Amplifiers and RF ICs

Abstract

The present invention is applicable to the field of electronic circuit technology, and provides an amplifier and a radio frequency integrated circuit, wherein the amplifier comprises: an amplifying unit, a first biasing unit, a second biasing unit and a first feedback unit; wherein the amplifying unit comprises a first field effect transistor and a second field effect transistor; the first field effect transistor and the second field effect transistor are connected in series; the first biasing unit provides a bias voltage for the first field effect transistor, and the second biasing unit provides a bias voltage for the second field effect transistor; the first feedback unit provides a feedback voltage signal for the first field effect transistor; the amplifying unit of the present invention adopts a common source and common gate structure, and at the same time introduces a feedback signal through the first feedback unit, so that the amplifier has low noise and has good gain flatness in a wider frequency band, and at the same time meets the requirements of low noise, wide frequency band and high gain.

Description

Technical Field

[0001] The present invention belongs to the technical field of electronic circuits, and in particular relates to an amplifier and a radio frequency integrated circuit. Background Art

[0002] With the development of the fifth generation of mobile communication technology, the communication system's requirements for RF front-end chips are becoming more and more complex, and the frequency band requirements are becoming wider and wider. As a common component in RF front-end chips, amplifiers also have higher requirements.

[0003] The existing common-source low noise amplifier has a good noise figure, but has deficiencies in bandwidth and signal gain, and cannot simultaneously meet the communication system's requirements for low noise, wide bandwidth and high gain of the RF front-end amplifier. Summary of the invention

[0004] In view of this, an embodiment of the present invention provides an amplifier and a radio frequency integrated circuit to solve the problem in the prior art that the amplifier cannot simultaneously meet the requirements of low noise, wide bandwidth and high gain.

[0005] A first aspect of an embodiment of the present invention provides an amplifier, comprising: an amplification unit, a first bias unit, a second bias unit and a first feedback unit;

[0006] Wherein, the amplification unit includes a first field effect transistor and a second field effect transistor; the first field effect transistor and the second field effect transistor are connected in series;

[0007] The first bias unit is connected to the first end of the amplifying unit and is used to provide a bias voltage for the first field effect transistor;

[0008] The second bias unit is connected to the second end of the amplifying unit and is used to provide a bias voltage for the second field effect transistor;

[0009] The first end of the first feedback unit is connected to the fourth end of the amplifying unit; the second end of the first feedback unit is connected to the first end of the amplifying unit, and is used to provide a feedback voltage signal for the first field effect transistor;

[0010] The third terminal of the amplifying unit inputs the radio frequency signal, and the fourth terminal of the amplifying unit outputs the amplified radio frequency signal.

[0011] Optionally, the second bias unit includes: a third field effect transistor, a sixth resistor, a seventh resistor, an eighth resistor and a seventh capacitor;

[0012] a third field effect transistor, having a gate connected to the first end of the seventh resistor, the first end of the seventh capacitor and the first end of the eighth resistor, a drain connected to the second end of the seventh resistor and the first end of the sixth resistor, and a source grounded;

[0013] The second end of the seventh capacitor is grounded; the second end of the eighth resistor is connected to the second end of the amplification unit; and the second end of the sixth resistor is connected to the second power supply end.

[0014] Optionally, the third field effect transistor is a gallium arsenide-based enhancement mode pseudo-matched high electron mobility transistor.

[0015] Optionally, the second bias unit includes: a fourth field effect transistor, a fifth field effect transistor, a ninth resistor, a tenth resistor, an eighth capacitor and a ninth capacitor;

[0016] a fourth field effect transistor, the gate of which is respectively connected to the first end of the ninth resistor, the first end of the eighth capacitor and the drain of the fifth field effect transistor, the drain of which is respectively connected to the second power supply terminal and the second end of the ninth resistor, and the source of which is respectively connected to the gate of the fifth field effect transistor, the first end of the ninth capacitor and the first end of the tenth resistor;

[0017] The source of the fifth field effect transistor is grounded; the second end of the tenth resistor is connected to the second end of the amplifying unit; the second end of the eighth capacitor and the second end of the ninth capacitor are both grounded.

[0018] Optionally, the fourth field effect transistor and the fifth field effect transistor are both gallium arsenide-based enhancement-mode pseudo-matched high electron mobility transistors.

[0019] Optionally, the first bias unit includes: a fourth resistor and a fifth resistor;

[0020] a fourth resistor, a first end of which is connected to the first power supply terminal VCC, and a second end of which is respectively connected to the first end of the fifth resistor and the first end of the amplifying unit;

[0021] A second terminal of the fifth resistor is grounded.

