Amplifier structure, amplifier bias circuit and chip module

Abstract

The invention provides an amplifier structure and an amplifier bias circuit. The amplifier structure comprises a main amplifier, a dummy tube, a current detection circuit and a bias control circuit, wherein the dummy tube and the main amplifier are arranged on the same crystal grain; the bias voltage of the dummy tube is the same as that of the main amplifier; the current detection circuit detects the static working current of the dummy tube and outputs a corresponding detection voltage signal to the bias control circuit according to the static working current; and the bias control circuit adjusts the bias voltage output to the main amplifier and the dummy tube according to the difference between the detection voltage signal and the reference voltage signal.

Description

Technical Field

[0001] The present application relates to the technical field of amplifiers, and in particular to an amplifier structure, an amplifier bias circuit and a chip module. Background Art

[0002] For HEMT (High Electron Mobility Transistor) devices, the conductive channel is formed by the two-dimensional electron gas (2DEG) at the heterojunction interface. Unlike MOS devices that rely solely on minority carriers in the inversion layer to form a conductive channel, the formation of 2DEG depends on the polarization effect at the heterojunction interface and the thickness and material composition of the barrier layer. Slight process or material changes (such as barrier thickness, Al component ratio) will significantly affect the 2DEG concentration, causing fluctuations in the threshold voltage (Vth).

[0003] For GaN HEMT, the spontaneous polarization and piezoelectric polarization effects of the material play a decisive role in the threshold voltage. These effects are highly sensitive to stress and thickness changes during the process, and can easily lead to significant Vth fluctuations. Vth may vary greatly between different wafers; even on the same wafer, different exposure areas (shot positions) may also have large deviations. Vth fluctuations can cause quiescent current fluctuations in the amplifier transistor. Quiescent current fluctuations may cause output power and linearity fluctuations in the amplifier (PA), thereby affecting the yield of the PA. Summary of the invention

[0004] In order to solve the existing technical problems, the present application provides an amplifier structure and an amplifier bias circuit that can ensure a stable static operating current.

[0005] In a first aspect, an embodiment of the present application provides an amplifier structure, comprising: a main amplifier, a dummy tube provided on the same die as the main amplifier, a current detection circuit, and a bias control circuit;

[0006] The bias voltage of the dummy tube is the same as that of the main amplifier;

[0007] The current detection circuit detects the static working current of the dummy tube, and outputs a corresponding detection voltage signal to the bias control circuit according to the static working current;

[0008] The bias control circuit adjusts the bias voltage output to the main amplifier and the dummy tube according to the difference between the detection voltage signal and the reference voltage signal.

[0009] In a second aspect, an amplifier bias circuit is provided, comprising:

[0010] A current detection circuit is used to detect the static working current of the dummy tube provided on the same die as the main amplifier, and output a corresponding detection voltage signal according to the static working current;

[0011] The bias control circuit obtains the detection voltage signal and the reference voltage signal, and adjusts the bias voltage output to the main amplifier and the dummy tube according to the difference between the detection voltage signal and the reference voltage signal.

[0012] In a third aspect, a chip module is provided, comprising the amplifier structure described in any embodiment of the present application.

[0013] The amplifier structure provided in the above embodiment, by setting a dummy tube located on the same die as the main amplifier, detects the static operating current of the dummy tube, and adjusts the bias voltage output to the main amplifier through a bias control circuit according to the corresponding detection voltage signal output according to the detected static operating current of the dummy tube and a reference voltage signal corresponding to the static operating current of a preset size. In this way, the static operating current of the dummy tube set on the same die as the main amplifier is not affected by the change of the size of the radio frequency signal, so as to provide a stable detection variable, and the bias voltage of the main amplifier is closed-loop adjusted by using the proportional relationship between the static operating current of the dummy tube and the static operating current of the main amplifier to ensure that the static operating current of the main amplifier can be a preset value, thereby achieving the purpose of stabilizing the static operating current of the main amplifier.

[0014] The amplifier bias circuit and chip module provided in the above embodiments belong to the same concept as the corresponding amplifier structure embodiments, and thus have the same technical effects as the corresponding amplifier structure embodiments, and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematic diagram of traditional amplifier biasing method.

[0016] Figure 2 for Figure 1 Schematic diagram of Vth distribution and static current distribution of a traditional amplifier biasing method.

[0017] Figure 3 FIG. 4 is a schematic diagram of an amplifier structure in an embodiment.

[0018] Figure 4 FIG. 4 is a circuit diagram of an amplifier structure in one embodiment.

[0019] Figure 5 FIG. 4 is a circuit diagram of a current detection circuit in an embodiment.

[0020] Figure 6 FIG. 4 is a circuit diagram of an amplifier structure in an embodiment.

[0021] Figure 7 FIG. 4 is a circuit diagram of an amplifier structure in another embodiment.

[0022] Figure 8 FIG. 4 is a circuit diagram of an amplifier structure in yet another embodiment.

[0023] Fig. 9 FIG. 4 is a circuit diagram of an amplifier structure in yet another embodiment.

[0024] Fig.10 Schematic diagram of a closed-loop regulation of a static operating current of a main amplifier by an amplifier structure in an embodiment. DETAILED DESCRIPTION

[0025] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments of the specification.

