Radio frequency power amplification integrated circuit and mobile terminal adopting same
Technical Field
The present invention relates to the field of radio frequency, and in particular, to a radio frequency power amplification integrated circuit having a power control function and a mobile terminal using the same.
Background
In modern wireless communication systems, a radio frequency power amplifier is a key component for realizing wireless transmission of radio frequency signals. The main function of the rf power amplifier is to amplify the modulated rf signal to a required power value, and transmit the amplified rf signal to an antenna for transmission, so as to ensure that a receiver in a certain area can receive the modulated rf signal. As a key component of the radio frequency part, the performance of the radio frequency power amplifier directly affects the communication quality, and especially in digital communication systems which are more and more widely adopted, for example, standards such as GSM (global system for mobile communications), TD-SCDMA (time division-synchronous code division multiple access), CDMA (code division multiple access), and the like.
The GSM protocol specifies that handset transmit power can be controlled by the base station. The base station sends a command to control the transmitting power level of the mobile phone through a downlink SACCH channel, the transmitting power difference between every two adjacent power levels is 2dB, the maximum transmitting power level of a GSM900 frequency band is 5 (33 dBm), the minimum transmitting power level is 19 (5 dBm), the maximum transmitting power level of a DCS1800 frequency band is 0 (30 dBm), and the minimum transmitting power level is 15 (0 dBm). For a long time, power amplifier integrated circuits designed by using gallium arsenide HBT (heterojunction bipolar transistor) technology have been the mainstream products in the mobile phone terminal market. Because the gallium arsenide HBT transistor has the characteristics of high power density and high breakdown voltage, the gallium arsenide HBT transistor is widely applied to a power amplifier of a mobile phone.
As shown in fig. 1, the GSM rf power amplifier integrated circuit mainly comprises a power controller 101 and an rf power amplifier 102, the rf power amplifier 102 is manufactured by using a gallium arsenide HBT process with high performance, and the power controller 101 is manufactured by using a Complementary Metal Oxide Semiconductor (CMOS) process with low cost.
The rf power amplifier 102 is generally formed by cascading two parts, a power driving stage 103 and a power output amplifying stage 104. The power supply for the rf power amplifier 102 is provided by the power controller 101 and the supply voltage is determined by the value of the VRAMP signal.
In order to reduce the product cost of the GSM rf power amplifier integrated circuit, the current development trend is to implement the power amplifier and the power controller by the same process, so as to reduce the manufacturing cost of the product by saving the chip area and reducing the chip package size. With the development of the integrated circuit manufacturing process level, GSM monolithically integrated power amplifier modules based on Complementary Metal Oxide Semiconductor (CMOS) process design have appeared on the market today. Since the device breakdown voltage of the CMOS process itself is generally about 6V, it is still very low compared to 15V of the gallium arsenide HBT process. Therefore, the power amplifier designed by the current Complementary Metal Oxide Semiconductor (CMOS) process adopts a Cascode structure, and the structure generally superposes two NMOS transistors, so that the breakdown voltage of the circuit can be increased to about 12V, and the power output meeting the GSM index can be realized through reasonable design. The power control method is the same as the traditional gallium arsenide power amplifier control method, namely the power supply voltage of the power amplifier is controlled to change the output power. Although the whole GSM rf power amplifier integrated circuit is implemented by fully using a Complementary Metal Oxide Semiconductor (CMOS) process, the chip area of the whole circuit is increased due to the Cascode structure, so that there is no great advantage in reducing the cost.
