power.

[0053] Figure 7 shows the gain in the output stage of a power amplifier relating to multiple aspects of this disclosure, in relation to the output power. This is a graph that shows the values ​​numerically. As shown in the legend, the impedance ranges from 5Ω to 1000Ω. Various advantages at different impedance bias levels, ranging from impedance to impedance. The gain curve is shown in Figure 7. As the bias impedance increases, the output... As the power increases, the gain decreases. In the illustrated embodiment, the gain is substantially flat. To achieve this, a 50Ω impedance bias can be selected. However, other Depending on the power amplifier topology, different output stage gain plots can be obtained, so effectively The inherent impedance bias that provides a flat gain depends on the specific implementation of the power amplifier. It can exist.

[0054] Figures 8A to 8D show a certain number of power amplifier characteristics relating to multiple aspects of this disclosure. Figure 8A shows the gain of a power amplifier at a certain number of different bias impedance values. Figure 8B shows the output power as a function of (dB), and the results for different bias impedance values. Figure 8C shows the phase (deg) of a power amplifier as a function of output power, and different... The power amplifier efficiency (%) for a power amplifier at a bias impedance value is expressed as output power As shown as a function of, Figure 8D shows the power amplifier at different bias impedance values. The transistor collector current (mA) is shown as a function of output power.

[0055] As shown in Figures 8B to 8D, the bias impedance value is related to the phase and power of the power amplifier. It does not have a significant effect on the power amplifier efficiency or the transistor collector current characteristics. However, Furthermore, as shown in Figure 8A, the bias impedance value increases with increasing gate control voltage (e.g., For example, an increase in bias impedance affects the gain characteristics of the power amplifier. This results in an increase in gain as a function of output power. In other words, the bias impedance... The adjustment of the dance affects the phase of the power amplifier, the power amplifier efficiency, and the transistor collector current characteristics. It is an effective tool for adjusting the gain characteristics of a power amplifier without significantly affecting them. It is possible.

[0056] Figure 9 shows one embodiment of a multistage power amplifier system relating to multiple aspects of this disclosure. Furthermore, the power amplifier system 121 in Figure 9A has an RF input port RFIN and an RF output port The first power amplifier 120 and the second power amplifier 125 are connected in series with RFOUT. Includes. The first power amplifier 120 and the second power amplifier 125 are power amplifiers shown in Figure 5B. This may be the same as or similar to item 29. Therefore, a detailed description of each component will not be provided. This will be done. In the embodiment shown in Figure 9, the transients of each of the power amplifiers 120 and 125 The bias impedance value supplied to the base of sta 61 is the first power amplifier 120 and In each of the second power amplifiers 125, the amplifier stage 41 and the power amplifier bias circuit 30 The gate control applied to each amplifier stage 41 may be selected individually depending on the specific implementation. The bias impedance selected by the GATE CTRL voltage is determined by the power amplifier. The overall gain of stem 121 (e.g., output relative to the signal applied to input port RFIN) The gain at the port RFOUT can be selected to be sufficiently flat. Therefore, In a predetermined implementation example, the gains of the first power amplifier 120 and the second power amplifier 125 The overall gain of the power amplifier system 121 varies from an ideal fluctuation of 0 dB / dB to one As long as the fluctuations are below a certain threshold, the data will not be substantially flat.

[0057] Figure 10 is a schematic block diagram of another example of a power amplifier system relating to multiple aspects of this disclosure. The power amplifier 130 shown in Figure 10 includes a power amplifier bias circuit 30 and a power amplifier. This includes the stage 41 and the current source 75, which are described above in relation to Figures 5A and 5B. It may be the same as or similar to the one that was done. The power amplifier 130 further has a single FE in Figure 5B A bias impedance component including a pair of FETs 91 and 92 instead of T90. Includes FET 81. The control signal CTRL is sent to the corresponding gates of FET 91 and 92. It can be applied via resistors 95 and 97. Depending on the implementation, two FETs 91 and The use of FET 92 provides the impedance given by the combination of FET 91 and 92. The range of the bias value is increased while keeping FETs 91 and 92 in a triode configuration. This is possible. Although not shown in Figure 10, in order to maintain the correct current Miller ratio, The circuit structure (including two FETs and an input resistor) is included in the power amplifier bias circuit. It is possible.