[0026] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings. The described embodiments should not be regarded as limiting the present application. All other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of this application.

[0027] In the following description, the expression "some embodiments" is involved, which describes a subset of all possible embodiments. It should be noted that "some embodiments" may be the same subset or different subsets of all possible embodiments, and may be combined with each other without conflict.

[0028] In the following description, the terms "first, second, third" involved are merely used to distinguish similar objects and do not represent a specific ordering of the objects. It can be understood that "first, second, third" can be interchanged with a specific order or sequence where permitted, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0029] In the study of how to improve the consistency of the amplifier, the inventors of the present application conducted the following research on the prior art.

[0030] like Figure 1 As shown in the figure, the biasing method of the traditional amplifier is used. The gate (or base) of the amplifier (PA) uses a fixed bias voltage, which is an open-loop control. Considering the material and process fluctuations, the threshold voltage value Vth of the gate (or base) of the transistor has a large fluctuation. There will be large fluctuations between different transistor grains (between dies), different wafers (between wafers), and different exposure areas (between shots). Figure 2As shown, the gate (or base) threshold voltage Vth of the transistor fluctuates greatly and is distributed relatively discretely, which causes the static operating current of the amplifier to fluctuate greatly, such as Figure 2 In the middle right figure, the current fluctuates between 5 and 22.5 mA, reaching a distribution of 4.5 times. The large difference in static operating current leads to large differences in the gain, power, and linearity of different PA individuals. If the threshold is tightened, a lot of yield will be lost.

[0031] It is necessary to strictly control the threshold voltage value Vth of PA and reduce the fluctuation of the threshold voltage value Vth, because the non-uniformity of the material itself, the polarization effect, and the heterojunction interface are very sensitive, and the implementation is very difficult. The technical idea proposed by the inventor of the present application is to perform a separate fine-tuning bias on the PA monomer, by setting the dummy tube and PA on the same die, using the dummy tube set in parallel with the PA, and the two use the same threshold voltage value Vth. Since the position between the dummy tube and the PA is close, the material and process of the transistor are the same, and thus the characteristics are also the same, and due to the analog device characteristics of the dummy tube, its static operating current can be unaffected by the RF input signal, so the static operating current of the dummy tube can be detected as the detection result of the static operating current of the PA, and the bias voltage to the PA is closed-loop adjusted according to the detected static operating current of the dummy tube and the reference voltage signal corresponding to the preset static operating current, to ensure that the static operating current of the PA monomer can be the preset value.

[0032] Please refer to Figure 3 and Figure 4 , is an amplifier structure provided by an embodiment of the present application, including a main amplifier 11, a dummy tube 12 arranged on the same die as the main amplifier 11, a current detection circuit 21 and a bias control circuit 22; the bias voltage Vreg of the dummy tube 12 is the same as that of the main amplifier 11; the current detection circuit 21 detects the static operating current Iq of the dummy tube 12, and outputs a corresponding detection voltage signal Vdet to the bias control circuit 22 according to the static operating current Iq; the bias control circuit 22 adjusts the bias voltage Vreg output to the main amplifier 11 and the dummy tube 12 according to the difference between the detection voltage signal Vdet and the reference voltage signal SET.

[0033] Among them, the dummy tube 12 is a tool for testing and debugging circuits, which simulates the behavior of components or signals in an actual circuit through virtual connections. The main function of the dummy tube 12 is to temporarily replace some missing or inconveniently obtained components in the actual circuit design in order to test and verify the system. The dummy tube 12 and the main amplifier 11 are arranged close to each other on the substrate of the same crystal grain. The materials, processes, etc. of the two are the same, so the characteristics of the two are also the same. The static operating current of the dummy tube can be detected as the detection result of the static operating current of the main amplifier 11.

[0034] In an optional example, under the conditions that the process and layout allow, the dummy tube 12 is arranged in the middle of the tube die of the main amplifier 11, so that it can be ensured that the dummy tube 12 and the main amplifier 11 have almost the same characteristics. In another optional example, the dummy tube 12 is arranged at the edge of the tube die of the main amplifier 11, and the distance between the dummy tube 12 and the edge of the tube die of the main amplifier 11 is between 10μm and 100μm.

[0035] The reference voltage signal SET may be preset based on the static operating current Iq that the corresponding main amplifier 11 is expected to reach.

[0036] The amplifier structure provided in the above embodiment is provided with a dummy tube 12 located on the same die as the main amplifier 11, and the static operating current Iq of the dummy tube 12 is detected. The bias control circuit 22 adjusts the bias voltage Vreg output to the main amplifier 11 according to the corresponding detection voltage signal Vdet output according to the detected static operating current Iq of the dummy tube 12, and the reference voltage signal SET corresponding to the static operating current of the preset size. In this way, the size of the static operating current Iq of the dummy tube 12 is not affected by the change of the size of the radio frequency signal RF, so as to provide a stable detection variable, and the proportional relationship between the static operating current Iq of the dummy tube 12 and the static operating current Iq of the main amplifier 11 is used to perform closed-loop adjustment on the bias voltage Vreg of the main amplifier 11, so as to ensure that the static operating current Iq of the main amplifier 11 can be a preset value, thereby achieving the purpose of stabilizing the static operating current Iq of the main amplifier 11.