Specifically, as shown in fig. 1, the GSM rf power amplifier module mainly comprises a power controller 101 and an rf power amplifier 102, wherein the rf power amplifier 102 is fabricated by using a gallium arsenide (GaAs) HBT process with high performance, and the power controller 101 is fabricated by using a Complementary Metal Oxide Semiconductor (CMOS) process with low cost. The rf power amplifier 102 is generally formed by cascading two parts, a power driving stage 103 and a power output amplifying stage 104. The power supply of the rf power amplifier 102 is provided by the power controller 101. The power controller 102 is typically a low dropout regulator (LDO) with a variable output that varies its output supply voltage value by varying the value of the LDO input control voltage signal VRAMP, thereby achieving power control. Since the GSM protocol specifies that the maximum transmit power level for the GSM900 band is 5, or 33 dBm. The maximum output power is typically designed to be 35dBm, taking into account losses from the rf power amplifier to the antenna. In order to achieve a maximum output power of 35dBm for the rf power amplifier 102, the PMOS transistor 105 must be sized large enough to provide sufficient drive current.
Therefore, how to design a technology for effectively reducing the chip area of the rf power amplifying ic and the manufacturing cost of the product in the rf communication system becomes a problem to be solved.
Disclosure of Invention
The technical problem to be solved by the present invention is to provide a radio frequency power amplifying integrated circuit with a power control function and a mobile terminal using the same, so as to solve the problems that the chip area of the radio frequency power amplifying integrated circuit cannot be effectively reduced and the manufacturing cost of the product cannot be reduced at present.
In order to solve the technical problems, the invention provides a radio frequency power amplification integrated circuit with a power control function, which is formed by connecting a power controller, three power unit modules, a bias circuit and a matching circuit, and is characterized in that the three power unit modules are formed by cascading two power driving stage modules and a power output amplification stage module, and the two power driving stage modules and the power output amplification stage module are formed by overlapping BJT transistors and NMOS transistors; wherein,
the emitter of the BJT transistor is grounded, the base of the BJT transistor is a power signal input end, the collector of the BJT transistor is connected with the source of an NMOS transistor, the drain of the NMOS transistor is a power signal output end, and the grid of the NMOS transistor is controlled by a variable voltage signal generated by the power controller.
Further, the power controller is a low dropout regulator.
Further, the low dropout regulator further comprises an operational amplifier, a PMOS transistor and two resistors, wherein the drain of the PMOS transistor and the connection output end of one resistor are connected with the gates of the three NMOS transistors.
In order to solve the above technical problem, the present invention further provides a mobile terminal, wherein the mobile terminal employs any one of the rf power amplifier integrated circuits with power control function as described above, and the mobile terminal includes: the mobile terminal comprises a control chip, a radio frequency transceiver, a radio frequency power amplification integrated circuit, a low noise amplifier module, a radio frequency switch module and an antenna; wherein,
the baseband control chip is respectively connected with the radio frequency transceiver and the radio frequency power amplification integrated circuit and is used for synthesizing a baseband signal to be transmitted or decoding the received baseband signal;
the radio frequency transceiver is respectively connected with the baseband control chip, the radio frequency power amplification integrated circuit and the low noise amplifier module, and is used for processing a baseband signal transmitted from the baseband control chip to generate a radio frequency signal and sending the generated radio frequency signal to the radio frequency power amplification integrated circuit, or processing the radio frequency signal transmitted from the low noise amplifier module to generate a baseband signal and sending the generated baseband signal to the baseband control chip;
the radio frequency power amplification integrated circuit is respectively connected with the radio frequency transceiver and the radio frequency switch module and is used for carrying out power amplification processing on radio frequency signals transmitted from the radio frequency transceiver and then transmitting the radio frequency signals to the radio frequency switch module;
the low noise amplifier module is respectively connected with the radio frequency transceiver and the radio frequency switch module and is used for receiving the signal from the radio frequency switch module, processing the received signal and sending the processed signal to the radio frequency transceiver;
the radio frequency switch module is respectively connected with the radio frequency power amplification integrated circuit, the low noise amplifier module and the antenna and is used for receiving signals from the outside through the antenna and sending the signals to the low noise amplifier module or transmitting the signals transmitted from the radio frequency power amplification integrated circuit.