[0058] Figure 11 shows schematic diagrams of further other examples of power amplifier systems relating to multiple aspects of the present disclosure. This is a lock diagram. The power amplifier 131 shown in Figure 11 is the same as the power amplifier 1 shown in Figure 10. Similar to 30, but with three or more FETs 91-92 in the bias impedance component. The difference lies in the inclusion of 81. Here, the inclusion of an additional FET is indicated by the abbreviated symbol. This is indicated. Three or more FETs 91-92 are biased into component 8 By including it in 1, it is possible to generate while maintaining FET91 and 92 in triode mode. The range of the impedance value increases. As mentioned above in relation to Figure 10, the current mirror - The same structure (same number of FETs and resistors) is included in the power amplifier bias circuit to maintain the ratio. It is possible to do so.

[0059] Musubi

[0060] Throughout this specification and the claims, unless it is evident from the context otherwise. Terms such as "include" have taken on a comprehensive meaning, the opposite of an exclusive or exhaustive meaning, i.e., "~ This should be interpreted as meaning "including but not limited to these." The word "combination" refers to either direct connection or connection via one or more intermediate elements. It refers to two or more elements that can be related. Similarly, the word "connection" is commonly used here. These can be connected directly or through one or more intermediate elements. It refers to two or more elements. In addition, it refers to the words "here," "up," "down," and similar meanings. When a word is used in this application, it refers to the entire application. This does not refer to any specific part of this application. Where the context allows, The terms used in the above detailed explanation, whether singular or plural, also include plural or singular forms. It may appear. The words "or" and "or else" which refer to a list of two or more items, are used in conjunction with the word This covers all of the following interpretations: namely, any item in the list, the list This includes all items, and any combination of items in the list.

[0061] Furthermore, especially "can," "may," "maybe," and "for example" Conditional language used here, such as "if" and "like", generally means that it is not the case that Unless otherwise stated or understood in the context of use, the given embodiments While one embodiment includes certain features, elements, and / or states, other embodiments do not include them. It is intended to convey; that is, such conditional language conveys features, elements and / or states. The state is in any state necessary for one or more embodiments, or one or more embodiments However, with or without input or prompting from the author, these characteristics, elements and / or whether the state is included in any specific embodiment or performed in such embodiment It is not generally intended to suggest that it includes the logic behind the decision.

[0062] The above detailed description of embodiments of the present invention is exclusive, i.e., the present invention is not disclosed above. It is not intended to limit the invention to a precise form. Specific embodiments of the present invention and its examples are illustrative. As stated above as the objective, as those skilled in the art will recognize, various equivalents exist within the scope of the present invention. Modification is also possible. For example, if a process or block is presented in a given order, alternative processes can be implemented. The implementation method may involve performing a routine with steps in a different order or a system with blocks. The system can be used to delete, move, add, and subdivide some processes or blocks. These processes or blocks can be combined and / or modified. It can be implemented in various different ways. Also, processes or blocks can be executed serially. Although it may appear that these processes or blocks are broken, instead, They can be done in parallel or at different times.

[0063] The teachings of the present invention given herein are not necessarily limited to the systems described above, and other It can also be applied to the system. The various embodiment elements and actions described above are further They can be combined to give an embodiment.

[0064] Although several embodiments of the present invention have been described, these embodiments are presented only as examples. This is not intended to limit the scope of this disclosure. In fact, the information described herein is These novel methods and systems can be embodied in various other forms. Furthermore, here Various omissions, substitutions, and modifications in the methods and system forms described herein are essential to this disclosure. This can be done without departing from the scope of the present disclosure. The attached claims and equivalents are within the scope of the present disclosure. It is intended to cover such forms or modifications that fit within the box and abstract.

Claims

1. A power amplifier system, A bias circuit configured to receive a bias voltage and generate a bias signal, A power amplifier configured to receive an input radio frequency signal and generate an output radio frequency signal. Steps and, A bias impedance operably coupled between the bias circuit and the power amplifier stage. lance component and Includes, The bias impedance component receives a control signal and responds to the control signal. The configuration is configured to adjust the impedance value of the bias impedance component. A power amplifier system.

2. The bias impedance component includes a transistor, The aforementioned control signal is configured to work together with the transistor in the triode. A power amplifier system according to claim 1, having pressure.

3. The aforementioned transistor includes a field-effect transistor. The power amplifier is configured to amplify the input radio frequency signal using a heterojunction bi A power amplifier system according to claim 2, comprising a polar transistor.

4. The field-effect transistor and the heterojunction bipolar transistor are single semiconductors. A power amplifier system according to claim 3, manufactured on a die.