[0037] See also Figure 3In some embodiments, the bias control circuit 22 includes a comparator 221; the positive phase input terminal and the negative phase input terminal of the comparator 221 are respectively connected to the reference voltage signal SET and the detection voltage signal Vdet, and the output terminal of the comparator 221 outputs the bias voltage Vreg. The comparator 221 calculates a voltage error signal based on the corresponding detection voltage signal Vdet determined based on the detected static working current Iq of the dummy tube 12 and the reference voltage signal SET corresponding to the static working current of the preset size, and adjusts and outputs the bias voltage Vreg according to the voltage error signal, so as to adjust the static working current Iq of the main amplifier 11 in real time to be the same as the expected static working current Iq.

[0038] In some embodiments, the bias control circuit 22 further includes a reference voltage setting branch 23 connected to the non-inverting input terminal of the comparator 221; the reference voltage setting branch 23 includes a current source Isource and a reference resistor Rset connected between the current source Isource and the electrode ground, and the non-inverting input terminal is connected to a first node 230 between the current source Isource and the reference resistor Rset. Among them, the current source Isource can be a constant current source, and the voltage value at the first node 230 can be adjusted by setting the resistance value of the reference resistor Rset in the reference voltage setting branch 23, that is, adjusting the value of the reference voltage signal SET input to the non-inverting input terminal of the comparator 221. It should be noted that by setting the size of the reference resistor Rset, the size of the reference voltage signal SET is adjusted accordingly, and then the reference voltage signal SET is used as a reference standard. According to the difference between the detection voltage signal Vdet determined based on the detected static operating current Iq of the dummy tube 12 and the reference voltage signal SET, the bias voltage Vreg output by the comparator 221 is closed-loop regulated, and the error between the bias voltage Vreg and the reference voltage signal SET is eliminated through closed-loop regulation, so as to eliminate the error between the static operating current Iq of the main amplifier 11 and the expected static operating current Iq. In this way, the reference resistor Rset ultimately affects the size of the static operating current Iq of the amplifier monomer, and the reference resistor Rset corresponds to the size of the static operating current Iq of the corresponding amplifier monomer.

[0039] In some embodiments, the reference voltage setting branch 23 further includes a current limiting resistor R1 connected to the non-inverting input terminal of the comparator 221, and a shunt resistor R2 connected between the second node between the current limiting resistor R1 and the non-inverting input terminal and the electrode ground. At the non-inverting input terminal of the comparator 221, the current limiting resistor R1 can limit the current to prevent the comparator 221 from being damaged by excessive current, and the setting of the current limiting resistor R1 and the shunt resistor R2 connected to the ground can form a shunt branch with the reference resistor Rset, thereby improving the stability of the input voltage at the non-inverting input terminal and reducing interference. Optionally, the reference voltage setting branch 23 also includes a protection resistor R3 and a jumper resistor R4 connected to the negative phase input terminal of the comparator 221, the protection resistor R3 is connected between the negative phase input terminal and the output terminal of the current detection circuit 21, and the jumper resistor R4 is connected between the negative phase input terminal and the output terminal of the comparator 221, wherein the protection resistor R3 can also limit the current and improve the voltage stability of the negative phase input terminal of the comparator 221, and the jumper resistor R4 can improve the circuit stability.

[0040] In some embodiments, the current detection circuit 21 includes a detection resistor Rdet; the dummy tube 12 and the main amplifier 11 are three-terminal transistors, respectively including a control terminal, a first terminal, and a second terminal. The control terminals of the dummy tube 12 and the main amplifier 11 are used to receive the bias voltage output by the bias control circuit 22, and the first terminal is connected to the electrode ground, and the detection resistor Rdet is connected between the second terminal of the dummy tube 12 and the second terminal of the main amplifier 11. Among them, the three-terminal transistor can be a HEMT device or a FET device. If the dummy tube 12 and the main amplifier 11 are HEMT devices, the control terminal refers to the gate terminal, the first terminal refers to the source terminal, and the second terminal refers to the drain terminal; if the dummy tube 12 and the main amplifier 11 are FET devices, the control terminal refers to the base, the first terminal refers to the base electrode, and the second terminal refers to the emitter.

[0041] In the embodiment of the present application, the dummy tube 12 and the main amplifier 11 are HEMT devices for illustration. However, it can be understood that all descriptions involving the gate terminal of the HEMT device can be equivalent to the base of the FET device, the description involving the source terminal of the HEMT device can be equivalent to the collector of the FET device, and the description involving the drain terminal of the HEMT device can be equivalent to the emitter of the FET device. The detection resistor Rdet is connected between the drain terminal of the dummy tube 12 and the drain terminal of the main amplifier 11. The detection resistor Rdet is set at the drain terminal of the dummy tube 12. The voltage across the detection resistor Rdet is collected by utilizing the characteristic that the current of the dummy tube 12 does not change with the radio frequency signal RF, so that the size of the static working current Iq output by the dummy tube 12 under the current input bias voltage Vreg can be determined, that is, the size of the current static working current Iq of the main amplifier 11.