In order to solve the technical problem, the invention also provides a radio frequency power amplification integrated circuit with a power control function, which is formed by connecting a power controller, three power unit modules, a bias circuit and a matching circuit, and is characterized in that the three power unit modules are formed by cascading two power driving stage modules and a power output amplification stage module, wherein the power driving stage modules are respectively formed by BJT transistors, and the power output amplification stage module is formed by overlapping BJT transistors and NMOS transistors; wherein,
the emitter of the BJT transistor in the power output amplification stage module is grounded, a radio-frequency power signal enters the power output amplification stage module through the base of the BJT transistor in the power output amplification stage module, the collector of the BJT transistor in the power output amplification stage module is connected with the source of the NMOS transistor in the power output amplification stage module, the drain of the NMOS transistor in the power output amplification stage module is a radio-frequency signal output end, and the grid of the NMOS transistor in the power output amplification stage module is connected with the output contact of the power controller.
Further, the power controller is a low dropout regulator.
Further, the low dropout regulator further comprises an operational amplifier, a PMOS transistor and two resistors, wherein the drain of the PMOS transistor and the connection output end of one resistor are connected with the gate of the NMOS transistor in the power output amplifier stage module and the collectors of the two power driver stage modules.
In order to solve the above technical problem, the present invention further provides a mobile terminal, wherein the mobile terminal employs any one of the rf power amplifier integrated circuits with power control function as described above, and the mobile terminal includes: the mobile terminal comprises a control chip, a radio frequency transceiver, a radio frequency power amplification integrated circuit, a low noise amplifier module, a radio frequency switch module and an antenna; wherein,
the baseband control chip is respectively connected with the radio frequency transceiver and the radio frequency power amplification integrated circuit and is used for synthesizing a baseband signal to be transmitted or decoding the received baseband signal;
the radio frequency transceiver is respectively connected with the baseband control chip, the radio frequency power amplification integrated circuit and the low noise amplifier module, and is used for processing a baseband signal transmitted from the baseband control chip to generate a radio frequency signal and sending the generated radio frequency signal to the radio frequency power amplification integrated circuit, or processing the radio frequency signal transmitted from the low noise amplifier module to generate a baseband signal and sending the generated baseband signal to the baseband control chip;
the radio frequency power amplification integrated circuit is respectively connected with the radio frequency transceiver and the radio frequency switch module and is used for carrying out power amplification processing on radio frequency signals transmitted from the radio frequency transceiver and then transmitting the radio frequency signals to the radio frequency switch module;
the low noise amplifier module is respectively connected with the radio frequency transceiver and the radio frequency switch module and is used for receiving the signal from the radio frequency switch module, processing the received signal and sending the processed signal to the radio frequency transceiver;
the radio frequency switch module is respectively connected with the radio frequency power amplification integrated circuit, the low noise amplifier module and the antenna and is used for receiving signals from the outside through the antenna and sending the signals to the low noise amplifier module or transmitting the signals transmitted from the radio frequency power amplification integrated circuit.
Compared with the prior art, the radio frequency power amplification integrated circuit with the power control function and the mobile terminal adopting the same achieve the following effects:
1) the invention relates to a radio frequency power amplification integrated circuit with a power control function and a mobile terminal adopting the same. The output power of the amplifier is controlled by controlling the gate voltage of the NMOS transistor.
2) In the radio frequency power amplification integrated circuit with the power control function and the mobile terminal adopting the same, in the circuit structure, the NMOS transistor is superposed on the BJT transistor, so that the pressure of the breakdown voltage of the BJT transistor is reduced, the swing of the output voltage of the power amplifier is improved, the requirement on the maximum current capacity of the BJT transistor is reduced, the size of the output transistor is reduced, the chip area is further reduced, and the manufacturing cost is also reduced.
Drawings
Fig. 1 is a schematic diagram of a GSM radio frequency power amplifier in the prior art.
Fig. 2 is a block diagram of an rf power amplifier integrated circuit with power control function according to a first embodiment of the present invention.
