Signal mismatch compensation method and circuit for quick response

Abstract

The invention discloses a signal mismatch compensation method and a signal mismatch compensation circuit for quick response, which are suitable for a mismatch elimination circuit. The mismatch elimination circuit comprises a signal path used for signal transmission and a feedback circuit used for mismatch elimination. The feedback output end of the feedback circuit is connected with the signal input end of the signal path; the signal mismatch compensation method comprises the following steps: when it is monitored that an input signal exists at a signal input end, switching on a first path to drive a feedback circuit to carry out mismatch compensation on the input signal; when it is monitored that the input signal changes, the first path is disconnected, and an output signal of the signal output end of the signal path is obtained; and the feedback circuit is driven based on the amplitude signal of the output signal to perform mismatch compensation on the input signal so as to eliminate the establishment time of the mismatch elimination circuit.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic circuits, and specifically, to a signal mismatch compensation method and circuit for fast response. Background Art

[0002] In circuit design, due to process manufacturing deviations, uncontrollable and different mismatches usually occur between different devices. The mismatch between devices will affect the performance of the circuit. Specifically, the input signal in the circuit is superimposed with the mismatch of the device, which will cause a fixed deviation in the output signal, thereby affecting the result of the output signal and generating error codes.

[0003] In the prior art, to solve the mismatch, the output mismatch is solved by an analog circuit method. Specifically, the output mismatch is eliminated by an analog feedback method. In the prior art, an analog circuit uses a negative feedback amplifier to form a negative feedback circuit. Thus, even if there is a mismatch between different devices on the signal transmission path, the mismatch can be compensated by the negative feedback amplifier, so that the mismatch on the signal transmission path does not affect the output. However, the method of using an analog circuit for mismatch compensation is not applicable to the signal burst mode because the establishment of the negative feedback loop for mismatch compensation in the analog circuit is usually relatively slow. During the intermittent transmission of signals, it is required to be able to respond quickly after receiving data. At this time, the analog loop cannot be established, thus affecting the output result. Summary of the Invention

[0004] To solve the above technical problems, the present invention discloses a signal mismatch compensation method and circuit for fast response to eliminate the establishment time of the mismatch elimination circuit and improve the effect of mismatch elimination.

[0005] To achieve the above object, the present invention discloses a signal mismatch compensation method for fast response, which is applicable to a mismatch elimination circuit; the mismatch elimination circuit includes a signal path and a feedback circuit; the feedback output end of the feedback circuit is connected to the signal input end of the signal path; wherein, the signal mismatch compensation method includes:

[0006] When it is detected that there is an input signal at the signal input end, turn on the first path to drive the feedback circuit to perform mismatch compensation on the input signal;

[0007] When it is detected that the input signal changes, disconnect the first path and obtain the output signal at the signal output end of the signal path;

[0008] Drive the feedback circuit based on the amplitude signal of the output signal to perform mismatch compensation on the input signal.

[0009] The signal mismatch compensation method for fast response disclosed by the present invention is applicable to a mismatch elimination circuit to eliminate the setup time of the mismatch elimination circuit, thereby improving the effect of signal mismatch compensation. Specifically, during the process of signal mismatch compensation, first, it is monitored in real time whether there is an input signal at the signal input end of the signal path used for signal transmission in the mismatch elimination circuit, so as to establish the connection between the feedback circuit and the signal path in a timely manner, and then the transmission of the signal is used to drive the feedback circuit to automatically compensate for the input signal for mismatch, ensuring the effect of mismatch compensation. Further, after starting the feedback circuit to eliminate the mismatch, it is monitored in real time whether the input signal changes, so that when the input signal changes, the feedback circuit is adjusted in a timely manner according to the amplitude signal of the output signal, ensuring that the working state of the feedback circuit is not affected by the change of the input signal and maintaining a consistent working state, thereby eliminating the setup time of the mismatch elimination circuit and improving the effect of mismatch elimination.

[0010] As a preferred example, the step of turning on the first path to drive the feedback circuit to perform mismatch compensation on the input signal includes:

[0011] When the input signal is detected, control the feedback input end of the feedback circuit to be connected to the signal output end of the signal path to turn on the first path;

[0012] Extract a signal from the input signal to the feedback circuit based on the first path to generate a feedback signal through the feedback circuit;

[0013] Perform mismatch compensation on the input signal based on the feedback signal.

[0014] In the above solution, the input end of the feedback circuit is connected to the signal output end of the signal path and the output end of the feedback circuit is connected to the signal input end of the signal path, thereby constructing a feedback loop to track the mismatch change of the signal in the signal path in real time, perform mismatch tracking compensation, and improve the effect of mismatch compensation.