[0042] Optional, see Figure 4 and Figure 5 The current detection circuit 21 further includes a comparison circuit 213, which includes a positive input terminal, a negative input terminal and an output terminal, wherein the positive input terminal and the negative input terminal are respectively connected to both ends of the detection resistor Rdet, and the output terminal of the comparison circuit 213 is connected to the input terminal of the detection voltage signal Vdet of the bias control circuit 22. Figure 5 In a specific example, the comparison circuit 213 may include a comparator, and the positive input terminal and the negative input terminal of the comparator correspond to the positive input terminal and the negative input terminal of the comparison circuit 213 respectively, and are respectively connected to the two ends of the detection resistor Rdet, so that what is detected between the positive input terminal and the negative input terminal of the comparator is the voltage difference across the detection resistor Rdet, and the voltage difference between the positive input terminal and the negative input terminal is calculated to be the detection voltage signal Vdet that can characterize the current static working current Iq of the dummy tube 12, and is output to the bias control circuit 22 through the output terminal.

[0043] It should be noted that, in the amplifier structure provided in the embodiment of the present application, the bias control circuit 22 and the current detection circuit 21 can be arranged on the same controller chip 20. In this way, the bias control circuit 22 and the current detection circuit 21 are specifically designed according to the expected stable static operating current Iq required by the main amplifier 11 to be tested, and are integrated on the same controller chip 20, thereby simplifying the connection between the main amplifier 11 and the bias control circuit 22 and the current detection circuit 21 during use.

[0044] Optionally, the bias control circuit 22 and the current detection circuit 21 may also have some circuit elements disposed outside the controller die 20. In an optional example, Figure 6The circuit components of the bias control circuit 22 and the current detection circuit 21 except the reference resistor Rset are all arranged on the same controller chip 20, and the controller chip 20 is provided with a pin for electrically connecting to the reference resistor Rset. The size of the reference resistor Rset can change the size of the reference voltage signal SET connected to the bias control circuit 22 accordingly. The difference between the size of the reference voltage signal SET and the detection voltage signal Vdet can change the bias voltage Vreg output by the bias control circuit 22 to the main amplifier 11 accordingly, thereby adjusting the static operating current Iq of the main amplifier 11. Therefore, the size of the reference resistor Rset can change the size of the stable static operating current Iq expected to be obtained by the corresponding main amplifier 11 accordingly. In this way, by setting the reference resistor Rset outside the controller chip 20, different reference resistors Rset connected to the bias control circuit 22 can be easily and directly replaced, so that the bias control circuit 22 and the current detection circuit 21 can adapt to the different sizes of static operating currents Iq expected to be achieved by the main amplifier 11, and adapt to the closed-loop adjustment of the bias voltages Vreg of different main amplifiers 11, so as to achieve the purpose of stabilizing the static operating current Iq of the main amplifier 11.

[0045] In another alternative example, Figure 7 As shown, the circuit components of the bias control circuit 22 and the current detection circuit 21 except the detection resistor Rdet are all arranged on the same controller die 20, and the controller die 20 is provided with a pin for electrically connecting to the detection resistor Rdet. The size of the detection resistor Rdet can change the size of the detection voltage signal Vdet connected to the bias control circuit 22 accordingly. The difference between the size of the detection voltage signal Vdet and the reference voltage signal SET can change the size of the bias voltage Vreg output by the bias control circuit 22 to the main amplifier 11 accordingly, thereby adjusting the static operating current Iq of the main amplifier 11. Therefore, the size of the detection resistor Rdet can change the size of the stable static operating current Iq expected to be obtained by the corresponding main amplifier 11 accordingly. In this way, by setting the detection resistor Rdet outside the controller chip 20, different detection resistors Rdet connected to the bias control circuit 22 can be conveniently and directly replaced, so that the bias control circuit 22 and the current detection circuit 21 can adapt to the different sizes of static operating currents Iq expected to be achieved by the main amplifier 11, and adapt to the closed-loop adjustment of the bias voltages Vreg of different main amplifiers 11, so as to achieve the purpose of stabilizing the static operating current Iq of the main amplifier 11.

[0046] Please refer again to Figure 4, the bias control circuit 22 and the current detection circuit 21 may be arranged in addition to the controller chip 20, and the circuit components except the detection resistor Rdet and the reference resistor Rset may also be arranged on the same controller core chip 20. In this way, it is convenient to flexibly select detection resistors Rdet and reference resistors Rset of different sizes for access according to the size of the expected stable static operating current Iq required by different main amplifiers 11 to be tested. In addition, it should be noted that the bias control circuit 22 and the current detection circuit 21 may also be arranged in whole or in part on the same main amplifier chip 10 as the main amplifier 11. In some embodiments, such as Figure 8 As shown, the bias control circuit 22 and the current detection circuit 21 are both arranged on the main amplifier tube die 10 where the main amplifier 11 is located. In this way, the bias control circuit 22 and the current detection circuit 21 are specifically designed according to the expected stable static working current Iq of the main amplifier 11 to be tested, and are integrated with the main amplifier 11 and arranged on the same main amplifier tube die 10; and the detection resistor Rdet or the reference resistor Rset is arranged in an off-chip implementation of the controller die 20, such as Fig. 9 As shown, the corresponding detection resistor Rdet or reference resistor Rset is disposed on the main amplifier chip 10 where the main amplifier 11 is located.

