Amplifier and fully differential buffer

Abstract

The invention provides an amplifier and a fully differential buffer, the amplifier comprises a fully differential amplification module and a driving module, the input end of the fully differential amplification module receives an input differential signal, and the output end of the fully differential amplification module is connected with the input end of the driving module; the fully differential amplification module is used for inputting a differential signal to generate a differential output signal; the driving module is used for outputting differential driving signals with different driving magnitudes according to the differential output signals, the differential driving signals with different driving magnitudes can be output through one circuit according to the driving requirements in different scenes, flexible adjustment of the driving magnitudes of the output signals of the amplifier is achieved, and the circuit design is simplified.

Description

Technical Field

[0001] The present invention relates to the technical field of integrated circuits, and in particular to an amplifier and a fully differential buffer. Background Art

[0002] In current interface circuits, to meet the needs of multiple operating modes, a fully differential buffer typically requires a circuit that supports switching between multiple modes. Because different operating modes have different requirements for the circuit's output amplitude and drive capability, existing design methods often design a specific buffer for each mode.

[0003] When multiple operating modes need to be supported, since each mode requires an independent buffer, multiple different buffers need to be developed accordingly. This not only increases the complexity of circuit design, but also leads to an expansion of circuit space, which has an adverse impact on circuit performance and reliability.

[0004] Therefore, an amplifier and a fully differential buffer are urgently needed to solve the above problems. Summary of the Invention

[0005] In response to the problems existing in the prior art, the present invention provides an amplifier and a fully differential buffer, which can output differential drive signals of multiple different drive sizes through a single circuit, thereby achieving switching of drive capabilities under different modes.

[0006] The present invention provides an amplifier, comprising a fully differential amplifying module and a driving module, wherein an input end of the fully differential amplifying module receives an input differential signal, and an output end of the fully differential amplifying module is connected to an input end of the driving module; The fully differential amplification module is configured to generate a differential output signal according to the input differential signal; The driving module is used to output differential driving signals with different driving magnitudes according to the differential output signal.

[0007] According to an amplifier provided by the present invention, the driving module includes a first driving output circuit and a second driving output circuit, the control end of the first driving output circuit is connected to a differential output end of the fully differential amplifying module, and the control end of the second driving output circuit is connected to the other differential output end of the fully differential amplifying module; The i-th driving output circuit is used to output an i-th driving signal with different driving magnitudes according to the received differential output signal; wherein, i is one or two, and the first driving signal and the second driving signal are differential signals.

[0008] According to an amplifier provided by the present invention, the first drive output circuit includes N positive-phase drive units, and the second drive output circuit includes M negative-phase drive units; The control end of the positive phase driving unit is connected to the one differential output end of the fully differential amplifying module, and the control end of the negative phase driving unit is connected to the other differential output end of the fully differential amplifying module; The i-th driving output circuit is specifically used to control at least one of the positive phase driving units or at least one of the negative phase driving units to be turned on to output the i-th driving signal with different driving magnitudes; wherein N and M are both natural numbers not less than 1.

[0009] According to an amplifier provided by the present invention, the positive phase driving unit and the negative phase driving unit corresponding to the positive phase driving unit each include a control unit and a switch pair, wherein the control end of the switch pair is connected to the output end of the control unit; The control unit is used to generate a control signal; The switch pair is configured to be turned on or off under the action of the control signal and output the first drive signal and / or the second drive signal.

[0010] According to an amplifier provided by the present invention, the control unit includes a plurality of switches, and the control unit is specifically configured to generate corresponding control signals according to the conduction states of the switches to control the conduction or shutoff of the switches.

[0011] According to an amplifier provided by the present invention, the control unit includes a first switch and a second switch, and the closed states of the first switch and the second switch are opposite to each other to generate the control signal.

[0012] According to an amplifier provided by the present invention, the control unit includes a first sub-control unit and a second sub-control unit, the first sub-control unit and the second sub-control unit each include the first switch and the second switch, and the switch pair includes a PMOS transistor and an NMOS transistor; The source terminal of the PMOS transistor and one end of the first switch in the first sub-control unit are both connected to a first voltage, and the gate terminal of the PMOS transistor is connected to the other end of the first switch in the first sub-control unit and one end of the second switch in the first sub-control unit; The source terminal of the NMOS transistor and one end of the first switch in the second sub-control unit are both connected to the second voltage, and the gate terminal of the NMOS transistor is connected to the other end of the first switch in the second sub-control unit and one end of the second switch in the second sub-control unit; The other end of the second switch in the first sub-control unit and the second sub-control unit is connected to the differential output end of the fully differential amplifier module, the drain end of the PMOS tube is connected to the drain end of the NMOS tube, and the first voltage is higher than the second voltage.