[0015] As a preferred example, when it is detected that the input signal changes, it includes:

[0016] Obtain the state value and differential signal of the input signal at different times in real time;

[0017] Determine the signal input mode of the input signal according to the state value;

[0018] When the signal input mode changes, it is determined that the input signal has changed.

[0019] In the above solution, considering that the establishment of the analog loop is vulnerable to signal pattern changes, in order to ensure that the mismatch cancellation circuit is always in a working state to cope with input signals of different patterns without wasting time by establishing it separately, therefore, the state value of the input signal is detected in real time to determine the corresponding signal input pattern, and when the signal changes, the driving mode of the feedback circuit is adjusted in a timely manner, thereby eliminating the establishment time of the feedback circuit.

[0020] As a preferred example, driving the feedback circuit based on the amplitude signal of the output signal to perform mismatch compensation on the input signal includes:

[0021] Detect the amplitude of the output signal and output the amplitude signal corresponding to the amplitude;

[0022] Subtract the output signal and the amplitude signal to obtain the driving signal of the feedback circuit;

[0023] Send the driving signal to the feedback circuit to drive the feedback circuit to perform mismatch compensation on the input signal.

[0024] In the above solution, in order to avoid the feedback circuit being affected by the change of the input signal, the driving signal of the feedback circuit is formulated by using the output signal and the amplitude signal of the output signal, ensuring that the driving signal of the feedback circuit is continuous, thereby maintaining the working state of the feedback circuit, further eliminating the establishment time of the feedback circuit, and improving the effect of adaptive compensation.

[0025] On the other hand, the present invention discloses a signal mismatch compensation circuit for fast response, which is applicable to a mismatch cancellation circuit; the mismatch cancellation circuit includes a signal path for signal transmission and a feedback circuit for mismatch cancellation; the feedback output end of the feedback circuit is connected to the signal input end of the signal path; wherein, the signal mismatch compensation circuit includes a controller, a first switch and an amplitude detection circuit;

[0026] The switch input end of the first switch is connected to the signal output end of the signal path; the switch output end of the first switch is connected to the feedback input end of the feedback circuit; the driving end of the first switch is connected to the control end of the controller;

[0027] The input end of the amplitude detection circuit is connected to the signal output end of the signal path; the output end of the amplitude detection circuit is connected to the feedback input end of the feedback circuit;

[0028] The input end of the controller is signal-connected to the signal input end of the signal path, and is used for monitoring whether there is an input signal at the signal input end of the signal path and monitoring whether the input signal changes, so as to perform the following steps according to the monitoring results:

[0029] When an input signal is detected at the signal input end, drive the first switch to close to connect the first path connecting the signal path and the feedback circuit;

[0030] When it is detected that the input signal changes, disconnect the first path and control the amplitude detection circuit to obtain the output signal of the signal output end of the signal path;

[0031] Drive the feedback circuit based on the amplitude signal of the output signal to perform mismatch compensation on the input signal.

[0032] The signal mismatch compensation circuit for fast response disclosed by the present invention is applicable to a mismatch cancellation circuit to eliminate the setup time of the mismatch cancellation circuit, thereby improving the effect of signal mismatch compensation. Specifically, during the process of signal mismatch compensation, first, it is monitored in real time whether there is an input signal at the signal input end of the signal path used for signal transmission in the mismatch cancellation circuit, so as to establish the connection between the feedback circuit and the signal path in a timely manner, and then the feedback circuit is driven by the transmission of the signal to perform automatic mismatch compensation on the input signal, ensuring the effect of mismatch compensation. Further, after starting the feedback circuit to perform mismatch cancellation, it is monitored in real time whether the input signal changes, so that when the input signal changes, the feedback circuit is adjusted to be driven according to the amplitude signal of the output signal in a timely manner, ensuring that the working state of the feedback circuit is not affected by the change of the input signal and maintaining a consistent working state, thereby eliminating the setup time of the mismatch cancellation circuit and improving the effect of mismatch cancellation.

[0033] As a preferred example, it further includes a low-pass filter; wherein, the input end of the low-pass filter is connected to the switch output end of the first switch; the output end of the low-pass filter is connected to the feedback input end of the feedback circuit.

[0034] In the above solution, a low-pass filter is arranged between the input end of the feedback circuit and the first switch to perform signal screening, and at the same time, the low-pass filter is used to ensure that the inputs of the feedback circuit are the same, thereby maintaining the working state of the feedback circuit.