Fig. 3 is a specific circuit diagram of an rf power amplifier integrated circuit with power control function according to a first embodiment of the present invention.
Fig. 4 is a schematic circuit diagram of a power output amplifier stage module in a radio frequency power amplifier integrated circuit with a power control function according to a first embodiment of the present invention.
Fig. 5 is a specific circuit diagram of a radio frequency power amplifier integrated circuit with power control function according to the second embodiment of the present invention.
Fig. 6 is a block diagram of a connection structure of a mobile terminal using a radio frequency power amplifier integrated circuit with a power control function according to one or two embodiments of the present invention.
Detailed Description
As used in the specification and in the claims, certain terms are used to refer to particular components. As one skilled in the art will appreciate, manufacturers may refer to a component by different names. This specification and claims do not intend to distinguish between components that differ in name but not function. In the following description and in the claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to. "substantially" means within an acceptable error range, within which a person skilled in the art can solve the technical problem to substantially achieve the technical result. Furthermore, the term "coupled" is intended to encompass any direct or indirect electrical coupling. Thus, if a first device couples to a second device, that connection may be through a direct electrical coupling or through an indirect electrical coupling via other devices and couplings. The following description is of the preferred embodiment for carrying out the invention, and is made for the purpose of illustrating the general principles of the invention and not for the purpose of limiting the scope of the invention. The scope of the present invention is defined by the appended claims.
The present invention will be described in further detail below with reference to the accompanying drawings, but the present invention is not limited thereto.
As shown in fig. 2 and 3, a rf power amplifier integrated circuit 2 with power control function according to a first embodiment of the present invention is formed by connecting a power controller 21, three power cell modules (powercells) 204, 205, 206, a bias circuit 207 and a matching circuit 208, and is characterized in that the three power cell modules 204, 205, 206 are formed by cascading two power driver stage modules 204, 205 and a power output amplifier stage module 206, and the two power driver stage modules 204, 205 and the power output amplifier stage module 206 are formed by stacking bjt (bipolar junction transistor) transistors Q1, Q2, Q3 and NMOS (N-Metal-Oxide-Semiconductor) transistors M1, M2, and M3; wherein,
the emitter electrodes of the BJT transistors Q1, Q2 and Q3 are grounded, the base electrodes of the BJT transistors Q1, Q2 and Q3 are power signal input ends, the collector electrodes of the BJT transistors Q1, Q2 and Q3 are connected with the source electrodes of NMOS transistors M1, M2 and M3, the drain electrodes of the NMOS transistors M1, M2 and M3 are power signal output ends, and the grid electrodes of the NMOS transistors M1, M2 and M3 are controlled by a variable voltage signal generated by the power controller 21.
As shown in fig. 3, the power controller 21 is an LDO (low dropout regulator), and is composed of an operational amplifier 202, a PMOS (P-Metal-Oxide-Semiconductor) transistor 203, and resistors R1 and R2. The value of the output voltage of the LDO at node 209 is changed by changing the value of the input control voltage signal VRAMP. Since the power controller 21 is a prior art, it connects the drains of the PMOS transistors 203 and the connection output terminal 209 of the resistor R1 to the gates of the NMOS transistors M1, M2, M3. The power controller 21 is designed so that it does not need to have a large drive current capability, and therefore the size of the PMOS transistor 203 can be made very small.
As shown in fig. 3, the power driving stage module 204 is formed by overlapping a BJT transistor Q1 and an NMOS transistor M1. Wherein the emitter of the BJT transistor Q1 is grounded, the rf power signal enters the power driving stage module 204 through the base of the BJT transistor Q1, the collector of the BJT transistor Q1 is connected to the source of the NMOS transistor M1, the drain of the NMOS transistor M1 is the rf signal output terminal, and the gate of the NMOS transistor M1 is connected to the output terminal 209 of the power controller 21. The purpose is to control the gate voltage of the NMOS transistor M1 by changing the output voltage of the node 209, and thus control the output power of the power driver stage module 204.
