Digital integration circuit and method, and LED driving circuit

Abstract

The present invention discloses a digital integration circuit and method, as well as an LED driving circuit. The digital integration circuit includes an oscillation control circuit, an addition and subtraction counting circuit, and a digital-to-analog conversion circuit. The oscillation control circuit is used to generate an oscillation frequency signal according to a differential signal, and the oscillation frequency signal is a digital signal. The first input end of the addition and subtraction counting circuit is connected to the output end of the oscillation control circuit, and the second input end of the addition and subtraction counting circuit receives an addition and subtraction control signal. The addition and subtraction control signal is generated according to the positive and negative directions of the differential signal. The addition and subtraction counting circuit performs an addition operation or a subtraction operation according to the addition and subtraction control signal. The addition and subtraction counting circuit counts according to the oscillation frequency signal and the addition and subtraction control signal and outputs an integration quantization result. The input end of the digital-to-analog conversion circuit is connected to the output end of the addition and subtraction counting circuit, and converts the integration quantization result into an analog integration quantity. The digital integration circuit and method proposed by the present invention can reduce the chip area and improve the integration quantization accuracy.

Description

Technical Field

[0001] The present invention belongs to the technical field of electronic circuits, relates to a digital circuit, and particularly relates to a digital integration circuit and method as well as an LED driving circuit. Background Art

[0002] In the prior art, an analog-to-digital conversion circuit (referred to as an ADC circuit) is used to digitally quantize an analog signal, and usually a voltage type or a current type is adopted. Taking the current type as an example, as Figure 1 shown, through a Sigma-Delta ADC circuit, the input current to be integrated is quantized into a digital signal through a comparator and a capacitor charge and discharge circuit, and then converted into an analog signal through a DAC circuit as the integration result. Figure 1 The ADC circuit shown can be used in a constant integration amount closed-loop control circuit, as Figure 2 shown; the achieved effect is that the integration amount of the output signal is equal to the reference amount.

[0003] The existing ADC circuits have the following defects:

[0004] (1) The voltage type ADC circuit requires several perfectly matched capacitors for charge transfer and calculation. To ensure the matching, a large chip area is required for implementation;

[0005] (2) The current type ADC circuit requires two current sources with equal amplitudes and opposite directions. The error that is difficult to match the current sources will directly affect the quantization accuracy;

[0006] (3) For applications with a large change range of the input analog quantity, increasing the quantization range of the ADC circuit will affect the quantization accuracy (current type), or greatly increase the chip area (voltage type); the reason is that the quantization range of the current type depends on the magnitudes of two reverse reference current sources. The larger the quantization range, the larger the amplitude of the reference current source, and the larger the ratio of the reference current source to the input current source, resulting in worse accuracy; the quantization range of the voltage type depends on the charge capacity ratio of the sampling capacitor and the reference capacitor. Under the condition of a certain voltage, the larger the capacitance ratio, the larger the quantization range, and the larger the chip area.

[0007] In view of this, there is an urgent need to design a new circuit for digitally quantizing an analog signal so as to overcome at least some of the above-mentioned defects existing in the existing circuits. Summary of the Invention

[0008] The present invention provides a digital integration circuit and method as well as an LED driving circuit, which can reduce the chip area and improve the integration quantization accuracy.

[0009] To solve the above technical problems, according to one aspect of the present invention, the following technical solution is adopted:

[0010] A digital integration circuit, the digital integration circuit comprising:

[0011] An oscillation control circuit for generating an oscillation frequency signal according to a differential signal, the oscillation frequency signal being a digital signal;

[0012] An addition and subtraction counting circuit, a first input terminal of which is connected to an output terminal of the oscillation control circuit, and a second input terminal of which receives an addition and subtraction control signal, the addition and subtraction control signal being generated according to the positive and negative directions of the differential signal, and the addition and subtraction counting circuit performing an addition operation or a subtraction operation according to the addition and subtraction control signal; the addition and subtraction counting circuit counts according to the oscillation frequency signal and the addition and subtraction control signal and outputs an integration quantization result; and

[0013] A digital-to-analog conversion circuit, an input terminal of which is connected to an output terminal of the addition and subtraction counting circuit, and which converts the integration quantization result into an analog integration quantity.