[0035] As a preferred example, it further includes a second switch; wherein, the switch input end of the second switch is connected to the output end of the amplitude detection circuit; the switch output end of the second switch is connected to the input end of the low-pass filter; the drive end of the second switch is connected to the control end of the controller;

[0036] When the controller detects that the input signal changes, drive the first switch to disconnect and drive the second switch to close.

[0037] In the above solution, the second switch is set to, when the signal changes, control the closing of the second switch, and then use the amplitude detection circuit connected thereto to adjust the drive signal of the feedback circuit, so as to ensure that the feedback circuit remains in the working state, and then eliminate the establishment time of the feedback circuit.

[0038] As a preferred example, it further includes a first adder; wherein, the input end of the first adder is connected to the signal output end of the signal path; the input end of the first adder is connected to the output end of the amplitude detection circuit; the output end of the second adder is connected to the input end of the second switch;

[0039] The first adder is used to obtain the amplitude signal output by the amplitude detection circuit and the output signal of the signal output end of the signal path, and perform subtraction processing on the output signal and the amplitude signal to output a drive signal to the low-pass filter.

[0040] In the above solution, the adder is set to ensure that the difference of the input signal of the low-pass filter is zero according to the output signal and the amplitude of the output signal, and then control the working state of the feedback circuit not to change, so as to eliminate the establishment time of the feedback circuit.

[0041] As a preferred example, it further includes a second adder; wherein, the input end of the second adder is connected to the feedback output end of the feedback circuit; the input end of the second adder is connected to the signal input end of the signal path; the output end of the second adder is connected to the signal output end of the signal path;

[0042] The second adder is used to obtain the feedback signal output by the feedback circuit and the input signal of the signal input end of the signal path, and perform addition processing on the input signal and the feedback signal to output an output signal after mismatch compensation to the signal output end of the signal path.

[0043] In the above solution, an adder is provided between the output end of the feedback circuit and the signal input end of the signal path to perform mismatch compensation on the input signal according to the feedback signal output by the feedback circuit.

[0044] As a preferred example, when it is monitored that the input signal changes, it includes;

[0045] The controller obtains the state values of the input signal at different times in real time;

[0046] The controller determines the signal input mode of the input signal according to the state values;

[0047] The controller determines that the input signal has changed when the signal input mode changes.

[0048] In the above solution, the controller detects the state value of the input signal in real time. When the input mode of the signal changes, the driving mode of the feedback circuit is adjusted in a timely manner, thereby eliminating the setup time of the feedback circuit. Description of the Drawings

[0049] Figure 1 : A schematic flowchart of a signal mismatch compensation method for fast response provided by an embodiment of the present invention;

[0050] Figure 2 : A schematic structural diagram of a signal mismatch compensation circuit for fast response provided by an embodiment of the present invention;

[0051] Figure 3 : A schematic structural diagram of a mismatch elimination circuit provided by another embodiment of the present invention;

[0052] Figure 4 : A schematic structural diagram of a signal mismatch compensation circuit for fast response provided by another embodiment of the present invention. Detailed Embodiments

[0053] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0054] Embodiment 1

[0055] In the process of the prior art compensating for mismatches by constructing a feedback loop, when the signal does not exist for a long time or the signal belongs to a burst mode and the signal is sent intermittently, since the feedback loop is only established when the signal exists and the establishment time is relatively long, it is impossible to respond to the input signal in a timely manner for mismatch compensation. In response to this, the embodiments of the present disclosure disclose a signal mismatch compensation method for controlling the fast response of the feedback loop, which is applicable to a mismatch elimination circuit including a signal path for signal transmission and a feedback circuit for mismatch elimination; wherein, the feedback output end of the feedback circuit is connected to the signal input end of the signal path.

[0056] Specifically, for the implementation process of the signal mismatch compensation method, please refer to Figure 1 , which mainly includes steps 101 to 103, and the steps are as follows:

[0057] Step 101: When an input signal is detected at the signal input end, turn on the first path to drive the feedback circuit to perform mismatch compensation on the input signal;

[0058] Step 102: When it is detected that the input signal changes, disconnect the first path and obtain the output signal of the signal output end of the signal path;

[0059] Step 103: Drive the feedback circuit based on the amplitude signal of the output signal to perform mismatch compensation on the input signal.