[0013] According to an amplifier provided by the present invention, the other end of the second switch in the first sub-control unit and the second sub-control unit in the positive phase driving unit is connected to the differential output end of the fully differential amplifying module; The other ends of the second switches in the first sub-control unit and the second sub-control unit in the inverting driving unit are connected to the other differential output end of the fully differential amplifying module.

[0014] The present invention also provides a fully differential buffer, comprising a gain amplification module and the above-mentioned amplifier, wherein the input end of the gain adjustment module is connected to the output end of the amplifier, and the output end of the gain adjustment module is connected to the input end of the amplifier; The gain module is used to adjust the gain of the buffer and perform gain adjustment on the differential driving signal output by the amplifier according to the gain.

[0015] According to the fully differential buffer provided by the present invention, the gain adjustment module includes a gain adjustment path, and the output end of the amplifier is connected to the input end of the amplifier through the gain adjustment path; The gain module is specifically configured to switch on the gain adjustment path to adjust the gain of the buffer.

[0016] According to the fully differential buffer provided by the present invention, the gain adjustment path includes an adjustment load and a gain adjustment switch; The gain adjustment switch is used to control the size of the adjustment load included in the gain adjustment path to adjust the gain of the buffer.

[0017] The amplifier and fully differential buffer provided by the present invention are composed of a fully differential amplifier module and a driver module. The fully differential amplifier module receives an input differential signal and generates two sets of differential output signals. The driver module outputs differential drive signals of different drive sizes according to the input differential signal, thereby simplifying the circuit design. The present invention can output differential drive signals of multiple different drive sizes through a single circuit to meet the driving requirements in different scenarios, thereby achieving flexible adjustment of the drive size of the amplifier output signal and simplifying the circuit design. At the same time, the gain of the fully differential buffer is further adjusted through the gain module to meet the requirements for the buffer output amplitude in different scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the present invention or the prior art, 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 some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 A schematic diagram of the overall structure of the amplifier provided by the present invention; Figure 2 A schematic diagram of the specific structure of the amplifier provided by the present invention; Figure 3 A schematic diagram of the internal structure of the amplifier provided by the present invention; Figure 4 This is a structural diagram of the fully differential buffer circuit provided by the present invention. DETAILED DESCRIPTION

[0020] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0021] Figure 1 Schematic diagram of the overall structure of the amplifier provided by the present invention, the amplifier includes a fully differential amplifier module 10 and a driving module 11, the input end of the fully differential amplifier module 10 receives an input differential signal, and the output end of the fully differential amplifier module 10 is connected to the input end 11 of the driving module; The fully differential amplification module 10 is configured to generate a differential output signal according to the input differential signal; The driving module 11 is configured to output differential driving signals of different driving magnitudes according to the differential output signal.

[0022] In the present invention, the amplifier consists of two main modules: a fully differential amplifier module 10 and a driver module 11. The fully differential amplifier module 10 serves as the front end for signal processing, with its input receiving a differential signal. Differential signals are a special form of signal with advantages such as strong anti-interference capabilities. The fully differential amplifier module 10 processes the received differential input signal and generates two sets of differential output signals. These two sets of signals have a specific relationship in terms of amplitude and phase to meet the requirements of subsequent circuits.

[0023] Subsequently, the output of the fully differential amplifier module 10 is connected to the input of the driver module 11, transmitting the two sets of differential output signals generated to the driver module 11. The main function of the driver module 11 is to output differential drive signals with different drive magnitudes based on the two sets of differential output signals received. In the present invention, different drive magnitudes can be used to adapt to different load requirements or signal transmission distances. By adjusting the parameters or configuration of the driver module, it is possible to output differential drive signals with a variety of different drive magnitudes, thereby meeting the driving requirements of different application scenarios.