[0047] In order to have a more comprehensive understanding of the effect of the size of the detection resistor Rdet and the reference resistor Rset on the regulation of the static operating current Iq of the main amplifier 11, please refer to Figure 4 and Fig.10 , taking the dummy tube 12 connected in parallel with the main amplifier 11 as 1 / n of the main amplifier 11 as an example, the closed-loop regulation of the bias voltage Vreg of the main amplifier 11 is described:

[0048] Assume that the gate width of the main amplifier 11 is 1000 um, the gate width of the dummy tube 12 is 1000 / n um, and n is usually 5-200.

[0049] Reference resistance R set The corresponding relationship between the size of and the expected static operating current IqIq of the main amplifier 11 is shown in Formulas 1 to 5:

[0050]

[0051] Vdet= Rdet*Iq / n; (Formula 3)

[0052]

[0053] Among them, Isource Refers to the power flow, the current direction can be input or output. For depletion-mode HEMT (high electron mobility transistor), the gate (gate / base) bias is generally negative, so, Figure 3 The direction of Isource in can be reversed, that is, sink current. For enhancement-mode devices, such as enhancement-mode pHEMT (pseudomodulation doped heterojunction field effect transistor) or HBT (heterojunction bipolar transistor), the gate / base bias is positive, and Isource is the output current, that is, source current. R set refers to the reference resistor, R1 refers to the current limiting resistor, R2 refers to the shunt resistor, R3 refers to the protection resistor, R4 refers to the jumper resistor, V det Refers to the detection voltage signal, V reg is the bias voltage, R det It refers to the detection resistor, Iq refers to the size of the static working current Iq, n refers to the multiple ratio between the dummy tube 12 and the corresponding main amplifier 11, Vth refers to the threshold voltage value of the main amplifier 11, and k refers to the preset coefficient.

[0054] According to Formulas 1 to 5, by setting the value of the reference resistor Rset, the value of the static operating current Iq of the main amplifier 11 can be quantitatively determined according to the value of the currently connected detection resistor Rdet. set There is a one-to-one correspondence between the magnitude of the static operating current Iq of the main amplifier 11. Figure 6 Taking a closed-loop regulation as an example, if the actual static operating current Iq of the main amplifier 11 is too large, the current of the dummy tube 12 is too large. At this time, the detected detection voltage signal V det Too large, based on the detection voltage signal V det The difference between the reference voltage signal and the output bias voltage V reg Reduced, the quiescent operating current Iq of the main amplifier 11 is correspondingly controlled to be reduced, so that the reduced quiescent operating current Iq can be closer to the expected value. After multiple closed-loop adjustments, the quiescent operating current Iq of the main amplifier 11 can be adjusted to the expected value.

[0055] In some embodiments, the dummy tube 12 and the main amplifier 11 are arranged on the same main amplifier tube die 10 , so that it can be more accurately ensured that the threshold voltage values ​​of the dummy tube 12 and the main amplifier 11 are almost the same.

[0056] In some embodiments, in the amplifier structure, the control end of the dummy tube 12 is connected to the first feeding resistor R7, the control end of the main amplifier 11 is connected to the second feeding resistor R8, the other ends of the first feeding resistor R7 and the second feeding resistor R8 are connected, and are connected to the output end of the bias control circuit 22. Still taking the dummy tube 12 and the main amplifier 11 as HEMT devices as an example, the control end refers to the gate end, the gate ends of the dummy tube 12 and the main amplifier 11 are interconnected through the first feeding resistor R7 and the second feeding resistor R8, the dummy tube 12 and the main amplifier 11 are isolated through the feeding resistors, and the gate ends of the dummy tube 12 and the main amplifier 11 are connected to the output end of the bias control circuit 22 through the corresponding first feeding resistor R7 and the second feeding resistor R8, so as to ensure that the dummy tube 12 and the main amplifier 11 can be biased with the same DC potential. Optionally, the second end of the main amplifier 11 is connected to the power supply terminal VDD through the choke inductor L1, and the current detection circuit 21 is provided at the second end of the main amplifier 11 and the dummy tube 12 to detect the static working current of the dummy tube. Still taking the dummy tube 12 and the main amplifier 11 as HEMT devices as an example, the second end refers to the drain end of the dummy tube 12 and the main amplifier 11. It can be understood that an inductor can also be provided at the drain end of the dummy tube 12, which is connected to the power supply terminal VDD through the inductor, or connected to the drain end of the main amplifier 11 through the inductor to form an electrical node, and then connected to the power supply terminal VDD. For the main amplifier 11 and the dummy tube 12, both are isolated at the gate end and the drain end, which can avoid the influence of the radio frequency signal RF on the dummy tube 12. The dummy tube 12 only has a static working current Iq, and the magnitude of its static working current Iq does not change with the change of the RF signal. Based on the characteristic of the constant current, the dummy tube 12 can be used to achieve the purpose of real-time current detection of the main amplifier 11.