[0060] In a certain implementation manner of this embodiment, during the process of establishing the first channel to drive the feedback circuit to obtain partial or all of the input signal and feed it back to the input signal, so as to perform mismatch compensation on the input signal, in order to respond to the signal transmission situation in the signal path connected to the feedback circuit in a timely and rapid manner, step 101 can detect the presence of the signal in the signal input end of the signal path in real time, and timely establish a channel that can form a feedback loop between the feedback circuit and the signal path, and then drive the feedback circuit through the channel to perform mismatch compensation.

[0061] Specifically, step 101 can construct the path through the following steps, including:

[0062] Step 1011: When the input signal is detected, control the feedback input end of the feedback circuit to connect to the signal output end of the signal path to turn on the first path;

[0063] Step 1012: Extract a signal from the input signal to the feedback circuit based on the first path to generate a feedback signal through the feedback circuit;

[0064] Step 1013: Perform mismatch compensation on the input signal based on the feedback signal.

[0065] The steps adopted in the above disclosed embodiments utilize the connection between the input end of the feedback circuit and the signal output end of the signal path and the connection between the output end of the feedback circuit and the signal input end of the signal path, and then construct a feedback loop to follow the mismatch change of the signal in the signal path in real time, perform mismatch tracking compensation, and improve the effect of mismatch compensation.

[0066] In a certain implementation manner of this embodiment, considering that the feedback circuit is only in a working state when there is a signal, and the reconstruction of the feedback circuit takes a lot of time. Therefore, after the path is constructed and the feedback circuit automatically performs mismatch compensation on the input signal, it is also necessary to timely obtain the change of the signal to avoid the feedback circuit from stopping working and thus being unable to respond quickly to the signal transmission.

[0067] Specifically, step 102 can detect the change of the input signal at the signal input end in real time through the following steps, including:

[0068] Step 1021: Obtain the state values of the input signal at different times in real time;

[0069] Step 1022: Determine the signal input mode of the input signal according to the state values;

[0070] Step 1023: When the signal input mode changes, determine that the input signal has changed

[0071] In the steps adopted in the above disclosed embodiments, considering that the establishment of the analog loop is easily affected by signal mode transformation, in order to ensure that the mismatch cancellation circuit is always in a working state to cope with input signals of different input modes without wasting time in re-establishing, therefore, the state values and differential signals of the input signal are detected in real time. When the signal changes, the driving mode of the feedback circuit is adjusted in time, thereby eliminating the establishment time of the feedback circuit.

[0072] In a certain implementation manner of this embodiment, when it is recognized that the signal has changed, that is, it is recognized that the feedback circuit may stop working. At this time, in order to maintain the working state of the feedback circuit, step 103 can maintain the working state of the feedback circuit through the following steps, including:

[0073] Step 1031: Detect the amplitude of the output signal and output an amplitude signal corresponding to the amplitude;

[0074] Step 1032: Subtract the output signal and the amplitude signal to obtain the driving signal of the feedback circuit;

[0075] Step 1033: Send the driving signal to the feedback circuit to drive the feedback circuit to perform mismatch compensation on the input signal.

[0076] In the steps adopted in the above disclosed embodiments, in order to avoid the influence of the input signal transformation on the feedback circuit, the driving signal of the feedback circuit is formulated by using the output signal and the amplitude signal of the output signal, ensuring that the driving signal of the feedback circuit is continuous, thereby maintaining the working state of the feedback circuit, further eliminating the establishment time of the feedback circuit, and improving the effect of adaptive compensation.

[0077] On the other hand, this embodiment also discloses a signal mismatch compensation circuit for fast response, which is similarly applicable to a mismatch cancellation circuit including a signal path for signal transmission and a feedback circuit for mismatch cancellation; the feedback output end of the feedback circuit is connected to the signal input end of the signal path.

[0078] Specifically, for the specific structural composition of the signal mismatch compensation circuit disclosed in this embodiment, please refer to Figure 2, mainly including a controller 201, a first switch 202 and an amplitude detection circuit 203;

[0079] The switch input end of the first switch 202 is connected to the signal output end of the signal path; the switch output end of the first switch 202 is connected to the feedback input end of the feedback circuit; the drive end of the first switch 202 is connected to the control end of the controller 201;

[0080] The input end of the amplitude detection circuit 203 is connected to the signal output end of the signal path; the output end of the amplitude detection circuit 203 is connected to the feedback input end of the feedback circuit;

[0081] The input end of the controller 201 is signal-connected to the signal input end of the signal path, and is used to monitor whether there is an input signal at the signal input end of the signal path and whether the input signal changes, so as to perform the following steps according to the monitored results:

[0082] When it is monitored that there is an input signal at the signal input end, drive the first switch 202 to close to connect the first path connecting the signal path and the feedback circuit;

[0083] When it is monitored that the input signal changes, disconnect the first path and control the amplitude detection circuit 203 to obtain the output signal of the signal output end of the signal path;

[0084] Drive the feedback circuit based on the amplitude signal of the output signal to perform mismatch compensation on the input signal.