As shown in fig. 3, the power driving stage module 205 is formed by overlapping a BJT transistor Q2 and an NMOS transistor M2. Wherein the emitter of the BJT transistor Q2 is grounded, the rf power signal enters the power driving stage module 205 through the base of the BJT transistor Q2, the collector of the BJT transistor Q2 is connected to the source of the NMOS transistor M2, the drain of the NMOS transistor M2 is the rf signal output terminal, and the gate of the NMOS transistor M2 is connected to the output terminal 209 of the power controller 21. The purpose is to control the gate voltage of the NMOS transistor M2 by changing the output voltage of the node 209, and thus control the output power of the power driver stage module 205.
As shown in fig. 3, the power output amplifier stage module 206 is formed by stacking a BJT transistor Q3 and an NMOS transistor M3. Wherein the emitter of the BJT transistor Q3 is grounded, the rf power signal enters the power output amplifier stage module 206 through the base of the BJT transistor Q3, the collector of the BJT transistor Q3 is connected to the source of the NMOS transistor M3, the drain of the NMOS transistor M3 is the rf signal output terminal, and the gate of the NMOS transistor M3 is connected to the output terminal 209 of the power controller 21. The purpose is to control the gate voltage of the NMOS transistor M3 by changing the output voltage of the node 209, and thus control the output power of the power output amplifier stage module 206.
In addition, as shown in fig. 4, the power output amplifier stage module is shown, wherein the highest voltage borne between the gate and the drain of the NMOS transistor M3 is
VDG_max=Vout_max-VCT
Wherein, Vout_maxIs the maximum value of the output voltage of the rf power amplifier, and VCT is the control voltage applied to the gate of the NMOS transistor M3. While the voltage experienced between the base and collector of the lower BJT transistor Q3 is
VBC=VCAS-VIN
Wherein, VCASIs the source voltage, V, of the NMOS transistor M3INIs the input voltage. When V isINWhen decreasing, VCASIncrease when VCASIncrease to VCT-Vth(threshold voltage), the NMOS transistor M3 is turned off, so the highest voltage between the base and collector of the transistor Q3 is
VBC(MAX)=VCT-Vth-VIN(MIN)
Under normal conditions, VBC(MAX)Less than the breakdown voltage of the gate oxide of the transistor (>2 VDD) the breakdown voltage of the NMOS transistor M3 is the primary factor limiting the output voltage swing. In order that the NMOS transistor M3 does not break down, it is necessary to satisfy:
Vout_max=VCT+VOX_max
wherein, VOX_maxIt is the highest voltage that the gate oxide layer can withstand without breakdown. Increasing the gate voltage of the NMOS transistor M3 can increase the output voltage swing, typically VCT = VDD, assuming VOX_max=2VDD, the maximum output voltage of the rf power amplifier is 3VDD after the technology of stacking the BJT transistor and the NMOS transistor is adopted, and when the technology is not adopted, the maximum output voltage is only 2VDD + VIN(MIN),VIN(MIN)Usually 0 or even negative, so the peak value of the output voltage can be improved by about 1.5 times at least by adopting the technology, and the requirement on the maximum current capability of the transistor is effectively reduced.
Fig. 5 is a schematic diagram of an rf power amplifier integrated circuit with power control function according to a second embodiment of the present invention. Since the GSM protocol specifies that the maximum transmit power level for the GSM900 band is 5, or 33 dBm. The maximum output power is typically designed to be 35dBm, taking into account losses from the rf power amplifier to the antenna. In general, the power driving stage module of the rf power amplifier is smaller than the output power of the power output amplifier by about 10dB, so that the maximum output power of the power driving stage module is designed to be 25dBm, which can meet the system emission index. Through reasonable impedance matching design, the voltage swing of the output end of the power driving level module can be enabled not to exceed the breakdown voltage of the double-click transistor completely, and for a BiCMOS (bipolar complementary metal oxide semiconductor) process, the breakdown voltage of the NPN (negative-positive-negative) transistor is about 8V.