[0022] Optionally, the first feedback unit includes: a second resistor, a third resistor, a fifth capacitor and a sixth capacitor;

[0023] a fifth capacitor, a first end of which is connected to the first end of the second resistor, and a second end of which is respectively connected to the first end of the third resistor and the second end of the first feedback unit;

[0024] a sixth capacitor, a first end of which is connected to the second end of the third resistor, and a second end of which is grounded;

[0025] The second end of the second resistor is connected to the first end of the first feedback unit.

[0026] Optionally, the amplifying unit further includes: a first inductor, a second inductor, a third inductor, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor and a first resistor;

[0027] a first field effect transistor, a gate connected to the first end of the amplifying unit and the first end of the second capacitor respectively, a drain connected to the first end of the third inductor respectively, and a source connected to the first end of the first capacitor, the first end of the second inductor and the first end of the third capacitor respectively;

[0028] a second field effect transistor, wherein the gate is respectively connected to the third end of the amplifying unit and the first end of the first resistor, the drain is respectively connected to the second end of the second inductor, the second end of the second capacitor and the first end of the fourth capacitor, and the source is grounded through the first inductor;

[0029] The second end of the third inductor is connected to the second power supply end and the fourth end of the amplifying unit respectively; the second end of the third capacitor and the second end of the fourth capacitor are both grounded; the second end of the first capacitor is connected to the second end of the first resistor and the second end of the amplifying unit respectively.

[0030] Optionally, the first field effect transistor and the second field effect transistor are both gallium arsenide-based enhancement-mode pseudo-matched high electron mobility transistors.

[0031] A second aspect of the embodiments of the present invention provides a radio frequency integrated circuit, comprising the amplifier provided by the first aspect of the embodiments of the present invention.

[0032] An embodiment of the present invention provides an amplifier and a radio frequency integrated circuit, wherein the amplifier comprises: an amplifying unit, a first biasing unit, a second biasing unit and a first feedback unit; wherein the amplifying unit comprises a first field effect transistor and a second field effect transistor; the first field effect transistor and the second field effect transistor are connected in series; the first biasing unit provides a bias voltage for the first field effect transistor, and the second biasing unit provides a bias voltage for the second field effect transistor; the first feedback unit provides a feedback voltage signal for the first field effect transistor; the amplifying unit of the present invention adopts a common source and common gate structure, with high gain and low noise, and the first feedback unit introduces feedback, thereby improving the linearity and stability of the circuit, so that the amplifier has low noise and good gain flatness in a wider frequency band, while meeting the requirements of low noise, wide frequency band and high gain. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0034] Figure 1 is a schematic diagram of a circuit structure of an amplifier provided by an embodiment of the present invention;

[0035] Figure 2is a circuit schematic diagram of an amplifier provided by an embodiment of the present invention;

[0036] Figure 3 This is a circuit schematic diagram of another amplifier provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0037] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present invention.

[0038] In order to illustrate the technical solution of the present invention, a specific embodiment is provided below for illustration.

[0039] refer to Figure 1 , an embodiment of the present invention provides an amplifier, comprising: an amplifying unit 11, a first biasing unit 12, a second biasing unit 13 and a first feedback unit 14;

[0040] The amplifying unit 11 includes a first field effect transistor E1 and a second field effect transistor E2; the first field effect transistor E1 and the second field effect transistor E2 are connected in series;

[0041] The first bias unit 12 is connected to the first end of the amplifying unit 11 and is used to provide a bias voltage for the first field effect transistor E1;

[0042] The second bias unit 13 is connected to the second end of the amplifying unit 11 and is used to provide a bias voltage for the second field effect transistor E2;

[0043] A first end of the first feedback unit 14 is connected to a fourth end of the amplifying unit 11; a second end of the first feedback unit 14 is connected to a first end of the amplifying unit 11, and is used to provide a feedback voltage signal for the first field effect transistor E1;

[0044] The third terminal of the amplifying unit 11 inputs the radio frequency signal, and the fourth terminal of the amplifying unit 11 outputs the amplified radio frequency signal.

[0045] The amplifying unit of the embodiment of the present invention adopts a common source and common gate structure with high gain and low noise. At the same time, the first feedback unit introduces a feedback mechanism to improve the linearity and stability of the circuit, so that the amplifier has low noise and good gain flatness within a wider frequency band, which can simultaneously meet the requirements of low noise, wide bandwidth and high gain.