[0024] The amplifier provided by the present invention is composed of a fully differential amplifier module and a driving module. The fully differential amplifier module receives an input differential signal and generates two sets of differential output signals. The driving module outputs differential drive signals of different drive sizes based on the received signals. This simplifies the amplifier circuit design, enables flexible adjustment of multiple drive modes, and outputs differential drive signals of corresponding drive sizes for different drive modes, meeting the driving capability requirements for differential drive signals in different scenarios.

[0025] Figure 2 This is a schematic diagram of the specific structure of the amplifier provided by the present invention. Based on the above embodiment, the driving module includes a first driving output circuit 20 and a second driving output circuit 21. The control end of the first driving output circuit 20 is connected to a differential output end of the fully differential amplification module, and the control end of the second driving output circuit 21 is connected to the other differential output end of the fully differential amplification module. The i-th driving output circuit is used to output an i-th driving signal with different driving magnitudes according to the received differential output signal; wherein, i is one or two, and the first driving signal and the second driving signal are differential signals.

[0026] In the present invention, the drive module includes a first drive output circuit 20 and a second drive output circuit 21. The first drive output circuit 20 is configured to output a first drive signal of different drive magnitudes based on a set of received differential output signals, and the first drive output circuit 21 is configured to output a second drive signal of different drive magnitudes based on another set of received differential output signals. In the present invention, by providing two drive output circuits in the drive module, the drive output circuits output drive signals of different drive magnitudes based on the differential output signals they receive, and the drive signals output by the two drive output circuits are differential drive signals. It should be noted that the terms "first" and "second" are used only to distinguish the types of drive output circuits or drive signals and do not indicate their number.

[0027] On the other hand, the first drive output circuit 20 includes N positive phase drive units, and the second drive output circuit 21 includes M negative phase drive units; The control end of the positive phase driving unit is connected to the one differential output end of the full differential amplification module, and the control end of the negative phase driving unit is connected to the other differential output end of the full differential amplification module; The i-th driving output circuit is specifically used to control at least one positive phase driving unit or at least one negative phase driving unit to be turned on to output the i-th driving signal with different driving magnitudes; wherein N and M are both natural numbers not less than 1.

[0028] In the present invention, to achieve flexible and diverse differential drive signal outputs to meet the driving capability requirements of different loads or application scenarios, the drive module adopts an architecture based on a combination of positive-phase and negative-phase drive units. By providing N positive-phase drive units and M negative-phase drive units, and utilizing their connection to different differential output terminals of an amplifier, signals of varying drive magnitudes are generated under the influence of the differential output signals of the amplifier. These signals are then combined to form a differential drive signal that meets the requirements. This improves the drive flexibility and adaptability of the amplifier, enabling it to better cope with complex and changing practical application environments. A first drive output circuit comprises N (N is a natural number greater than or equal to 1) positive-phase drive units, and a second drive output circuit comprises M (M is a natural number greater than or equal to 1) negative-phase drive units. N and M can be the same or different, and this embodiment does not impose any restrictions on this. The drive signals output by the first and second drive output circuits are differential signals.

[0029] Specifically, the first drive output circuit 20 is used to control at least one positive phase drive unit to be turned on to output a first drive signal of different drive sizes, and the second drive output circuit 21 is used to control at least one negative phase drive unit to be turned on to output a second drive signal of different drive sizes, wherein the drive sizes of the first drive signal and the second drive signal are the same, and the drive sizes of the drive signals generated between each positive phase drive unit or between each negative phase drive unit are different from each other, or when N and M are both natural numbers greater than 1, there are at least two positive phase drive units with different drive sizes between the N positive phase drive units, and there are at least two negative phase drive units with different drive sizes between the M negative phase drive units. Therefore, the first drive output circuit 20 can output first drive signals of different drive sizes by controlling the number of positive-phase drive units that are turned on, or can output first drive signals of different drive sizes by controlling different positive-phase drive units that are turned on. Correspondingly, the second drive output circuit 21 can output second drive signals of different drive sizes by controlling the number of negative-phase units that are turned on, or can output second drive signals of different drive sizes by controlling different negative-phase drive units that are turned on. It should be noted that in each process of generating differential drive signals through the first drive output circuit 20 and the second drive output circuit 21, the number of positive-phase drive units that are turned on and the number of negative-phase drive units that are turned on are not required to be the same, as long as the drive signals output by the first drive output circuit 20 and the second drive output circuit 21 are differential signals.