[0057] In some embodiments, the current source Isource may be a constant current source with temperature compensation, and the current source Isource may have a preset temperature coefficient, such as a thermistor that changes with temperature may be set in the current source Isource, and Isource is set to a positive temperature coefficient. That is, when the ambient temperature is high, the value of the corresponding current source Isource increases, and the static operating current Iq of the corresponding main amplifier 11 increases accordingly at high temperatures; conversely, when the ambient temperature is low, the value of the corresponding current source Isource decreases, and the static operating current Iq of the corresponding main amplifier 11 decreases accordingly at low temperatures, thereby achieving temperature compensation for the adjustment of the static operating current Iq of the main amplifier 11.

[0058] On the other hand, an embodiment of the present application further provides an amplifier bias circuit, which can be applied to the amplifier structure of the aforementioned embodiment.

[0059] Please refer again Figure 4 and Figure 5 In some embodiments, the amplifier bias circuit includes: a current detection circuit 21, which is used to detect the static operating current Iq of the dummy tube 12 arranged on the same die as the main amplifier 11, and output a corresponding detection voltage signal Vdet according to the static operating current Iq; a bias control circuit 22, which obtains the detection voltage signal Vdet and the reference voltage signal SET, and adjusts the bias voltage Vreg output to the main amplifier 11 and the dummy tube 12 according to the difference between the detection voltage signal Vdet and the reference voltage signal SET.

[0060] It can be understood that in the amplifier structure shown in the above embodiment, the bias control circuit 22 and the current detection circuit 21 for adjusting the static working current Iq of the main amplifier 11 can be formed as independent products relative to the main amplifier 11, that is, the amplifier bias circuit provided in the above embodiment. In practical applications, according to different main amplifiers 11, an amplifier bias circuit formed as an independent product that matches it can be selected and connected. The current detection circuit 21 detects the static working current Iq of the dummy tube 12 to generate and output the corresponding detection voltage signal Vdet. The bias control circuit 22 adjusts the bias voltage Vreg output to the main amplifier 11 according to the difference between the detection voltage signal Vdet and the reference voltage signal SET. The radio frequency signal RF is not coupled into the dummy tube 12. The dummy tube 12 is isolated from the control end (gate end) and the second end (drain end) of the main amplifier 11 by the feeding resistor and the choke inductor, respectively. In this way, the amplifier bias circuit provided in the embodiment of the present application utilizes the fact that the size of the static operating current Iq of the dummy tube 12 is not affected by the change in the size of the radio frequency signal RF to obtain a stable detection variable, and utilizes the proportional relationship between the static operating current Iq of the dummy tube 12 and the static operating current Iq of the main amplifier 11 to perform closed-loop adjustment on the bias voltage Vreg of the main amplifier 11 to ensure that the static operating current Iq of the main amplifier 11 can be a preset value, thereby achieving the purpose of stabilizing the static operating current Iq of the main amplifier 11.

[0061] Optionally, the bias control circuit 22 includes a comparator 221 and a reference voltage setting branch 23; the reference voltage setting branch 23 includes a current source Isource and a reference resistor Rset connected between the current source Isource and the electrode ground, the positive phase input terminal of the comparator 221 is connected to the first node 230 between the current source Isource and the reference resistor Rset; the negative phase input terminal of the comparator 221 is connected to the output terminal of the current detection circuit 21 to receive the detection voltage signal Vdet; the output terminal of the comparator 221 outputs the bias voltage Vreg. The reference voltage setting branch 23 can change the size of the bias voltage Vreg output to the main amplifier 11 accordingly by using the adjustable size of the reference resistor Rset, so as to adjust the size of the static operating current Iq of the main amplifier 11 to reach the expected size.

[0062] Optionally, the current detection circuit 21 includes a detection resistor Rdet and a comparison circuit 213; the detection resistor Rdet is used to connect to the drain end of the dummy tube 12 and the drain end of the main amplifier 11; the positive input end and the negative input end of the comparison circuit 213 are respectively connected to the two ends of the detection resistor Rdet, and the output end outputs the detection voltage signal Vdet. Among them, the current detection circuit 21 uses the adjustable size of the detection resistor Rdet to maintain a reasonable proportional relationship between the size of the detection resistor Rdet and the reference resistor Rset, ensuring the reliability and accuracy of the comparator 221 to perform closed-loop regulation on the output bias voltage Vreg based on the difference between the detection voltage signal Vdet and the reference voltage signal SET.