The rf power amplifier integrated circuit with power control function according to the second embodiment is formed by connecting a power controller 41, three power cell modules (PowerCell) 404, 405, 406, a bias circuit 407 and a matching circuit 408, wherein the three power cell modules 404, 405, 406 are formed by cascading two power driver stage modules 404, 405 and a power output amplifier stage module 406, wherein,
the power driving stage modules 404 and 405 are both composed of BJT transistors Q1 and Q2, and the power output amplification stage module 406 is formed by overlapping a BJT transistor Q3 and an NMOS transistor M3; wherein, the emitter of the BJT transistor Q3 is grounded, the rf power signal enters the power output amplifier stage module 406 through the base of the BJT transistor Q3, the collector of the BJT transistor Q3 is connected to the source of the NMOS transistor M3, the drain of the NMOS transistor M3 is the rf signal output terminal, and the gate of the NMOS transistor M3 is connected to the output contact 409 of the power controller 41.
The second embodiment of the invention has the following functions: the output power of the power output amplifier stage module 406 can be controlled by controlling the voltage of the collector of the Q1, controlling the output power of the Q2, and changing the output voltage of the junction 409, so that the gate voltage of the M3 can be controlled. The power controller 41 is an LDO, and is composed of an operational amplifier 402, a PMOS transistor 403, and resistors R1 and R2. The value of the output voltage of the LDO at node 409 is changed by changing the value of the input control voltage signal VRAMP. The output of the LDO is connected with the grid of M3, the collector of Q1 and the collector of Q2. Since the maximum output power of the power driver stage modules 404 and 405 is only 25dBm, the required driving current is about 400mA, and the maximum output power of the power output amplifier stage module 406 is about 35dBm, which is about 1.5A. Therefore, compared to the conventional power control scheme in fig. 1, this control scheme does not require the LDO to have a large drive current capability, and thus the PMOS transistor 403 can be made very small in size.
Fig. 5 is a schematic structural diagram of a mobile terminal manufactured by using the first or second embodiment of the present invention. The mobile terminal includes: a baseband control chip 111, a radio frequency transceiver 112, a radio frequency power amplification integrated circuit 113, a low noise amplifier module 115, a radio frequency switch module 116, and an antenna 114. Wherein,
the baseband control chip 111 is respectively connected to the rf transceiver 112 and the rf power amplifier ic 113, and is configured to synthesize a baseband signal to be transmitted or decode a received baseband signal;
the radio frequency transceiver 112 is respectively connected to the baseband control chip 111, the radio frequency power amplification integrated circuit 113, and the low noise amplifier module 115, and is configured to process a baseband signal transmitted from the baseband control chip 111 to generate a radio frequency signal and send the generated radio frequency signal to the radio frequency power amplification integrated circuit 113, or process a radio frequency signal transmitted from the low noise amplifier module 115 to generate a baseband signal and send the generated baseband signal to the baseband control chip 111;
the rf power amplifying ic 113 is respectively connected to the rf transceiver 112 and the rf switch module 116, and configured to perform processing, such as power amplification, on the rf signal transmitted from the rf transceiver 112 and then send the rf signal to the rf switch module 116;
the low noise amplifier module 115 is connected to the rf transceiver 112 and the rf switch module 116, respectively, and configured to receive a signal from the rf switch module 116, process the received signal, and send the processed signal to the rf transceiver 112;
the rf switch module 116 is respectively connected to the rf power amplifier ic 113, the low noise amplifier module 115 and the antenna 114, and is configured to receive a signal from the outside and send the signal to the low noise amplifier module 115 through the antenna 114 or transmit a signal transmitted from the rf power amplifier ic 113.