[0085] In a certain implementation manner of this embodiment, when driving the closing or opening of the first switch 202 to drive the feedback circuit to perform mismatch compensation on the input signal input to the signal path, in order to ensure the normal operation of the feedback circuit and drive the feedback circuit to maintain a normal working state, a low-pass filter can also be configured in the signal mismatch compensation circuit.

[0086] Specifically, the input end of the low-pass filter is connected to the switch output end of the first switch 202; the output end of the low-pass filter is connected to the feedback input end of the feedback circuit, so as to realize the normal operation of the feedback circuit through the low-pass filter.

[0087] In a certain implementation manner of this embodiment, when the controller 201 monitors that the signal changes, if the feedback circuit is driven according to the first switch 202 at this time, it will cause the repeated establishment of the feedback circuit, and thus it is impossible to respond to the input signal in time. To this end, in order to eliminate the establishment time wasted when the feedback circuit is re-established, a second switch can also be configured in the signal mismatch compensation circuit to change the driving mode of the feedback circuit.

[0088] Specifically, the switch input terminal of the second switch is connected to the output terminal of the amplitude detection circuit 203; the switch output terminal of the second switch is connected to the input terminal of the low-pass filter; the drive terminal of the second switch is connected to the control terminal of the controller 201, so that when the controller 201 monitors that the input signal changes, the first switch 202 is driven to disconnect and the second switch is driven to close, thereby ensuring that the feedback circuit remains in the working state to eliminate the setup time of the feedback circuit.

[0089] In a certain implementation manner of this embodiment, when starting the second switch and the amplitude detection circuit to maintain the working state of the feedback circuit, only when the drive signal of the feedback circuit remains unchanged, that is, the differential input is zero, will the feedback circuit remain in the working state all the time.

[0090] Specifically, to ensure that the drive signal of the feedback circuit remains unchanged, a first adder is provided in the signal mismatch compensation circuit. Specifically, the input terminal of the first adder is connected to the signal output terminal of the signal path; the input terminal of the first adder is connected to the output terminal of the amplitude detection circuit; the output terminal of the second adder is connected to the input terminal of the second switch; the first adder is used to obtain the amplitude signal output by the amplitude detection circuit and the output signal of the signal output terminal of the signal path, and subtract the output signal and the amplitude signal to output a drive signal to the low-pass filter.

[0091] In the above circuit structure, the adder is provided to ensure that the differential of the input signal of the low-pass filter is zero according to the output signal and the amplitude of the output signal, thereby controlling the working state of the feedback circuit not to change and eliminating the setup time of the feedback circuit.

[0092] In a certain implementation manner of this embodiment, a second adder may also be provided in the signal mismatch compensation circuit to perform mismatch compensation on the input signal according to the feedback signal output by the feedback circuit. Specifically, the input terminal of the second adder is connected to the feedback output terminal of the feedback circuit; the input terminal of the second adder is connected to the signal input terminal of the signal path; the output terminal of the second adder is connected to the signal output terminal of the signal path; the second adder is used to obtain the feedback signal output by the feedback circuit and the input signal of the signal input terminal of the signal path, and add the input signal and the feedback signal to output an output signal after mismatch compensation to the signal output terminal of the signal path.

[0093] In a certain implementation manner of this embodiment, in order to timely respond to the change of the signal and adjust the driving manner of the feedback circuit, the controller 201 acquires the state values of the input signal at different moments in real time; the controller 201 determines the signal input mode of the input signal according to the state values; when the signal input mode changes, the controller 201 determines that the input signal has changed.

[0094] In the above solution, the controller 201 detects the state value of the input signal in real time to timely adjust the driving manner of the feedback circuit when the signal changes, thereby eliminating the setup time of the feedback circuit.

[0095] The signal mismatch compensation method and circuit for fast response provided by this embodiment, during the process of signal mismatch compensation, first monitors in real time whether there is an input signal at the signal input end of the signal path for signal transmission in the mismatch elimination circuit, so as to timely establish the connection between the feedback circuit and the signal path, and then uses the transmission of the signal to drive the feedback circuit to automatically perform mismatch compensation on the input signal, ensuring the effect of mismatch compensation. Further, after starting the feedback circuit to eliminate the mismatch, it monitors in real time whether the input signal has changed, so that when the input signal changes, it timely adjusts the driving of the feedback circuit according to the amplitude signal of the output signal, ensuring that the working state of the feedback circuit is not affected by the change of the input signal and maintaining a consistent working state, thereby eliminating the setup time of the mismatch elimination circuit and improving the effect of mismatch elimination.