[0014] As an embodiment of the present invention, the digital integration circuit further comprises a direction comparison circuit, an output terminal of the direction comparison circuit being connected to a second input terminal of the addition and subtraction counting circuit;

[0015] The direction comparison circuit receives the differential signal at an input terminal, and the direction comparison circuit outputs a high level or a low level to the addition and subtraction counting circuit according to the positive and negative directions of the differential signal.

[0016] As an embodiment of the present invention, the oscillation control circuit is used for generating an oscillation frequency signal according to the absolute value of the differential signal; the oscillation frequency signal output by the oscillation control circuit is proportional to the amplitude of the differential signal.

[0017] As an embodiment of the present invention, the oscillation control circuit comprises:

[0018] A capacitor;

[0019] A charge and discharge circuit, coupled to the capacitor, for controlling the charging and discharging of the capacitor; and

[0020] A comparison circuit, a first input terminal of which is coupled to the capacitor, a second input terminal of which receives a first reference signal and / or a second reference signal, and an output terminal of which outputs an oscillation frequency signal.

[0021] As an embodiment of the present invention, when the capacitor charges to a first threshold voltage, the charge and discharge circuit controls the capacitor to discharge; when the capacitor discharges to a second threshold voltage, the charge and discharge circuit controls the capacitor to charge.

[0022] As an embodiment of the present invention, the oscillation control circuit further includes: a current mirror, a first switch, a second switch, and a NOT gate; the digital integration circuit further includes a current source, a voltage-current conversion circuit, and a rectification circuit;

[0023] The input end of the voltage-current conversion circuit is coupled to a second voltage, and the voltage-current conversion circuit converts the second voltage into a second current;

[0024] The output end of the current source outputs a set current; the output end of the current source and the output end of the voltage-current conversion circuit are respectively connected to the input end of the rectification circuit, and the output end of the rectification circuit is respectively coupled to the first end of the current mirror and the first end of the second switch; the second end of the second switch is respectively coupled to the first end of the first switch, the first end of the capacitor, and the first input end of the comparison circuit;

[0025] The second end of the first switch is coupled to the second end of the current mirror, and the third end of the current mirror is grounded; the second end of the capacitor is grounded;

[0026] The output end of the comparison circuit outputs a control signal for controlling the first switch; the output end of the comparison circuit is coupled to the input end of the NOT gate, and the control signal output by the comparison circuit is simultaneously used as the signal output by the oscillation control circuit to the addition and subtraction counting circuit; the output end of the NOT gate outputs a control signal for controlling the second switch.

[0027] As an embodiment of the present invention, the comparison circuit is a hysteresis comparator.

[0028] According to another aspect of the present invention, the following technical solution is adopted: an LED driving circuit, the LED driving circuit includes a driving control circuit and an LED load, the driving control circuit is used to drive the LED load, the driving control circuit includes the digital integration circuit as described above, and the driving control circuit performs loop control based on the analog integration quantity.

[0029] According to still another aspect of the present invention, the following technical solution is adopted: a digital integration method, the digital integration method includes:

[0030] Generating an oscillation frequency signal according to a differential signal, the oscillation frequency signal being a digital signal;

[0031] Receiving an addition and subtraction control signal, the addition and subtraction control signal being generated according to the positive and negative directions of the differential signal; counting according to the oscillation frequency signal and the addition and subtraction control signal and outputting an integration quantization result; and

[0032] Converting the integration quantization result into an analog integration quantity.

[0033] As an implementation manner of the present invention, a high-level or low-level addition and subtraction control signal is output according to the positive and negative directions of the differential signal.

[0034] As an implementation manner of the present invention, the digital integration method includes: controlling the capacitor to discharge when the capacitor charge reaches the first threshold voltage; and controlling the capacitor to charge when the capacitor discharge reaches the second threshold voltage.

[0035] As an implementation manner of the present invention, an oscillation frequency signal is generated according to the absolute value of the differential signal.

[0036] As an implementation manner of the present invention, the oscillation frequency signal is proportional to the amplitude of the differential signal.