[0046] In some embodiments, reference Figure 2The second bias unit 13 may include: a third field effect transistor E3, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8 and a seventh capacitor C7.

[0047] The third field effect transistor E3 has a gate connected to the first end of the seventh resistor R7, the first end of the seventh capacitor C7 and the first end of the eighth resistor R8, a drain connected to the second end of the seventh resistor R7 and the first end of the sixth resistor R6, and a source connected to ground; the second end of the seventh capacitor C7 is grounded; the second end of the eighth resistor R8 is connected to the second end of the amplification unit 11; and the second end of the sixth resistor R6 is connected to the second power supply terminal Vbias.

[0048] The eighth resistor R8 is a gate feeding resistor, and the seventh capacitor C7 is a decoupling capacitor. The current flowing through the sixth resistor R6 is approximately equal to the drain current of the third field effect transistor E3. The current I flowing through the sixth resistor R6 is ref =(Vbias-Vgs) / R6, where Vbias is the voltage of the second power supply terminal Vbias, and Vgs is the gate-source bias voltage of the third field effect transistor E3. The third field effect transistor E3 provides a gate voltage for the second field effect transistor E2 of the amplification unit 11 through the eighth resistor R8. The gate voltage of the third field effect transistor E3 is consistent with that of the second field effect transistor E2. The drain current I of the second field effect transistor E2 is mirrored. d The drain current I ref Mirror image, I d =I ref =(Vbias-Vgs) / R6. It can be seen that the drain current of the second field effect transistor E2 is only related to the sixth resistor R6, which improves the temperature consistency and process consistency of the amplifier. The static operating point of the second field effect transistor E2 can be adjusted by the sixth resistor R6.

[0049] In some embodiments, the third field effect transistor E3 may be a GaAs-based enhanced pseudo-matched high electron mobility transistor (GaAs-enhanced PHEMT transistor). GaAs-based enhanced pseudo-matched high electron mobility transistor has the characteristics of low noise, high gain, good linearity, etc., which can effectively reduce the noise of the amplifier and improve the gain and linearity of the amplifier.

[0050] In some embodiments, reference Figure 3 , the second bias unit 13 may include: a fourth field effect transistor E4, a fifth field effect transistor E5, a ninth resistor R9, a tenth resistor R10, an eighth capacitor C8 and a ninth capacitor C9;

[0051] The fourth field effect transistor E4 has a gate connected to the first end of the ninth resistor R9, the first end of the eighth capacitor C8 and the drain of the fifth field effect transistor E5, a drain connected to the second power supply terminal Vbias and the second end of the ninth resistor R9, and a source connected to the gate of the fifth field effect transistor E5, the first end of the ninth capacitor C9 and the first end of the tenth resistor R10; the source of the fifth field effect transistor E5 is grounded; the second end of the tenth resistor R10 is connected to the second end of the amplification unit 11; the second end of the eighth capacitor C8 and the second end of the ninth capacitor C9 are both grounded.

[0052] The fourth field effect transistor E4 drives the gate of the fifth field effect transistor E5, and the eighth capacitor C8 and the ninth capacitor C9 are both decoupling capacitors. The fifth field effect transistor E5 and the second field effect transistor E2 form a mirror image. As above, the drain current of the second field effect transistor E2 is only related to the ninth resistor R9, which improves the temperature consistency and process consistency of the amplifier. The static operating point of the second field effect transistor E2 can be adjusted by the ninth resistor R9. A part of the RF signal coupled to the source of the fourth field effect transistor E4 is coupled to the ground through the gate Schottky diode of the fourth field effect transistor E4 and the eighth capacitor C8, and a part is coupled to the ground through the ninth capacitor C9, so that the overall bias circuit has a dynamic compensation characteristic, which improves the RF performance of the circuit.

[0053] In some embodiments, the fourth field effect transistor E4 and the fifth field effect transistor E5 can be GaAs-based enhancement-mode pseudo-matched high electron mobility transistors. GaAs-based enhancement-mode pseudo-matched high electron mobility transistors have the characteristics of low noise, high gain and good linearity, which can effectively reduce the noise of the amplifier and improve the gain and linearity of the amplifier.

[0054] refer to Figure 2 and Figure 3 In some embodiments, the first bias unit 12 may include: a fourth resistor R4 and a fifth resistor R5.

[0055] The fourth resistor R4 has a first end connected to the first power supply end VCC, and a second end connected to the first end of the fifth resistor R5 and the first end of the amplifying unit 11 respectively; the second end of the fifth resistor R5 is grounded.