[0096] Embodiment Two

[0097] During the process of signal transmission, due to process manufacturing deviations, the signal is inevitably subject to uncontrollable deviations due to the mismatch between components during transmission. To address this, in the prior art, the mismatch error during signal transmission is eliminated by the method of analog feedback. Taking an amplifier circuit as an example, refer to Figure 3 , which is a schematic structural diagram of a mismatch elimination circuit for eliminating the mismatch generated when a signal is transmitted in an amplifier circuit in the prior art.

[0098] Refer to Figure 3 , first, two cascaded operational amplifiers OP1 and OP2 are set. Among them, the positive input terminal and the negative input terminal of the OP1 are respectively connected to the signal input terminal 301, OP2, the positive input terminal and the negative input terminal of the signal output terminal 302 for signal transmission and amplification. Among them, the signal input terminal 301 is used to receive the input signal sent from the outside, and the OP1 and OP2 are used to amplify the input signal. And the signal output terminal 302 is used to output the amplified input signal.

[0099] Furthermore, in order to compensate for the mismatch caused by the OP1 and OP2 pairs of signals, as Figure 3 shown, an OP3, i.e., a negative feedback amplifier, is provided to form a negative feedback loop. Among them, the positive input terminal and the negative input terminal of the OP3 are correspondingly connected to the positive input terminal and the negative input terminal of the OP2, and the output terminal of the OP3 is connected to the signal input terminal 301. Refer to Figure 3 , a negative feedback loop is formed by using the OP3, so as to ensure that the DC points of the signal output terminals are consistent. Thus, even if there is a mismatch between OP1 and OP2, it can be compensated by OP3, so that the mismatch between OP1 and OP2 does not affect the output.

[0100] However, as Figure 3 shown, the mismatch elimination circuit can perform normal mismatch elimination when the OP3 is in the normal working mode, that is, the input signal is in the normal working mode, that is, the signal transmission mode. At this time, a PRBS pattern, that is, a pattern that switches between 1 and -1, is transmitted. When the OP3 is in the abnormal working mode. For example, when the input signal is in the long 1 mode or the input signal is in the long -1 mode, at this time, the OP3 will be pulled into the abnormal working mode by the input 1 or -1. Thus, when the signal arrives, it takes a period of time for the negative feedback loop formed by the OP3 to return to the normal working mode, which will affect the establishment and normal operation of the signal at this time.

[0101] In view of this, in order to eliminate the time for the establishment of the negative feedback loop, and further make the working state of the mismatch elimination circuit consistent under any input conditions, and improve the effect of mismatch compensation. In a certain implementation manner of this embodiment, taking the Figure 3 shown mismatch elimination circuit as an example, a mismatch compensation circuit for fast response is provided to be connected to the mismatch elimination circuit, so as to control the mismatch elimination circuit to always maintain the working state.

[0102] Specifically, for the connection structure between the mismatch compensation circuit and the mismatch elimination circuit, please refer to Figure 4 , as Figure 4 shown, the mismatch compensation circuit includes a first adder 401, a low-pass filter 402, a first switch 403, a second switch 404, a second adder 405, a signal amplitude detection circuit 406 and a signal detection circuit 407.

[0103] Refer to Figure 4 , the first input terminal of the first adder 401 is connected to the signal input terminal 301, and the second input terminal of the first adder 401 is connected to the output terminal of the negative feedback amplifier OP3; the output terminal of the first adder 401 is connected to the input terminal of the operational amplifier OP1.

[0104] The output end of the low-pass filter 402 is connected to the input end of the negative feedback amplifier OP3, and the input end of the low-pass filter 402 is respectively connected to the output end of the first switch 403 and the output end of the second switch 404.

[0105] The input end of the first switch 403 is connected to the output end of the operational amplifier OP2; the input end of the second switch 404 is connected to the output end of the second adder 405.

[0106] The first input end of the second adder 405 is connected to the signal output end 302; the second input end of the second adder 405 is connected to the output end of the signal amplitude detection circuit 406.

[0107] The input end of the signal amplitude detection circuit 406 is connected to the signal output end 302.