Specifically, when transmitting signals, the baseband control chip 111 compiles information to be transmitted into baseband codes (baseband signals) and transmits the baseband codes to the rf transceiver 112, the rf transceiver 112 processes the baseband signals to generate rf signals and transmits the rf signals to the rf power amplifier ic 113, and the rf power amplifier ic 113 power-amplifies the rf signals transmitted from the rf transceiver 112 and transmits the rf signals to the outside through the rf switch module 116 and the antenna 114; when receiving signals, the low noise amplifier module 115 transmits the received radio frequency signals to the radio frequency signal transceiver 112 through the radio frequency switch module 116 and the antenna 114, the radio frequency signal transceiver 112 converts the radio frequency signals received from the low noise amplifier module 115 into baseband signals, and transmits the baseband signals to the baseband control chip 111, and finally the baseband control chip 111 interprets the baseband signals transmitted from the radio frequency transceiver 112 into received information.
Optionally, the information to be transmitted or the received information may include audio information, address information (e.g., a mobile phone number or a website address), text information (e.g., short message text or website text), picture information, and the like. The main components of the baseband control chip 111 are a processor (such as DSP, ARM, etc.) and a memory (such as SRAM, Flash, etc.). Alternatively, the baseband control chip 111 is implemented by a single chip.
Both the first and second embodiments are fabricated by using a BiCMOS process, and it should be noted that BiCMOS (bipolarcmos) is a new generation of high performance VLSI process following CMOS. CMOS has become the mainstream technology of 80 years VLSI with low power consumption and high density. Circuit performance continues to improve with the scaling down of the dimensions, but its potential is greatly limited when the dimensions are reduced below 1um due to carrier velocity saturation, etc. The CMOS and the Bipolar are integrated on the same chip, the advantages of the CMOS and the Bipolar are exerted, the defects are overcome, and the circuit can achieve high speed and low power consumption. The BiCMOS process is generally based on a CMOS process, and a small number of process steps are added. Bicmos (bipolar CMOS) is a technology in which CMOS and bipolar devices are simultaneously integrated on the same chip, and the basic idea is to use CMOS devices as main unit circuits and add bipolar devices or circuits where driving of large capacitive loads is required. Therefore, the BiCMOS circuit has the advantages of high integration level and low power consumption of the CMOS circuit, and also has the advantages of high speed and strong current driving capability of the bipolar circuit.
The invention uses BiCMOS technology to integrate the power controller and the radio frequency power amplifier (namely three power unit modules) on one chip, changes the traditional power control and controls the output power of the amplifier by controlling the grid voltage of the NMOS transistor. In the circuit structure, the NMOS transistor is superposed on the BJT transistor, so that the pressure of the breakdown voltage of the BJT transistor is reduced, the swing of the output voltage of the power amplifier is improved, the requirement on the maximum current capacity of the BJT transistor is reduced, the size of the output transistor is reduced, the chip area is reduced, and the manufacturing cost is reduced.
Compared with the prior art, the radio frequency power amplification integrated circuit with the power control function and the mobile terminal adopting the same achieve the following effects:
1) the invention relates to a radio frequency power amplification integrated circuit with a power control function and a mobile terminal adopting the same. The output power of the amplifier is controlled by controlling the gate voltage of the NMOS transistor.
2) In the radio frequency power amplification integrated circuit with the power control function and the mobile terminal adopting the same, in the circuit structure, the NMOS transistor is superposed on the BJT transistor, so that the pressure of the breakdown voltage of the BJT transistor is reduced, the swing of the output voltage of the power amplifier is improved, the requirement on the maximum current capacity of the BJT transistor is reduced, the size of the output transistor is reduced, the chip area is further reduced, and the manufacturing cost is also reduced.
The foregoing description shows and describes several preferred embodiments of the invention, but as aforementioned, it is to be understood that the invention is not limited to the forms disclosed herein, but is not to be construed as excluding other embodiments and is capable of use in various other combinations, modifications, and environments and is capable of changes within the scope of the inventive concept as expressed herein, commensurate with the above teachings, or the skill or knowledge of the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.