[0037] As an implementation manner of the present invention, the differential signal is a differential current, and the differential current is obtained by performing a differential operation on a first current and a second current.

[0038] The beneficial effects of the present invention are as follows: The digital integration circuit, method and LED driving circuit proposed by the present invention can reduce the chip area and improve the integration quantization accuracy.

[0039] In a usage scenario of the present invention, the present invention has a lower requirement for circuit matching, and the current-controlled oscillator ICO requires a smaller capacitor, so the circuit area is smaller. At the same time, the present invention can have a larger integration quantization range. The quantization range of the current-controlled oscillator ICO depends on the frequency range that the ICO can output. Theoretically, it is not limited by other parameters. In actual design, it is only limited by the transistor speed and oxide layer leakage current, and a very wide quantization range can be achieved without increasing costs. In addition, the quantization accuracy of the current-controlled oscillator ICO is affected by the flip speed of the comparator, which can be improved or eliminated through design optimization, and thus is independent of the quantization range. Description of the Drawings

[0040] Figure 1 It is a circuit schematic diagram of an existing circuit for constant integration amount closed-loop control.

[0041] Figure 2 It is a circuit schematic diagram of an existing Sigma-Delta analog-to-digital converter.

[0042] Figure 3 It is a schematic diagram of the composition of the digital integration circuit in an embodiment of the present invention.

[0043] Figure 4 It is a circuit schematic diagram of the digital integration circuit in an embodiment of the present invention.

[0044] Figure 5 It is a circuit timing schematic diagram of the digital integration circuit in an embodiment of the present invention.

[0045] Figure 6 This is a flowchart of the digital integration method in an embodiment of the present invention. Detailed implementation manners

[0046] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0047] To further understand the present invention, the preferred implementation manners of the present invention will be described below in conjunction with embodiments. However, it should be understood that these descriptions are only for further explaining the features and advantages of the present invention, rather than limiting the claims of the present invention.

[0048] The description of this part only focuses on several typical embodiments, and the present invention is not limited to the scope described in the embodiments. The mutual replacement of the same or similar prior art means and some technical features in the embodiments is also within the scope of the description and protection of the present invention.

[0049] "Coupled" or "connected" in the specification includes both direct connection and indirect connection, such as connection through some active devices, passive devices or electrical conduction media; it also includes the connection through other active devices or passive devices known to those skilled in the art on the basis of achieving the same or similar functional purposes, such as connection through circuits or components such as switches and follower circuits.

[0050] The present invention discloses a digital integration circuit. Figure 3 This is a schematic diagram of the composition of the digital integration circuit in an embodiment of the present invention; please refer to Figure 3 , the digital integration circuit includes: an oscillation control circuit 1, an addition and subtraction counting circuit 2, and a digital-to-analog conversion circuit 3.

[0051] In an embodiment of the present invention, the oscillation control circuit 1 is configured to generate an oscillation frequency signal according to a differential signal, and the oscillation frequency signal is a digital signal with a variable frequency. The first input end of the addition and subtraction counting circuit 2 is connected to the output end of the oscillation control circuit 1, and the second input end of the addition and subtraction counting circuit 2 receives an addition and subtraction control signal. The addition and subtraction control signal is generated according to the positive and negative directions of the differential signal. The addition and subtraction counting circuit performs an addition operation or a subtraction operation according to the addition and subtraction control signal. Exemplarily, when the differential signal is in the positive direction, the addition and subtraction control signal is at a first level, and the addition and subtraction counting circuit performs an addition operation according to the addition and subtraction control signal; when the differential signal is in the negative direction, the addition and subtraction control signal is at a second level, and the addition and subtraction counting circuit performs a subtraction operation according to the addition and subtraction control signal. Among them, the positive direction in the positive and negative directions can be selected and specified according to actual needs, and the present invention does not limit this. The oscillation frequency signal obtained by the oscillation control circuit 1 is used as the input of the addition and subtraction counting circuit 2, and an addition and subtraction control signal for the addition and subtraction counting circuit is generated according to the positive and negative directions of the differential signal. The addition and subtraction counting circuit counts according to the oscillation frequency signal and the addition and subtraction control signal and outputs an integral quantization result. The input end of the digital-to-analog conversion circuit 3 is connected to the output end of the addition and subtraction counting circuit 2, and the integral quantization result is converted into an analog integral quantity.