[0030] Exemplarily, the control end of the positive phase drive unit is connected to a differential output end of the fully differential amplifier module, the control end of the negative phase drive unit is connected to another differential output end of the fully differential amplifier module, the high voltage power supply ends of the positive phase drive unit and the negative phase drive unit are connected to the first voltage, and the low voltage power supply ends of the positive phase drive unit and the negative phase drive unit are connected to the second voltage; the positive phase drive unit is used to turn on and output the first drive signal under the action of a set of differential output signals received, and to turn off under the action of the first voltage and the second voltage; the negative phase drive unit is used to turn on and output the second drive signal under the action of another set of differential output signals received, and to turn off under the action of the first voltage and the second voltage.

[0031] That is, the first drive output circuit 20 can conduct the connection between the control end of at least one positive phase drive unit and a set of differential output ends of the amplifier. When this connection is conducted, a set of differential output signals output by the set of differential output ends of the amplifier will be transmitted to the positive phase drive unit to control the conduction of the positive phase unit. When the first drive output circuit 20 conducts the connection between the control end of at least one positive phase drive unit and the first voltage and the second voltage, if the first voltage is high and the second voltage is low, the positive phase drive unit is turned off under the action of the first voltage and the second voltage; it should be noted that when the first voltage is less than or equal to the voltage of the negative phase output signal in the differential output signal, and when the second voltage is greater than or equal to the voltage of the positive phase output signal in the differential output signal, the positive phase drive unit can also be turned on under the action of the first voltage and the second voltage. The conduction and shutdown principles of the negative phase drive unit are the same as those of the positive phase drive unit, except that the control end of the negative phase drive unit receives another set of differential output signals output by the fully differential amplifier module.

[0032] When the positive-phase drive unit or the negative-phase drive unit is turned on, the drive unit processes and amplifies the input signal to varying degrees, thereby outputting a first drive signal or a second drive signal of varying drive magnitudes. The drive output circuit includes multiple positive-phase drive units and negative-phase drive units. Each positive-phase drive unit or negative-phase drive unit can generate signals of varying drive magnitudes by setting different circuit parameters within the unit (such as transistor size, resistance value, etc.). By providing multiple positive-phase drive units and multiple negative-phase drive units, this embodiment ensures that signals with opposite phases but matching drive characteristics can be subsequently generated, laying the foundation for the formation of differential drive signals.

[0033] In the present invention, the first drive signal output by the first drive output circuit 20 and the second drive signal output by the second drive output circuit 21 together constitute a differential drive signal. This differential drive signal has advantages such as strong anti-interference ability and the ability to better drive the load. In practical applications, according to the characteristics of the load or system requirements, appropriate positive-phase drive units and negative-phase drive units can be selected for combination or turned on to output a differential drive signal that meets specific drive magnitudes and characteristics.

[0034] Based on the above embodiments, the positive phase drive unit and the positive phase drive unit pair include a control unit and a switch pair tube, the control end of the switch pair tube is connected to the output end of the control unit; the control unit is used to generate a control signal; the switch pair tube is used to turn on or off under the action of the control signal and output the first drive signal and / or the second drive signal.

[0035] In the present invention, the driving capabilities of the switch pairs in different positive-phase drive units or each negative-phase drive unit are different from each other, or when N and M are both natural numbers greater than 1, the driving capabilities of the switch pairs between at least two positive-phase drive units among the N positive-phase drive units are different from each other, and the driving capabilities of the switch pairs between at least two positive-phase drive units among the M negative-phase drive units are different from each other. Driving capability refers to the characteristics such as the current that can pass through the switch pair when it is turned on and the strength of the output signal. This difference can be achieved in many ways, such as different types of transistors used in the switch pair, different sizes of transistors (such as channel length, width), or different internal circuit connection methods. Different driving capabilities enable each drive unit to provide appropriate driving strength when facing different load requirements.

[0036] The positive-phase drive unit and the negative-phase drive unit in the present invention both include a control unit and a switch pair tube. The control unit is used to generate a control signal to control the conduction state of the switch pair tube. The switch pair tube in the positive-phase drive unit is turned on or off according to the control signal output by the control unit in the positive-phase drive unit, and outputs a first drive signal. The switch pair tube in the negative-phase drive unit is turned on or off according to the control signal output by the control unit in the negative-phase drive unit, and outputs a second drive signal.