[0108] The input end of the signal detection circuit 407 is connected to the signal input end 301; the first output end of the signal detection circuit 407 is connected to the driving end of the first switch 403; the second output end of the signal detection circuit 407 is connected to the driving end of the second switch 404.

[0109] Refer to Figure 4 , the mismatch cancellation feedback circuit constructed by OP3 can ensure that the P end and N end of the signal output end 302, that is, the output end, are equal under DC, that is, there is no mismatch.

[0110] Refer to Figure 4 When the provided mismatch compensation circuit compensates for the signal mismatch, it uses two-way switches, namely the first switch 403 and the second switch 404, to control the driving of the mismatch cancellation feedback circuit. Specifically, when the signal detection circuit 407 monitors that there is an input signal at the signal input end 301 and the signal input at the input end is in the normal working mode, that is, when the PRBS code pattern, that is, the code pattern that switches between 1 and -1, is sent to the input end in the signal sending mode, a driving signal is sent to the first switch 403 and the second switch 404, that is, S1 and S2 as shown in Figure 4 , to control S1 to close and S2 to open. At this time, the mismatch calibration of the output end is realized through the mismatch cancellation feedback circuit constructed by OP3. Specifically, since there is an input signal at the input, that is, the signal input end 301, at this time, the common-mode voltages of the output P end and output N end of the signal output end 302 are the same. At this time, the inputs of OP3 are the same after passing through the low-pass filter 402. Therefore, the differential input of OP3 is 0 and it remains in the working state.

[0111] Furthermore, when monitoring the input signal, an identification signal may be directly input from the outside to identify the identification signal to determine whether there is an input signal at the signal input terminal 301 .

[0112] On the other hand, when the signal detection circuit 407 detects that the signal input terminal 301, i.e., the input terminal, is in the long 1 or long -1 mode, it determines that the signal input terminal 301 is a burst mode signal; and when the signal input terminal is 0, it determines that there is no input signal at the signal input terminal 301.

[0113] At this time, the signal detection circuit 407 sends a driving signal to the first switch 403 and the second switch 404, that is, Figure 4 The switch S1 and S2 shown in the figure are used to open the switch S1 and close the switch S2. Further, based on the different input modes of the signal at the signal input terminal 301, i.e., the input terminal, different input modes are used to Figure 4 The mismatch elimination principle in the mismatch elimination circuit is explained. Specifically, when the input mode of the signal is long 1, the output AMP (output) of the amplitude detection circuit 406 is also 1 at this time, and then the output after the second adder 405 is: output-AMP (output) = 0, so the input seen by OP3 is 0; when the input mode of the signal is long -1, the output of the amplitude detection circuit 406: AMP (output) is also -1 at this time, and then the output after the second adder 405 is: output-AMP (output) = 0, so the input seen by OP3 is 0; when the input mode of the signal is 0, the output AMP (output) of the amplitude detection circuit 406 is also 0 at this time, and the output after the second adder 405 is: output-AMP (output) = 0, so the input seen by OP3 is 0. In summary, when the input seen by OP3 is 0, the state of OP3 will not change.

[0114] It should be noted that the mismatch elimination circuit using the amplifier as an example provided in this embodiment is not the only applicable circuit for the signal mismatch compensation circuit provided in this embodiment. The signal mismatch compensation circuit provided in this embodiment can be applied to mismatch elimination circuits where signal paths capable of signal transmission are located, such as SERDES circuits, CDR circuits, and photoelectric conversion circuits.

[0115] The signal mismatch compensation circuit for fast response provided in this embodiment can ensure that the low-pass filter and the feedback circuit remain consistent under any input conditions through a switching switch for different inputs, thereby eliminating the setup time of the mismatch elimination circuit. Further, by eliminating the setup time, the mismatch elimination circuit can be compatible with different input conditions and can be applied in working modes including but not limited to PON, etc., improving the wide applicability of mismatch elimination.

[0116] The specific embodiments described above further elaborate on the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the protection scope of the present invention. In particular, for those skilled in the art, any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A signal mismatch compensation method for fast response, characterized in that: Applicable to a mismatch elimination circuit; the mismatch elimination circuit comprises a signal path for signal transmission and a feedback circuit for mismatch elimination; the feedback output end of the feedback circuit is connected to the signal input end of the signal path; wherein the signal mismatch compensation method comprises: When it is detected that there is an input signal at the signal input terminal, the first path is connected to drive the feedback circuit to perform mismatch compensation on the input signal; When a change in the input signal is detected, disconnecting the first path and acquiring an output signal from a signal output end of the signal path; The feedback circuit is driven based on the amplitude signal of the output signal to perform mismatch compensation on the input signal.