[0052] In an embodiment, when the differential signal is in the positive direction, the addition and subtraction control signal is at a high level, and the addition and subtraction counting circuit will perform cumulative counting. Exemplarily, the addition and subtraction counting circuit accumulatively counts the high levels in the oscillation frequency signal at this time. When the differential signal is in the negative direction, the addition and subtraction control signal is at a low level, and the addition and subtraction counting circuit will perform decremental counting. Exemplarily, the addition and subtraction counting circuit decrementally counts the high levels in the oscillation frequency signal at this time.

[0053] In an embodiment of the present invention, the oscillation control circuit 1 is configured to generate an oscillation frequency signal according to the absolute value of the differential signal; the oscillation frequency signal output by the oscillation control circuit 1 is proportional to the amplitude of the differential signal.

[0054] Please continue to refer to Figure 3 , in an embodiment of the present invention, the digital integration circuit may further include a direction comparison circuit 4, a voltage-current conversion circuit 5, and a differential current rectification circuit 6. The two input ends of the differential current rectification circuit 6 may be a first current Iin1 and a second current Iin2 respectively, and the first current Iin1 and the second current Iin2 are also input to the direction comparison circuit 4 at the same time.

[0055] Figure 4 is a circuit schematic diagram of the digital integration circuit in an embodiment of the present invention; please refer to Figure 4, in an embodiment of the present invention, the output end of the direction comparison circuit 4 is connected to the second input end of the addition and subtraction counting circuit 2; the input end of the direction comparison circuit 4 receives a differential signal, and the differential signal can be a differential current. The direction comparison circuit outputs a high level or a low level to the addition and subtraction counting circuit 2 according to the positive and negative directions of the differential signal.

[0056] Please continue to refer to Figure 4 , in an embodiment, the oscillation control circuit 1 includes a capacitor Cap, a charge and discharge circuit, and a comparison circuit. In this embodiment, the oscillation control circuit is a current controlled oscillator. The charge and discharge circuit includes a current mirror 13, a first switch CK, and a second switch CKB. The charge and discharge circuit is coupled to the capacitor Cap to control the charging and discharging of the capacitor Cap by controlling the switch states of the first switch CK and the second switch CKB. The first input end of the comparison circuit is coupled to the first end of the capacitor Cap, the second input end of the comparison circuit is coupled to a first reference signal (which can be a first threshold voltage VTH) or a second reference signal (which can be a second threshold voltage VTL), and the output end of the comparison circuit outputs an oscillation frequency signal CK. Combining Figure 4 and Figure 5 it can be known that the oscillation frequency signal CK is proportional to the amplitude of the differential current, where the signal CAP is the capacitor voltage and can represent the amplitude of the differential current.

[0057] As Figure 4 shown, in an embodiment of the present invention, when the capacitor Cap is charged to the first threshold voltage VTH, the charge and discharge circuit controls the capacitor Cap to discharge, that is, a discharge loop is formed to discharge the capacitor Cap. When the capacitor Cap is discharged to the second threshold voltage VTL, the charge and discharge circuit controls the capacitor Cap to charge, that is, a charging loop is formed to charge the capacitor Cap.

[0058] In an embodiment of the present invention, the oscillation control circuit further includes: a current mirror 13, a first switch CK, a second switch CKB, and a NOT gate 14; the digital integration circuit can further include a current source, a voltage-current conversion circuit 5, and a differential current rectification circuit 6. The differential current rectification circuit 6 is used to rectify the first current output by the current source input to the differential current rectification circuit 6 and the second current output by the voltage-current conversion circuit and then output a current Irec to the charge and discharge circuit.