[0056] In some embodiments, the first feedback unit 14 may include: a second resistor R2 , a third resistor R3 , a fifth capacitor C5 , and a sixth capacitor C6 .

[0057] The fifth capacitor C5 has a first end connected to the first end of the second resistor R2, and a second end connected to the first end of the third resistor R3 and the second end of the first feedback unit 14 respectively; the sixth capacitor C6 has a first end connected to the second end of the third resistor R3, and a second end grounded; the second end of the second resistor R2 is connected to the first end of the first feedback unit 14.

[0058] The second resistor R2 and the fifth capacitor C5 can feed back the amplified RF signal to the gate of the first field effect transistor E1, adjust the phase of the gate voltage of the first field effect transistor E1, and improve the linearity of the amplifier. The third resistor R3 and the fifth capacitor C5 can increase the ground impedance of the gate of the first field effect transistor E1, and increase the frequency range of the amplifier. By adding the first feedback unit 14, the high-frequency stability of the circuit is improved, the noise coefficient is reduced, the nonlinear distortion is reduced, and the stability of the circuit is improved.

[0059] In some embodiments, the amplifying unit 11 may further include: a first inductor L1, a second inductor L2, a third inductor L3, a first capacitor C1, a second capacitor C2, a third capacitor C3, a fourth capacitor C4 and a first resistor R1.

[0060] The first field effect transistor E1 has a gate connected to the first end of the amplifying unit 11 and the first end of the second capacitor C2, a drain connected to the first end of the third inductor L3, and a source connected to the first end of the first capacitor C1, the first end of the second inductor L2, and the first end of the third capacitor C3.

[0061] The second field effect transistor E2 has a gate connected to the third end of the amplifying unit 11 and the first end of the first resistor R1, a drain connected to the second end of the second inductor L2, the second end of the second capacitor C2 and the first end of the fourth capacitor C4, and a source grounded through the first inductor L1.

[0062] The second end of the third inductor L3 is connected to the second power supply terminal Vbias and the fourth end of the amplifier unit 11 respectively; the second end of the third capacitor C3 and the second end of the fourth capacitor C4 are both grounded; the second end of the first capacitor C1 is connected to the second end of the first resistor R1 and the second end of the amplifier unit 11 respectively.

[0063] The second power supply terminal Vbias is connected to the fourth terminal (outputting the amplified RF signal) of the amplifier unit 11, and the second power supply terminal is multiplexed with the RF signal output, thereby simplifying the device structure.

[0064] The second field effect transistor E2 is a first-stage common source amplifier stage, the first field effect transistor E1 is a second-stage common gate amplifier stage, and the current flowing through the first field effect transistor E1 and the second field effect transistor E2 is the same. The second capacitor C2 is a radio frequency coupling capacitor between the two stages, the third capacitor C3 is a source bypass capacitor of the first field effect transistor E1, and the fourth capacitor C4 is a drain matching capacitor of the second field effect transistor E2. The second inductor L2 is a matching inductor between the two stages. The first resistor R1 and the first capacitor C1 form a second feedback unit, which is used to provide feedback for the second field effect transistor E2, thereby improving the stability and bandwidth of the circuit.

[0065] The device values ​​of each component are reasonably set. When the operating frequency is low, the impedance of the second inductor L2 is smaller than that of the second capacitor C2, and the RF impedance of the third capacitor C3 is higher. At this time, the signal is coupled to the source of the first field effect transistor E1 through the second inductor L2, and the first field effect transistor E1 works in the common gate amplification state; when the operating frequency is high, the impedance of the second inductor L2 is larger than that of the second capacitor C2, and the RF impedance of the third capacitor C3 is reduced. The source of the first field effect transistor E1 is bypassed to the ground through C3, and the signal is coupled to the gate of the first field effect transistor E1 through the second capacitor C2. At this time, the first field effect transistor E1 works in the common source amplification state. Since the common source stage circuit has a higher voltage gain than the common gate stage circuit, the amplifier unit provided in the embodiment of the present invention has a larger output gain when the operating frequency is high, that is, the gain characteristics of the high frequency band are improved, thereby improving the gain flatness of the circuit in the full frequency band.

[0066] In some embodiments, the first field effect transistor E1 and the second field effect transistor E2 may be GaAs-based enhancement mode pseudo-high electron mobility transistors.

[0067] GaAs-based enhancement-mode pseudo-matched high electron mobility transistor has low noise and high linearity, which can effectively reduce the noise of the amplifier and improve the linearity of the amplifier.

[0068] In some embodiments, the voltage of the first power terminal VCC may be +5V, and the voltage of the second power terminal Vbias may be obtained by dividing the voltage of the first power terminal VCC.