[0037] The control unit plays a central role in the entire driver unit. It receives a drive regulation control signal, which can come from an external control circuit or a signal automatically generated within the system based on load conditions. Based on this signal, the control unit further generates a control signal to turn the corresponding switch pair on or off. Conversely, when the drive regulation control signal indicates that the driver unit is no longer required, the control unit generates a control signal to turn the switch pair off. At this point, current cannot flow through the switch pair, and the driver unit is in the off state, outputting no drive signal. This approach allows for flexible control of the operating state of each driver unit, enabling precise adjustment of the amplifier's output drive signal to suit diverse application scenarios and load requirements.

[0038] On the basis of the above embodiment, the control unit includes a plurality of switches, and the control unit is specifically used to generate corresponding control signals according to the conduction states of the switches to control the switches to turn on or off the tubes.

[0039] Specifically, the control unit includes a plurality of switches. The control unit can generate corresponding control signals according to the conduction state of the switches to control the conduction or shutoff of the switch pairs. For example, when some of the switches are on and others are off, a first control signal is generated to control the conduction of the corresponding switch pairs to turn on the corresponding positive-phase drive unit or negative-phase drive unit. When the conduction or shutoff state of each of the switches changes, a second control signal is generated. The switch pairs are shut off according to the received second control signal, and the corresponding positive-phase drive unit or negative-phase drive unit is shut off. The present invention controls the conduction state of each positive-phase drive unit and negative-phase drive unit through the cooperation of the control unit and the switch pairs to generate differential drive signals of different drive magnitudes.

[0040] Based on the above embodiment, the control unit includes a first switch and a second switch, and the closed states of the first switch and the second switch are opposite to each other to generate the control signal.

[0041] Specifically, the control unit includes a first switch and a second switch, the closed states of the first switch and the second switch are opposite, and the control unit generates a corresponding control signal to control the conductive state of the switch pair tube according to the conductive state of the first switch and the second switch.

[0042] Figure 3 This is a schematic diagram of the internal structure of the amplifier provided by the present invention. Based on the above embodiment, the control unit includes a first sub-control unit 301 and a second sub-control unit 302. The first sub-control unit 301 and the second sub-control unit 302 each include a first switch and a second switch. The switch pair includes a PMOS transistor and an NMOS transistor. The source terminal of the PMOS transistor and one end of the first switch in the first sub-control unit 301 are both connected to the first voltage, and the gate terminal of the PMOS transistor is connected to the other end of the first switch in the first sub-control unit 301 and one end of the second switch in the first sub-control unit 301; The source terminal of the NMOS transistor and one end of the first switch in the second sub-control unit 302 are both connected to the second voltage, and the gate terminal of the NMOS transistor is connected to the other end of the first switch in the second sub-control unit 302 and one end of the second switch in the second sub-control unit 302; The other end of the second switch in the first sub-control unit 301 and the second sub-control unit 302 is connected to the differential output end of the fully differential amplifier module, the drain end of the PMOS tube is connected to the drain end of the NMOS tube, and the first voltage is higher than the second voltage.

[0043] The other end of the second switch in the first sub-control unit and the second sub-control unit in the positive phase driving unit is connected to a differential output end of the fully differential amplifier module; the other end of the second switch in the first sub-control unit and the second sub-control unit in the negative phase driving unit is connected to another differential output end of the fully differential amplifier module.

[0044] In the present invention, for the control units in the positive phase drive unit and the negative phase drive unit, the control units include a first sub-control unit and a second sub-control unit. It should be noted that the first sub-control unit in the positive phase drive unit and the negative phase drive unit are both connected to the first voltage, and the second sub-control unit is both connected to the second voltage; the first sub-control unit and the second sub-control unit in the positive phase drive unit and the negative phase drive unit both include a first switch and a second switch, and the switch pair tubes in the positive phase drive unit and the negative phase drive unit include a PMOS tube and an NMOS tube. The present invention realizes precise control of the working state of the switch pair tubes in the positive phase drive unit and the negative phase drive unit through the connection between the switch pair tubes, the control unit and the output end of the differential amplifier module, the first voltage and the second voltage, thereby generating a drive signal that meets specific requirements.

[0045] Figure 4 A schematic diagram of the structure of the fully differential buffer provided by the present invention is shown in FIG. Figure 4 As shown, the fully differential buffer provided by the present invention includes a gain module 401 and the amplifier 402 described in the above embodiments, the input end of the gain module is connected to the output end of the amplifier, and the output end of the gain module is connected to the input end of the amplifier; The gain module is used to adjust the gain of the buffer and perform gain adjustment on the differential drive signal output by the amplifier according to the gain.