[0059] The input terminal of the voltage-current conversion circuit 5 is coupled to a second voltage, and the voltage-current conversion circuit converts the second voltage into a second current. The output terminal of the current source outputs a first current; the output terminal of the current source and the output terminal of the voltage-current conversion circuit 5 are respectively connected to the input terminals of the differential current rectification circuit 6, and the output terminal of the differential current rectification circuit 6 is respectively coupled to the first terminal of the current mirror 13 and the first terminal of the second switch CKB; the second terminal of the second switch CKB is respectively coupled to the first terminal of the first switch CK, the first terminal of the capacitor Cap, and the first input terminal of the comparison circuit. The second terminal of the first switch CK is coupled to the second terminal of the current mirror 13, and the third terminal of the current mirror 13 is grounded; the second terminal of the capacitor Cap is grounded. The output terminal of the comparison circuit outputs a control signal for controlling the first switch CK; the output terminal of the comparison circuit is coupled to the input terminal of the NOT gate 14, and the control signal output by the comparison circuit is simultaneously used as the signal output by the oscillation control circuit 1 to the addition and subtraction counting circuit 2; the output terminal of the NOT gate 14 outputs a control signal for controlling the second switch CKB.

[0060] Figure 5 is a circuit timing diagram of the digital integration circuit in an embodiment of the present invention; please refer to Figure 5 , in an embodiment of the present invention, the capacitor Cap is charged and discharged with the absolute value of the difference between the first current IIN1 and the second current IVIN2; the first current IIN1 is provided by the current source, and IVIN2 is obtained by converting the second voltage signal through the voltage-current conversion circuit; the input terminal of the differential current rectification circuit is Iin. Each time the capacitor voltage of the capacitor Cap reaches VTH or discharges to VTL during charging, the CK signal (i.e., the oscillation frequency signal) flips once, and the charging and discharging directions are switched, and at the same time, CK is used for counting by the addition and subtraction counter. Figure 4 The left part of the circuit of the capacitor Vcap in [] is essentially a charging and discharging circuit. The second switch CKB is turned on and the first switch CK is turned off to realize capacitor charging; the first switch CK is turned on and the second switch CKB is turned off to realize capacitor discharging. The comparison circuit controls the CK signal to flip according to the voltages VTH, VTL, and Vcap. Preferably, the comparison circuit is a hysteresis comparator. The magnitude relationship between the first current IIN1 and IVIN2 determines the addition and subtraction control signal of the addition and subtraction counter (i.e., Figure 5 the UP signal in []). When IIN1 > IVIN2, the UP signal is at a high level. The addition and subtraction counting circuit outputs an integrated quantization result after counting and generates an output control voltage VOUT through the digital-to-analog conversion circuit (the output control voltage VOUT is an analog signal), so as to control the increase of the output control voltage VOUT. That is, the analog integration amount can be the output control voltage VOUT. Among them, the output control voltage VOUT can be used to control the output voltage of the system where the digital integration circuit is located.

[0061] Please continue to refer toFigure 5 When IIN1 > IVIN2, the UP signal is at a high level, that is, the addition and subtraction counter performs cumulative counting. Each time the capacitor voltage of the capacitor Cap reaches VTH during charging or reaches VTL during discharging, the CK signal flips once. By the flipping of charging and discharging, a capacitor with a smaller capacitance value can be selected. When the UP signal is at a high level, the high level or low level of the CK signal can be cumulatively counted, corresponding to controlling the increase of the output control voltage VOUT. When IIN1 < IVIN2, the UP signal is at a low level, that is, the addition and subtraction counter performs subtractive counting. Each time the capacitor voltage of the capacitor Cap reaches VTH during charging or reaches VTL during discharging, the CK signal flips once. When the UP signal is at a low level, the high level or low level of the CK signal can be subtractively counted, corresponding to controlling the decrease of the output control voltage VOUT.

[0062] An embodiment of the present invention also discloses an LED driving circuit. The LED driving circuit includes a driving control circuit and an LED load, and the driving control circuit is used to drive the LED load. The driving control circuit includes the digital integration circuit as described in any of the above embodiments, and the driving control circuit performs loop control based on the analog integration quantity. Specifically, the digital integration circuit acquires a sampling signal representing the current flowing through the LED load, obtains an analog integration quantity after the digital integration processing of the present invention, and the driving control circuit controls the main switching tube in the LED driving circuit based on the analog integration quantity, thereby realizing the loop control of the LED driving circuit, and can be used to realize the constant current output or constant power output of the LED driving circuit.

