Dimming signal processing method, signal processing circuit and silicon controlled rectifier dimming chip

Abstract

The invention provides a dimming signal processing method, a signal processing circuit and a silicon controlled dimming chip. The signal processing circuit comprises: a conversion module, which is used for converting a dimming signal into a square wave signal to obtain a reference signal; the comparison module is used for comparing the reference signal with the to-be-modulated signal read from the storage module; the adjusting module is controlled by a comparison result output by the comparison module to start working and is used for reading the reference signal and the signal to be adjusted from the storage module and adjusting the signal to be adjusted according to a difference value of high level duration of the two signals; and the storage module is used for storing the preset square wave signal, providing the preset square wave signal as an initial signal to be modulated to the comparison module and the adjustment module, and storing the reference signal output by the conversion module and the signal to be modulated output by the adjustment module. According to the invention, the problems of large output current ripple, large system circuit area, high cost, poor stability, low integration level and the like when an off-chip integrating capacitor circuit is used to process the dimming signal in the prior art are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of LED dimming, and particularly to a method for processing a dimming signal, a signal processing circuit, and a thyristor dimming chip. Background Art

[0002] In traditional thyristor dimming schemes, an off-chip integrating capacitor circuit is generally used to process the dimming signal. However, the use of the off-chip integrating capacitor circuit brings many problems to the system circuit. For example, due to the low frequency of the dimming signal, the off-chip integrating capacitor circuit often causes the filtering to be unable to be flattened, resulting in a large output current ripple. Moreover, the charging and discharging of the off-chip integrating capacitor circuit requires a certain amount of time, making the response speed of the system circuit slow. In addition, the use of the off-chip integrating capacitor circuit not only increases the area and power consumption of the system circuit, but also reduces the system stability and integration.

[0003] In view of this, providing a new dimming signal processing circuit and method is an urgent technical problem to be solved by those skilled in the art. Summary of the Invention

[0004] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a method for processing a dimming signal, a signal processing circuit, and a thyristor dimming chip, which are used to solve the problems of large output current ripple, large system circuit area, high cost, poor stability, low integration, etc. when the existing off-chip integrating capacitor circuit is used to process the dimming signal.

[0005] To achieve the above purpose and other related purposes, the present invention provides a signal processing circuit, and the signal processing circuit includes:

[0006] a conversion module, a comparison module, an adjustment module, and a storage module;

[0007] The conversion module receives the dimming signal and converts the dimming signal into a square wave signal to obtain a reference signal;

[0008] The comparison module is connected to the conversion module and is used to compare the reference signal with the signal to be adjusted read from the storage module;

[0009] The adjustment module is connected to the comparison module and starts to work under the control of the comparison result output by the comparison module. It is used to read the reference signal and the signal to be adjusted from the storage module, and adjust the signal to be adjusted according to the difference in the high-level duration of the two signals;

[0010] The storage module is connected to the conversion module, the comparison module, and the adjustment module, and is configured to store a preset square wave signal and provide it as the initial signal to be adjusted to the comparison module and the adjustment module, and to store the reference signal output by the conversion module and the signal to be adjusted output by the adjustment module.

[0011] Optionally, the conversion module includes a comparator and an inverter; the positive input terminal of the comparator is connected to the dimming signal, the negative input terminal is connected to the reference signal, the output terminal is connected to the input terminal of the inverter, and the output terminal of the inverter outputs the reference signal.

[0012] Optionally, the adjustment module includes a first adjustment unit and a second adjustment unit;

[0013] The first adjustment unit starts to work when the reference signal is less than the signal to be adjusted, and is configured to read the reference signal and the signal to be adjusted from the storage module, and obtain the difference in the high-level duration of the two signals as the adjustment amount, and perform signal adjustment by performing a subtraction operation on the high-level duration of the signal to be adjusted and the adjustment amount;

[0014] The second adjustment unit starts to work when the reference signal is greater than the signal to be adjusted, and is configured to read the reference signal and the signal to be adjusted from the storage module, and obtain the difference in the high-level duration of the two signals as the adjustment amount, and perform signal adjustment by performing an addition operation on the high-level duration of the signal to be adjusted and the adjustment amount.

[0015] Optionally, the adjustment module further includes a counting unit, which is triggered by the comparison result output by the comparison module and is configured to count the number of adjustments of the signal to be adjusted.

[0016] Optionally, the signal processing circuit further includes a shaping module, which is connected between the comparison module and the storage module and is configured to perform waveform shaping on the signal to be adjusted output by the storage module.