[0046] In the present invention, the input of the gain module is connected to the output of the amplifier, allowing the differential drive signal generated by the amplifier to be directly transmitted to the gain module. The differential drive signal typically consists of a positive-phase component and a negative-phase component (i.e., a first drive signal and a second drive signal). These components have specific amplitude, phase, and frequency characteristics that reflect the drive capability of the input differential signal after being processed by the amplifier.

[0047] The output of the gain module is connected to the input of the amplifier. This connection allows the signal processed by the gain module to be fed back into the amplifier, forming a feedback loop. The gain module further adjusts the gain of the amplifier output, amplifies the differential drive signal, and then inputs the amplified differential drive signal into the amplifier. Through continuous feedback and adjustment, the fully differential buffer can output a differential drive signal with stable gain and good characteristics, improving the stability of the entire buffer, reducing distortion, and meeting the signal buffering and amplification requirements of various electronic devices. It should be noted that one of the core functions of the gain module is to adjust the gain of the fully differential buffer. Gain refers to the ratio of the output signal amplitude to the input signal amplitude, which determines the degree of signal amplification of the buffer. The present application can flexibly adjust the buffer gain by changing the circuit parameters (such as resistance and capacitance values) within the gain module to adapt to different application scenarios and load requirements. For example, in situations where high-precision signal amplification is required, the gain of the fully differential buffer can be set to a larger value through the gain module; in situations where the signal amplitude requirement is not high, the gain of the fully differential buffer can be appropriately reduced through the gain module to reduce power consumption and noise.

[0048] Based on the above embodiment, the gain module includes a gain adjustment path, and the output end of the amplifier is connected to the input end of the amplifier through the gain adjustment path; The gain module is specifically configured to switch on the gain adjustment path to adjust the gain of the buffer.

[0049] like Figure 4 As shown, the gain module includes a first gain module 4011 and a second gain module 4012. The first gain adjustment module 4011 and the second gain adjustment module 4012 each include N gain adjustment paths. The output of the amplifier is connected to the input of the amplifier via the gain adjustment paths. The i-th gain module (i is 1 or 2) is specifically configured to switch between gain adjustment paths to adjust the gain of the buffer, further adjust the i-th drive signal based on the gain, and output the adjusted i-th drive signal to the amplifier. The N gain adjustment paths correspond to N different gains, indicating that each gain module offers multiple gain adjustment options. For example, when N = 3, the first gain module has three gain adjustment paths, corresponding to low gain, medium gain, and high gain; the second gain module also has three gain adjustment paths, corresponding to low gain, medium gain, and high gain. This design enables the buffer to flexibly select the appropriate gain to adjust the differential drive signal output by the amplifier according to different application scenarios and load requirements.

[0050] In the present invention, the amplifier output is connected to the amplifier input via these gain adjustment paths, forming a feedback loop. Through different gain adjustment paths, the differential drive signal output by the amplifier can be amplified with different gains and then fed back to the amplifier input, further amplifying the amplitude of the differential drive signal output by the buffer.

[0051] In the present invention, the i-th gain adjustment module can switch between different gain adjustment paths. For example, when a higher gain is required, the i-th gain adjustment module switches on the gain adjustment path corresponding to the higher gain; when a lower gain is required, the i-th gain adjustment module switches on the gain adjustment path corresponding to the lower gain. This switching can be achieved using an electronic switch (such as a transistor switch), which selects different gain adjustment paths by controlling the on and off state of the switch. By switching between different gain adjustment paths, the i-th gain module can adjust the gain of the buffer to different values. This gain adjustment further affects the drive level of the i-th drive signal. For example, when the gain increases, the amplitude of the i-th drive signal increases accordingly; when the gain decreases, the amplitude of the i-th drive signal decreases.

[0052] Based on the above embodiment, the gain adjustment path includes an adjustment load and a gain adjustment switch; The gain adjustment switch is used to control the size of the adjustment load included in the gain adjustment path to adjust the gain of the buffer.

[0053] Specifically, the first gain module and the second gain module also include multiple adjustment loads respectively, and any gain adjustment path includes at least one gain adjustment switch, which is used to control the number of adjustment loads contained in the corresponding gain adjustment path to adjust the gain of the buffer; wherein the number of adjustment loads on any two gain adjustment paths is different, so that different gain adjustment paths correspond to gains of different sizes.