[0063] The present invention also discloses a digital integration method. Figure 6 is a flowchart of the digital integration method in an embodiment of the present invention; please refer to Figure 6 In an embodiment of the present invention, the digital integration method includes:

[0064] Step S1: Generate an oscillation frequency signal according to the differential signal, and the oscillation frequency signal is a digital signal;

[0065] Step S2: Receive an addition and subtraction control signal, and the addition and subtraction control signal is generated according to the positive and negative directions of the differential signal; perform counting according to the oscillation frequency signal and the addition and subtraction control signal and output an integral quantization result; and

[0066] Step S3: Convert the integral quantization result into an analog integration quantity.

[0067] In an embodiment of the present invention, a high level or a low level is output to the addition and subtraction counting circuit according to the positive and negative directions of the differential signal as the addition and subtraction control signal of the addition and subtraction counting circuit.

[0068] In an embodiment of the present invention, the digital integration method includes: controlling the capacitor to discharge when the capacitor charge reaches a first threshold voltage (which can be VTH for example); and controlling the capacitor to charge when the capacitor discharge reaches a second threshold voltage (which can be VTL for example).

[0069] In an embodiment of the present invention, the step of generating an oscillation frequency signal according to a differential signal specifically includes: generating an oscillation frequency signal according to the absolute value of the differential signal.

[0070] In an embodiment of the present invention, the oscillation frequency signal is proportional to the amplitude of the differential signal.

[0071] In an embodiment of the present invention, the differential signal is a differential current, and the differential current is obtained by performing a differential operation on a first current IIN1 and a second current IVIN2.

[0072] In summary, the digital integration circuit and method and the LED driving circuit proposed by the present invention can reduce the chip area of a chip adopting the digital integration circuit and improve the integration quantization accuracy. The present invention has a lower requirement for circuit matching degree, and the current controlled oscillator ICO requires a smaller capacitor, so the circuit area is smaller. At the same time, the present invention has a larger quantization range. The quantization range of the current controlled oscillator ICO depends on the frequency range that the ICO can output. Theoretically, it is not limited by other parameters. In actual design, it is only limited by the transistor speed and the oxide layer leakage current, and a very wide quantization range can be achieved without increasing the cost. In addition, the quantization accuracy of the current controlled oscillator ICO is affected by the switching speed of the comparator, which can be improved or eliminated through design optimization and has nothing to do with the quantization range.

[0073] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0074] The description and application of the present invention here are illustrative, and it is not intended to limit the scope of the present invention to the above embodiments. The effects or advantages involved in the embodiments may not be reflected in the embodiments due to various factors. The description of the effects or advantages is not used to limit the embodiments. The deformations and changes of the embodiments disclosed here are possible, and the substitutions and equivalent components of the embodiments are well known to those of ordinary skill in the art. Those skilled in the art should clearly understand that the present invention can be implemented in other forms, structures, arrangements, proportions, and with other components, materials, and parts without departing from the spirit or essential features of the present invention. Other deformations and changes can be made to the embodiments disclosed here without departing from the scope and spirit of the present invention.

Claims

1. A digital integration circuit, characterized in that, The digital integration circuit includes: An oscillation control circuit for generating an oscillation frequency signal according to a differential signal, where the oscillation frequency signal is a digital signal; An addition and subtraction counting circuit, whose first input terminal is connected to the output terminal of the oscillation control circuit, and whose second input terminal receives an addition and subtraction control signal. The addition and subtraction control signal is generated according to the positive and negative directions of the differential signal. The addition and subtraction counting circuit performs an addition operation or a subtraction operation according to the addition and subtraction control signal; the addition and subtraction counting circuit counts according to the oscillation frequency signal and the addition and subtraction control signal and outputs an integration quantization result; and A digital-to-analog conversion circuit, whose input terminal is connected to the output terminal of the addition and subtraction counting circuit, and converts the integration quantization result into an analog integration quantity; The oscillation control circuit includes: A capacitor; A charge and discharge circuit coupled to the capacitor for controlling the charging and discharging of the capacitor; the charge and discharge circuit controls the capacitor to discharge when the capacitor charges to a first threshold voltage; the charge and discharge circuit controls the capacitor to charge when the capacitor discharges to a second threshold voltage; and A comparison circuit, whose first input terminal is coupled to the capacitor, whose second input terminal receives the first threshold voltage and / or the second threshold voltage, and whose output terminal outputs an oscillation frequency signal.