5. The impedance value of the bias impedance component is the impedance of the power amplifier stage The electric power supply according to claim 1, selected such that the gain variation is from 0 dB / dm to less than a certain threshold. Power amplifier system.

6. An additional bias circuit configured to generate an additional bias signal upon receiving the aforementioned bias voltage. and, The output radio frequency signal is received from the power amplifier stage to generate an additional radio frequency output signal. An additional power amplifier stage configured to do so, An additional bias is operably coupled between the additional bias circuit and the additional power amplifier stage. Simpedance components and It further includes, The additional bias impedance component receives the additional control signal and the additional bias impedance In response to your signal, the impedance value of the additional bias impedance component A power amplifier system according to claim 1, configured for adjustment.

7. The impedance value of the bias impedance component and the additional bias input The impedance value of the impedance component refers to the power amplifier stage and the additional power The overall gain variation of the amplifier stage is selected to be less than a certain threshold from 0 dB / dm. The power amplifier system according to claim 6.

8. operably coupled between the bias impedance component and the power amplifier stage. Further includes an additional bias impedance component, The additional bias impedance component receives the control signal and the control signal The impedance value of the additional bias impedance component is adjusted in response to the signal. A power amplifier system according to claim 1, configured to perform the following actions.

9. A method for adjusting the gain of a power amplifier stage, In a bias circuit, receiving a bias voltage, The bias circuit generates a bias signal based on the bias voltage, In the bias impedance component, the bias voltage and control signal are received To do, In the bias impedance component, based on the received control signal Adjusting the impedance value of the bias impedance component, In the power amplifier stage, the input radio frequency signal and the bias impedance component It receives a bias voltage from the terminal, The output radio frequency signal is generated based on the input radio frequency signal and the bias voltage. thing and Methods that include...

10. The bias impedance component includes a transistor, The aforementioned control signal is configured to work together with the transistor in the triode. The method of claim 9, wherein pressure is present.

11. The aforementioned transistor includes a field-effect transistor. The power amplifier includes a heterojunction bipolar transistor. The above method further relates the input radio frequency in the heterojunction bipolar transistor. The method of claim 10, comprising amplifying a signal.

12. The field-effect transistor and the heterojunction bipolar transistor are single semiconductors. The method of claim 11, which is manufactured on a die.

13. The gain fluctuation of the power amplifier stage is set to be less than a certain threshold from 0 dB / dm. The control signal is used to obtain the impedance value of the impedance component. The method of claim 9, further comprising selecting the voltage.

14. In the additional bias impedance component, the bias impedance component Receiving the bias voltage from the power supply and the control signal, In the additional bias impedance component, based on the received control signal The impedance value of the additional bias impedance component is adjusted. and It further includes, The additional bias impedance component is the bias impedance component The method of claim 9, wherein the unit is operably coupled between the amplifier stage and the amplifier stage.

15. It is a mobile device, A power amplifier configured to amplify an input radio frequency signal and generate an output radio frequency signal. and, A modulator configured to generate a radio frequency transmission signal based on the output radio frequency signal. and Includes, The aforementioned power amplifier, A bias circuit configured to receive a bias voltage and generate a bias signal, A power supply configured to receive the input radio frequency signal and generate the output radio frequency signal. The power amplifier stage, A bias impedance operably coupled between the bias circuit and the power amplifier stage. lance component and Includes, The bias impedance component receives a control signal and responds to the control signal. The configuration is configured to adjust the impedance value of the bias impedance component. A mobile device.

16. The bias impedance component includes a transistor, The aforementioned control signal is configured to work together with the transistor in the triode. A portable device according to claim 15, having pressure.

17. The aforementioned transistor includes a field-effect transistor. The power amplifier is configured to amplify the input radio frequency signal using a heterojunction bi A portable device according to claim 16, comprising a polar transistor.

18. The field-effect transistor and the heterojunction bipolar transistor are single semiconductors. A portable device according to claim 17, manufactured on a die.

19. The impedance value of the bias impedance component is the impedance of the power amplifier stage The gain variation is selected to be less than a certain threshold from 0 dB / dm, according to claim 15. Mobile devices.

20. The power amplifier further comprises the bias impedance component and the power amplifier Includes an additional bias impedance component operably coupled between the stage, The additional bias impedance component receives the control signal and the control signal The impedance value of the additional bias impedance component is adjusted in response to the signal. A portable device according to claim 15, configured to do so.

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