[0054] Because the number of regulated loads in any two gain adjustment paths differs, the equivalent resistance of the gain adjustment path changes when the gain adjustment switch switches between them. According to circuit principles, in an amplifier circuit, the gain is related to the equivalent resistance of the feedback load (here, the regulated load in the gain adjustment path). When the equivalent resistance of the feedback load changes, the feedback amount also changes accordingly, enabling precise adjustment of the buffer gain.

[0055] In the present invention, Figure 3 and Figure 4As shown, the first output terminal of the amplifier outputs OUTP (a first drive signal), and the second output terminal of the amplifier outputs OUTN (a second drive signal). VIP and VIN are the initial differential input signals of the differential buffer. The first input terminal of the amplifier receives VIP, and the second input terminal of the amplifier receives VIN. The gain module includes two gain adjustment paths. The gain module controls the size of the adjustment load included in the gain adjustment path by turning on and off switches S0 and S1, thereby preseting the gain adjustment value of the fully differential buffer to match the needs of different gain modes. In addition, the closing states of switches S0 and S1 are opposite, that is, when S0 is closed, S1 must be open; conversely, when S1 is open, S0 is closed. This opposite switching state ensures that the circuit can operate correctly in different modes.

[0056] Specifically, in the present invention, when the switch S0 is closed and the switch S1 is open, OUTP=VIP, OUTN=VIN, that is, the gain AV0 of the fully differential buffer=(OUTP-OUTN) / (VIP-VIN)=1. At this time, the signal OUTP outputted from the first output terminal is equal to the signal VIP inputted from the first input terminal, and the signal OUTN outputted from the second output terminal is equal to the signal VIN inputted from the second input terminal, indicating that the input signals are transmitted to the output terminals with equal amplitude without gain or attenuation.

[0057] When the preset gain mode is adjusted to close switch S1 and open switch S0, based on the virtual short (equal input potential) and virtual open (zero input current) characteristics of the differential circuit, it can be deduced that OUTP = [(R1 + R0) / R0] × VIP, OUTN = [(R1 + R0) / R0] × VIN. At this time, the full differential gain AV1 = (OUTP - OUTN) / (VIP - VIN) = (R1 + R0) / R0, indicating that the input signal is amplified by (R1 + R0) / R0 times.

[0058] In the present invention, the resistance of the load can be adjusted by the gain module 401, such as Figure 4 The resistance values ​​of the load R0 and the load R1 are adjusted to achieve different gain adjustments. Furthermore, multiple sets of gain adjustment switches and corresponding adjustment load combinations can be introduced to construct more gain modes ( Figure 4 The gain in each gain mode can be freely designed according to specific needs, which greatly enhances the versatility and flexibility of the circuit, allowing the circuit to adapt to different application scenarios and achieve precise gain control.

[0059] Furthermore, amplifier 402 utilizes MOS transistors of varying sizes as core components of its driver stage. The dimensions of these MOS transistors (referring to their aspect ratio) directly impact the amplifier's output drive capability, which in turn affects the drive capability of the fully differential buffer. By designing the dimensions of these MOS transistors, the present invention enables amplifier 402 to output differential drive signals of varying magnitudes, thereby enabling multiple drive capability adjustments without increasing circuit area. This not only saves circuit area but also effectively reduces production costs.

[0060] The fully differential buffer provided by the present invention generates differential drive signals of different drive sizes according to the differential input signal by constructing a gain module and an amplifier, and further performs gain adjustment on the differential drive signal to amplify the amplitude of the differential drive signal, thereby meeting the circuit requirements for different output amplitudes and different drive capabilities, realizing flexible adjustment of multiple drive sizes and gain sizes, and simplifying the buffer circuit design.

[0061] In the several embodiments provided in this application, it should be understood that the disclosed circuits and methods can also be implemented in other ways. The embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the present embodiment. Those of ordinary skill in the art can understand and implement the present embodiment without inventive effort.