2. The digital integration circuit according to claim 1, wherein: The digital integration circuit further includes a direction comparison circuit, and the output terminal of the direction comparison circuit is connected to the second input terminal of the addition and subtraction counting circuit; The input terminal of the direction comparison circuit receives the differential signal, and the direction comparison circuit outputs a high level or a low level to the addition and subtraction counting circuit according to the positive and negative directions of the differential signal.

3. The digital integration circuit according to claim 1, wherein: The oscillation control circuit is used to generate an oscillation frequency signal according to the absolute value of the differential signal; the oscillation frequency signal output by the oscillation control circuit is proportional to the amplitude of the differential signal.

4. The digital integration circuit according to claim 1, wherein: The oscillation control circuit further includes a current mirror, a first switch, a second switch and a NOT gate; the digital integration circuit further includes a current source, a voltage-current conversion circuit and a rectification circuit; The input terminal of the voltage-current conversion circuit is coupled to a second voltage, and the voltage-current conversion circuit converts the second voltage into a second current; The output terminal of the current source outputs a set current; the output terminal of the current source and the output terminal of the voltage-current conversion circuit are respectively connected to the input terminals of the rectification circuit, and the output terminal of the rectification circuit is respectively coupled to the first terminal of the current mirror and the first terminal of the second switch; the second terminal of the second switch is respectively coupled to the first terminal of the first switch, the first terminal of the capacitor and the first input terminal of the comparison circuit; The second terminal of the first switch is coupled to the second terminal of the current mirror, the third terminal of the current mirror is grounded; the second terminal of the capacitor is grounded; The output terminal of the comparison circuit outputs a control signal for controlling the first switch; the output terminal of the comparison circuit is coupled to the input terminal of the NOT gate, and the control signal output by the comparison circuit is simultaneously used as the signal output by the oscillation control circuit to the addition and subtraction counting circuit; the output terminal of the NOT gate outputs a control signal for controlling the second switch.

5. The digital integration circuit according to claim 1, characterized in that The comparison circuit is a hysteresis comparator.

6. An LED driving circuit, the LED driving circuit comprising a driving control circuit and an LED load, the driving control circuit being used for driving the LED load, characterized in that, The drive control circuit includes the digital integration circuit according to any one of claims 1-5, and the drive control circuit performs loop control based on the analog integration amount.

7. A digital integration method for the digital integration circuit according to any one of claims 1-5, characterized in that, The digital integration method includes: Generating an oscillation frequency signal according to the differential signal, where the oscillation frequency signal is a digital signal; Receiving an addition and subtraction control signal, where the addition and subtraction control signal is generated according to the positive and negative directions of the differential signal; counting according to the oscillation frequency signal and the addition and subtraction control signal and outputting an integration quantization result; and Converting the integration quantization result into an analog integration amount.

8. The digital integration method according to claim 7, wherein: Outputting a high-level or low-level addition and subtraction control signal according to the positive and negative directions of the differential signal.

9. The digital integration method according to claim 7, wherein: The digital integration method includes: when the capacitor is charged to the first threshold voltage, controlling the capacitor to discharge; when the capacitor is discharged to the second threshold voltage, controlling the capacitor to charge.

10. The digital integration method according to claim 7, characterized in that, Generating an oscillation frequency signal according to the absolute value of the differential signal.

11. The digital integration method according to claim 10, characterized in that, The oscillation frequency signal is proportional to the amplitude of the differential signal.

12. The digital integration method according to claim 11, characterized in that, The differential signal is a differential current, and the differential current is obtained by performing a differential operation on the first current and the second current.

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