[0063] Optionally, the circuit components of the bias control circuit 22 and the current detection circuit 21, except for the reference resistor Rset, are all arranged on the same controller chip 20, and the controller chip 20 is provided with a pin for electrically connecting to the reference resistor Rset; and / or, the circuit components of the bias control circuit 22 and the current detection circuit 21, except for the detection resistor Rdet, are all arranged on the same controller chip 20, and the controller chip 20 is provided with a pin for electrically connecting to the detection resistor Rdet. By setting the reference resistor Rset, or the detection resistor Rdet, or the reference resistor Rset and the detection resistor Rdet outside the chip of the controller chip 20, the controller chip 20 correspondingly reserves a pin for the electrical connection of the connected detection resistor Rdet or reference resistor Rset. The pin can be designed as an electrical connection method that is easy to implement, such as plug-in, pasting during assembly, welding, etc. In actual application, the matching size of the detection resistor Rdet and the reference resistor Rset can be determined according to the expected size of the static operating current Iq required by the current main amplifier 11. Connect to the controller chip 20, in this way, it is convenient to directly replace the detection resistor Rdet or reference resistor Rset of different sizes connected to the bias control circuit 22, so that the bias control circuit 22 and the current detection circuit 21 can adapt to the different sizes of static operating current Iq expected to be achieved by the main amplifier 11, and adapt to the closed-loop adjustment of the bias voltage Vreg of different main amplifiers 11, so as to achieve the purpose of stabilizing the static operating current Iq of the main amplifier 11.

[0064] On the other hand, an embodiment of the present application further provides a chip module, comprising the amplifier structure described in any embodiment of the present application.

[0065] The amplifier structure may be that the current detection circuit 21 and the bias control circuit 22 may be integrally arranged on the controller chip 20, and the controller chip 20 and the main amplifier chip 10 where the main amplifier 11 is located are packaged to form a chip module; or, the amplifier structure may be that the current detection circuit 21 and the bias control circuit 22 are integrally arranged on the main amplifier chip 10 with the main amplifier 11, and then packaged to form a chip module; or, the amplifier structure may be that in the current detection circuit 21 and the bias control circuit 22, except for the reference resistor Rset and the detection resistor Rdet, all other circuit components are arranged On the controller chip 20, the controller chip 20 and the main amplifier chip 10 where the main amplifier 11 is located are packaged to form a chip module, and the chip module is provided with packaging pins for connecting the reference resistor Rset and the detection resistor Rdet; or, the amplifier structure can be a current detection circuit 21 and a bias control circuit 22, except for the reference resistor Rset and the detection resistor Rdet, other circuit components are arranged on the main amplifier chip 10 with the main amplifier 11, and then packaged to form a chip module, and the chip module is provided with packaging pins for connecting the reference resistor Rset and the detection resistor Rdet.

[0066] The amplifier structure and amplifier bias circuit provided in the above embodiments have at least the following characteristics:

[0067] First, the main amplifier 11 and the dummy tube 12 are connected in parallel and biased with the same potential. The main amplifier 11 and the dummy tube 12 are arranged on the same main amplifier tube crystal grain 10 (the same die), ensuring that the threshold voltage values ​​Vth of the two are almost the same.

[0068] Second, the amplifier bias circuit detects the static operating current Iq of the dummy tube 12 through the current detection circuit 21, and uses the bias control circuit 22 to determine the difference between the detection voltage signal Vdet and the reference voltage signal SET using the detected static operating current Iq of the dummy tube 12, to perform closed-loop adjustment on the bias voltage Vreg of the main amplifier 11 to ensure that the static operating current Iq of the main amplifier 11 can be stabilized at a preset value. In this way, compared with the method of directly detecting the operating current of the main amplifier 11 for adjustment, the influence of the current size of the main amplifier 11 following the size change of the radio frequency signal RF, resulting in inaccurate detection values, can be eliminated, not only can a more stable detection variable be obtained, but also the loss efficiency can be reduced.

[0069] Third, the gate / base bias of the main amplifier 11 and the dummy tube 12 are connected together through a feeding resistor, and the drain of the dummy tube 12 is isolated from the drain of the main amplifier 11 by a choke inductor L1, which can further avoid the influence of the radio frequency signal RF on the static operating current Iq in the dummy tube 12.

[0070] Fourth, the current detection resistor Rdet can be located outside the controller chip 20, or inside the controller chip 20, or inside the main amplifier chip 10 where the main amplifier 11 is located; a reference voltage setting branch 23 is set in the bias control circuit 22, so that the reference voltage signal SET connected to the comparator 221 can be set by the size of the reference resistor Rset in the reference voltage setting branch 23, and the size of the reference resistor Rset can preset the static operating current Iq of the main amplifier 11.

[0071] Fifth, in the reference voltage setting branch 23, the current source Isource can set a temperature coefficient and adapt to the ambient temperature for temperature compensation, which is beneficial to expanding the application range of the main amplifier 11. In various extremely high or low temperature application environments, the static operating current Iq of the main amplifier 11 can still be effectively adjusted to stabilize at the expected size, thereby improving product consistency.

[0072] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0073] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An amplifier structure, characterized in that: It includes a main amplifier, a dummy tube arranged on the same die as the main amplifier, a current detection circuit and a bias control circuit; The bias voltage of the dummy tube is the same as that of the main amplifier; The current detection circuit detects the static working current of the dummy tube, and outputs a corresponding detection voltage signal to the bias control circuit according to the static working current; The bias control circuit adjusts the bias voltage output to the main amplifier and the dummy tube according to the difference between the detection voltage signal and the reference voltage signal.

2. The amplifier structure according to claim 1, characterized in that: The bias control circuit comprises a comparator; a positive phase input terminal and a negative phase input terminal of the comparator are respectively connected to the reference voltage signal and the detection voltage signal, and an output terminal of the comparator outputs the bias voltage.