[0062] Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented using software plus a necessary general-purpose hardware platform, or of course, hardware. Based on this understanding, the essence of the above technical solution, or the portion that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, or an optical disk, and includes a number of instructions for causing a computer device (such as a personal computer, server, or network device) to execute the methods described in each embodiment or certain portions of the embodiments.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. An amplifier, characterized in that: The amplifier includes a fully differential amplifying module and a driving module, wherein the input end of the fully differential amplifying module receives an input differential signal, and the output end of the fully differential amplifying module is connected to the input end of the driving module; The fully differential amplification module is configured to generate a differential output signal according to the input differential signal; The driving module is used to output differential driving signals with different driving magnitudes according to the differential output signal.

2. The amplifier according to claim 1, wherein The driving module includes a first driving output circuit and a second driving output circuit, wherein the control end of the first driving output circuit is connected to a differential output end of the fully differential amplifying module, and the control end of the second driving output circuit is connected to the other differential output end of the fully differential amplifying module; The i-th driving output circuit is used to output an i-th driving signal with different driving magnitudes according to the received differential output signal; wherein, i is one or two, and the first driving signal and the second driving signal are differential signals.

3. The amplifier according to claim 2, characterized in that The first drive output circuit includes N positive-phase drive units, and the second drive output circuit includes M negative-phase drive units; The control end of the positive phase driving unit is connected to the one differential output end of the fully differential amplifying module, and the control end of the negative phase driving unit is connected to the other differential output end of the fully differential amplifying module; The i-th driving output circuit is specifically used to control at least one of the positive phase driving units or at least one of the negative phase driving units to be turned on to output the i-th driving signal with different driving magnitudes; wherein N and M are both natural numbers not less than 1.

4. The amplifier according to claim 3, characterized in that The positive phase driving unit and the negative phase driving unit corresponding to the positive phase driving unit both include a control unit and a switch pair tube, and the control end of the switch pair tube is connected to the output end of the control unit; The control unit is used to generate a control signal; The switch pair is configured to be turned on or off under the action of the control signal and output the first drive signal and / or the second drive signal.

5. The amplifier according to claim 4, characterized in that The control unit includes a plurality of switches, and the control unit is specifically configured to generate corresponding control signals according to the conduction states of the switches to control the conduction or disconnection of the switches to the tubes.

6. The amplifier according to claim 5, characterized in that The control unit includes a first switch and a second switch, and the closing states of the first switch and the second switch are opposite to each other to generate the control signal.

7. The amplifier according to claim 6, characterized in that The control unit includes a first sub-control unit and a second sub-control unit, each of the first sub-control unit and the second sub-control unit includes the first switch and the second switch, and the switch pair includes a PMOS transistor and an NMOS transistor; The source terminal of the PMOS transistor and one end of the first switch in the first sub-control unit are both connected to a first voltage, and the gate terminal of the PMOS transistor is connected to the other end of the first switch in the first sub-control unit and one end of the second switch in the first sub-control unit; The source terminal of the NMOS transistor and one end of the first switch in the second sub-control unit are both connected to the second voltage, and the gate terminal of the NMOS transistor is connected to the other end of the first switch in the second sub-control unit and one end of the second switch in the second sub-control unit; The other end of the second switch in the first sub-control unit and the second sub-control unit is connected to the differential output end of the fully differential amplifier module, the drain end of the PMOS tube is connected to the drain end of the NMOS tube, and the first voltage is higher than the second voltage.

8. The amplifier according to claim 7, characterized in that The other ends of the second switches in the first sub-control unit and the second sub-control unit in the positive phase driving unit are connected to the differential output end of the fully differential amplifying module; The other ends of the second switches in the first sub-control unit and the second sub-control unit in the inverting driving unit are connected to the other differential output end of the fully differential amplifying module.

9. A fully differential buffer, characterized in that: comprising a gain module and the amplifier according to any one of claims 1 to 8, wherein the input end of the gain module is connected to the output end of the amplifier, and the output end of the gain module is connected to the input end of the amplifier; The gain module is used to adjust the gain of the buffer and perform gain adjustment on the differential driving signal output by the amplifier according to the gain.

10. The fully differential buffer according to claim 9, wherein: The gain module includes a gain adjustment path, and the output end of the amplifier is connected to the input end of the amplifier through the gain adjustment path; The gain module is specifically configured to switch on the gain adjustment path to adjust the gain of the buffer.

11. The fully differential buffer according to claim 10, wherein: The gain adjustment path includes an adjustment load and a gain adjustment switch; The gain adjustment switch is used to control the size of the adjustment load included in the gain adjustment path to adjust the gain of the buffer.

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