2. The signal mismatch compensation method for fast response according to claim 1, characterized in that: The step of connecting the first path to drive the feedback circuit to perform mismatch compensation on the input signal includes: When the input signal is monitored, controlling the feedback input end of the feedback circuit to connect to the signal output end of the signal path to connect the first path; extracting a signal from the input signal to the feedback circuit based on the first path to generate a feedback signal through the feedback circuit; The input signal is mismatch compensated based on the feedback signal.

3. The signal mismatch compensation method for fast response according to claim 2, characterized in that: When the input signal is detected to have changed, the method includes: Acquire the state value of the input signal at different times in real time; determining a signal input mode of the input signal according to the state value; When the signal input mode changes, it is determined that the input signal changes.

4. The signal mismatch compensation method for fast response according to claim 3, characterized in that: The amplitude signal based on the output signal drives the feedback circuit to perform mismatch compensation on the input signal, comprising: Detecting the amplitude of the output signal, and outputting an amplitude signal corresponding to the amplitude; Subtracting the output signal from the amplitude signal to obtain a driving signal of the feedback circuit; The driving signal is sent to the feedback circuit to drive the feedback circuit to perform mismatch compensation on the input signal.

5. A signal mismatch compensation circuit for fast response, characterized in that: Applicable to a mismatch elimination circuit; the mismatch elimination circuit comprises a signal path and a feedback circuit; the feedback output end of the feedback circuit is connected to the signal input end of the signal path; wherein the signal mismatch compensation circuit comprises a controller, a first switch and an amplitude detection circuit; The switch input end of the first switch is connected to the signal output end of the signal path; the switch output end of the first switch is connected to the feedback input end of the feedback circuit; the driving end of the first switch is connected to the control end of the controller; The input end of the amplitude detection circuit is connected to the signal output end of the signal path; the output end of the amplitude detection circuit is connected to the feedback input end of the feedback circuit; The input end of the controller is connected to the signal input end of the signal path for monitoring whether there is an input signal at the signal input end of the signal path and whether the input signal changes, so as to perform the following steps according to the monitoring result: When it is detected that there is an input signal at the signal input terminal, the first switch is driven to close so as to connect the first path connecting the signal path and the feedback circuit; When a change in the input signal is detected, disconnecting the first path and controlling the amplitude detection circuit to obtain an output signal from a signal output end of the signal path; The feedback circuit is driven based on the amplitude signal of the output signal to perform mismatch compensation on the input signal.

6. The signal mismatch compensation circuit for fast response according to claim 5, characterized in that: It also includes a low-pass filter; wherein the input end of the low-pass filter is connected to the switch output end of the first switch; and the output end of the low-pass filter is connected to the feedback input end of the feedback circuit.

7. The signal mismatch compensation circuit for fast response according to claim 6, characterized in that: It also includes a second switch; wherein the switch input end of the second switch is connected to the output end of the amplitude detection circuit; the switch output end of the second switch is connected to the input end of the low-pass filter; and the driving end of the second switch is connected to the control end of the controller; When the controller detects that the input signal changes, the controller drives the first switch to open and drives the second switch to close.

8. The signal mismatch compensation circuit for fast response according to claim 7, characterized in that: It also includes a first adder; wherein the input end of the first adder is connected to the signal output end of the signal path; the input end of the first adder is connected to the output end of the amplitude detection circuit; the output end of the second adder is connected to the input end of the second switch; The first adder is used to obtain the amplitude signal output by the amplitude detection circuit and the output signal of the signal output end of the signal path, and perform subtraction processing on the output signal and the amplitude signal to output a driving signal to a low-pass filter.

9. The signal mismatch compensation circuit for fast response according to claim 5, characterized in that: It also includes a second adder; wherein the input end of the second adder is connected to the feedback output end of the feedback circuit; the input end of the second adder is connected to the signal input end of the signal path; the output end of the second adder is connected to the signal output end of the signal path; The second adder is used to obtain the feedback signal output by the feedback circuit and the input signal of the signal input end of the signal path, and add the input signal and the feedback signal to output the output signal after mismatch compensation to the signal output end of the signal path.

10. The signal mismatch compensation circuit for fast response according to claim 5, characterized in that: When the input signal is detected to have changed, the method includes: The controller acquires the state value of the input signal at different times in real time; The controller determines a signal input mode of the input signal according to the state value; The controller determines that the input signal changes when the signal input mode changes.

Images