[0069] An embodiment of the present invention further provides a radio frequency integrated circuit, comprising the amplifier in the above embodiment.

[0070] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. An amplifier, characterized in that: include: an amplifying unit, a first biasing unit, a second biasing unit and a first feedback unit; Wherein, the amplification unit includes a first field effect transistor and a second field effect transistor; the first field effect transistor and the second field effect transistor are connected in series; The first bias unit is connected to the first end of the amplifying unit and is used to provide a bias voltage for the first field effect transistor; The second bias unit is connected to the second end of the amplifying unit and is used to provide a bias voltage for the second field effect transistor; The first end of the first feedback unit is connected to the fourth end of the amplifying unit; the second end of the first feedback unit is connected to the first end of the amplifying unit, and is used to provide a feedback voltage signal for the first field effect transistor; The third terminal of the amplifying unit inputs a radio frequency signal, and the fourth terminal of the amplifying unit outputs the amplified radio frequency signal; The amplifying unit further includes: a first inductor, a second inductor, a third inductor, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor and a first resistor; The first field effect transistor has a gate connected to the first end of the amplifying unit and the first end of the second capacitor, a drain connected to the first end of the third inductor, and a source connected to the first end of the first capacitor, the first end of the second inductor, and the first end of the third capacitor; The second field effect transistor has a gate connected to the third end of the amplifying unit and the first end of the first resistor, a drain connected to the second end of the second inductor, the second end of the second capacitor and the first end of the fourth capacitor, and a source connected to ground through the first inductor; The second end of the third inductor is respectively connected to the second power supply end and the fourth end of the amplifying unit; the second end of the third capacitor and the second end of the fourth capacitor are both grounded; the second end of the first capacitor is respectively connected to the second end of the first resistor and the second end of the amplifying unit.

2. The amplifier according to claim 1, characterized in that The second bias unit includes: a third field effect transistor, a sixth resistor, a seventh resistor, an eighth resistor and a seventh capacitor; The third field effect transistor has a gate connected to the first end of the seventh resistor, the first end of the seventh capacitor and the first end of the eighth resistor, a drain connected to the second end of the seventh resistor and the first end of the sixth resistor, and a source connected to ground; The second end of the seventh capacitor is grounded; the second end of the eighth resistor is connected to the second end of the amplifying unit; and the second end of the sixth resistor is connected to the second power supply end.

3. The amplifier according to claim 2, characterized in that The third field effect transistor is a gallium arsenide-based enhancement mode pseudo-matched high electron mobility transistor.

4. The amplifier according to claim 1, characterized in that The second bias unit includes: a fourth field effect transistor, a fifth field effect transistor, a ninth resistor, a tenth resistor, an eighth capacitor and a ninth capacitor; The fourth field effect transistor has a gate connected to the first end of the ninth resistor, the first end of the eighth capacitor and the drain of the fifth field effect transistor, a drain connected to the second power supply terminal and the second end of the ninth resistor, and a source connected to the gate of the fifth field effect transistor, the first end of the ninth capacitor and the first end of the tenth resistor; The source of the fifth field effect transistor is grounded; the second end of the tenth resistor is connected to the second end of the amplifying unit; the second end of the eighth capacitor and the second end of the ninth capacitor are both grounded.

5. The amplifier according to claim 4, characterized in that The fourth field effect transistor and the fifth field effect transistor are both gallium arsenide-based enhancement-mode pseudo-matched high electron mobility transistors.

6. The amplifier according to claim 1, characterized in that The first bias unit includes: a fourth resistor and a fifth resistor; The fourth resistor has a first end connected to the first power supply end, and a second end connected to the first end of the fifth resistor and the first end of the amplification unit respectively; A second terminal of the fifth resistor is grounded.

7. The amplifier according to claim 1, characterized in that The first feedback unit includes: a second resistor, a third resistor, a fifth capacitor and a sixth capacitor; The fifth capacitor has a first end connected to the first end of the second resistor, and a second end connected to the first end of the third resistor and the second end of the first feedback unit respectively; The sixth capacitor has a first end connected to the second end of the third resistor and a second end connected to the ground; The second end of the second resistor is connected to the first end of the first feedback unit.

8. The amplifier according to any one of claims 1 to 7, characterized in that The first field effect transistor and the second field effect transistor are both gallium arsenide-based enhancement-mode pseudo-matched high electron mobility transistors.

9. A radio frequency integrated circuit, characterized in that: Comprising an amplifier as claimed in any one of claims 1 to 8.

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