3. The amplifier structure according to claim 2, characterized in that: The bias control circuit also includes a reference voltage setting branch connected to the non-inverting input terminal of the comparator; the reference voltage setting branch includes a current source and a reference resistor connected between the current source and an electrode ground, and the non-inverting input terminal is connected to a first node between the current source and the reference resistor.

4. The amplifier structure according to claim 3, characterized in that: The reference voltage setting branch further includes a current limiting resistor connected to the non-inverting input terminal, and a shunt resistor connected between a second node between the current limiting resistor and the non-inverting input terminal and an electrode ground; and / or, The reference voltage setting branch also includes a protection resistor connected to the negative phase input terminal, and a jumper resistor connected between the negative phase input terminal and the output terminal; and / or, The current source is a constant current source with temperature compensation.

5. The amplifier structure according to claim 3, characterized in that: The current detection circuit includes a detection resistor; the dummy tube and the main amplifier are both three-terminal transistors, respectively including a control end, a first end and a second end, the control end is used to receive the bias voltage, the first end is connected to the electrode ground, and the detection resistor is connected between the second end of the dummy tube and the second end of the main amplifier.

6. The amplifier structure according to claim 5, characterized in that: The current detection circuit also includes a comparison circuit, which includes a positive input terminal, a negative input terminal and an output terminal, the positive input terminal and the negative input terminal are respectively connected to the two ends of the detection resistor, and the output terminal of the comparison circuit is connected to the input terminal of the detection voltage signal of the bias control circuit.

7. The amplifier structure according to claim 5, characterized in that: The bias control circuit and the current detection circuit are both arranged on the same controller die; and / or, The circuit components of the bias control circuit and the current detection circuit except the reference resistor are all arranged on the same controller die, and the controller die is provided with a pin for being electrically connected to the reference resistor; and / or, The bias control circuit and the circuit components of the current detection circuit except the detection resistor are all arranged on the same controller die, and the controller die is provided with a pin for being electrically connected to the detection resistor; and / or, In the bias control circuit and the current detection circuit, the detection resistor is arranged on the main amplifier tube crystal grain where the main amplifier is located, and other circuit components are arranged on the same controller crystal grain; and / or, The bias control circuit and the current detection circuit are arranged on the main amplifier tube die where the main amplifier is located; and / or, In the bias control circuit and the current detection circuit, except for the detection resistor and the reference resistor, other circuit components are arranged on the main amplifier tube crystal grain where the main amplifier is located.

8. The amplifier structure according to any one of claims 1 to 7, characterized in that The dummy tube and the main amplifier are both three-terminal transistors, respectively including a control terminal, a first terminal, and a second terminal; The control end of the dummy tube is connected to a first feeding resistor, the control end of the main amplifier is connected to a second feeding resistor, the other ends of the first feeding resistor and the second feeding resistor are connected, and are connected to the output end of the bias control circuit; and / or, the first ends of the dummy tube and the main amplifier are connected to an electrode ground, the second end of the main amplifier is connected to a power supply end through a choke inductor, and the current detection circuit is provided at the main amplifier and the second end of the dummy tube to detect the static operating current of the dummy tube.

9. An amplifier bias circuit, characterized in that: include: A current detection circuit is used to detect the static working current of the dummy tube provided on the same die as the main amplifier, and output a corresponding detection voltage signal according to the static working current; The bias control circuit obtains the detection voltage signal and the reference voltage signal, and adjusts the bias voltage output to the main amplifier and the dummy tube according to the difference between the detection voltage signal and the reference voltage signal.

10. The amplifier bias circuit according to claim 9, characterized in that: The bias control circuit includes a comparator and a reference voltage setting branch; The reference voltage setting branch includes a current source and a reference resistor connected between the current source and the electrode ground, and the non-inverting input terminal of the comparator is connected to a first node between the current source and the reference resistor; The negative phase input terminal of the comparator is connected to the output terminal of the current detection circuit to receive the detection voltage signal; The output terminal of the comparator outputs the bias voltage.

11. The amplifier bias circuit according to claim 10, characterized in that: The current detection circuit includes a detection resistor and a comparison circuit; The dummy tube and the main amplifier are both three-terminal transistors, respectively including a control end, a first end, and a second end, the control end is used to receive the bias voltage, the first end is connected to the electrode ground, and the detection resistor is used to connect to the second end of the dummy tube and the second end of the main amplifier; The positive input terminal and the negative input terminal of the comparison circuit are respectively connected to the two ends of the detection resistor, and the output terminal outputs the detection voltage signal.

12. The amplifier bias circuit according to claim 11, characterized in that: The circuit components of the bias control circuit and the current detection circuit except the reference resistor are all arranged on the same controller chip, and the controller chip is provided with a pin for electrically connecting to the reference resistor; and / or, The bias control circuit and the circuit components of the current detection circuit except the detection resistor are all arranged on the same controller die, and the controller die is provided with a pin for being electrically connected to the detection resistor; and / or, The bias control circuit and the current detection circuit are both arranged on the main amplifier tube crystal grain where the main amplifier is located.

13. A chip module, characterized in that: Comprising the amplifier structure as claimed in any one of claims 1 to 8.

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