[0017] Optionally, the signal processing circuit further includes a drive control module, which is connected to the storage module and is configured to read the signal to be adjusted from the storage module, perform an inversion process on the signal to be adjusted to obtain a control signal, and obtain a drive signal by integrating the control signal with a NEMA curve.

[0018] The present invention further provides a method for processing a dimming signal, and the processing method includes:

[0019] Step S1: Convert the dimming signal into a square wave signal to obtain a reference signal;

[0020] Step S2: Read the signal to be adjusted, compare the reference signal and the signal to be adjusted, and adjust the signal to be adjusted according to the difference in the high-level duration of the two signals.

[0021] Optionally, the method for obtaining the reference signal includes:

[0022] Convert the dimming signal into the square wave signal according to the reference signal, and perform an inversion process on the square wave signal to obtain the reference signal.

[0023] Optionally, the method for adjusting the signal to be adjusted includes:

[0024] If the reference signal is less than the signal to be adjusted, then: obtain the difference in the high-level duration of the two signals as the adjustment amount, and perform a subtraction operation on the high-level duration of the signal to be adjusted and the adjustment amount to perform signal adjustment;

[0025] If the reference signal is greater than the signal to be adjusted, then: obtain the difference in the high-level duration of the two signals as the adjustment amount, and perform an addition operation on the high-level duration of the signal to be adjusted and the adjustment amount to perform signal adjustment.

[0026] Optionally, the processing method further includes:

[0027] Step S3: Repeat Step S2 until the signal to be adjusted is consistent with the reference signal.

[0028] Optionally, the processing method further includes:

[0029] Step S4: Perform an inversion process on the signal to be adjusted to obtain the control signal, and obtain the drive signal by integrating the NEMA curve of the control signal.

[0030] The present invention also provides a thyristor dimming chip, and the thyristor dimming chip includes the signal processing circuit as described above.

[0031] As described above, for the dimming signal processing method, signal processing circuit and thyristor dimming chip of the present invention, the signal processing circuit is used to replace the off-chip integration capacitor circuit to process the dimming signal, which can completely solve the output current ripple problem; moreover, the signal processing circuit can be integrated inside the thyristor dimming chip, which reduces the area and power consumption of the system circuit, improves the stability and integration of the system circuit while ensuring the good working performance of the circuit. Description of the Drawings

[0032] Figure 1 It shows a schematic structural diagram of the signal processing circuit of the present invention.

[0033] Figure 2It shows the relevant signal waveform diagram of the signal processing circuit of the present invention.

[0034] Figure 3 It shows the flowchart of the dimming signal processing method of the present invention.

[0035] Figure 4 It shows the structural schematic diagram of the thyristor dimming chip of the present invention.

[0036] Description of component labels

[0037] 100 Signal processing circuit

[0038] 110 Conversion module

[0039] 111 Comparator

[0040] 112 Inverter

[0041] 120 Comparison module

[0042] 130 Adjustment module

[0043] 131 First adjustment unit

[0044] 132 Second adjustment unit

[0045] 133 Counting unit

[0046] 140 Storage module

[0047] 150 Shaping module

[0048] 160 Drive control module

[0049] 161 Inverting unit

[0050] 161a Counter

[0051] 161b Subtractor

[0052] 162 Digital-to-analog conversion unit

[0053] 162a Digital-to-analog converter

[0054] 162b Voltage calibrator

[0055] 163 Curve integration unit

[0056] 200 Current control circuit

[0057] 300 Signal acquisition circuit

[0058] 400 Capacitor charging circuit

[0059] 500 Charging control circuit

[0060] 600 Voltage generation circuit

[0061] 700 Access detection circuit

[0062] 800 Discharge circuit

[0063] 900 Discharge control circuit Specific implementation manners

[0064] The following uses specific examples to illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0065] Please refer to Figures 1 to 4 . It should be noted that the diagrams provided in this embodiment only illustrate the basic concept of the present invention in a schematic manner. Therefore, only the components related to the present invention are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The forms, quantities, and proportions of the components in actual implementation can be arbitrarily changed, and the layout form of the components may also be more complex.

[0066] Embodiment 1

[0067] As Figure 1 shown, this embodiment provides a signal processing circuit 100, including a conversion module 110, a comparison module 120, an adjustment module 130, and a storage module 140; further, it further includes a shaping module 150 and / or a drive control module 160.

[0068] The conversion module 110 receives the dimming signal Dim and converts the dimming signal Dim into a square wave signal Siga to obtain a reference signal SigA.

[0069] In a possible implementation manner, the conversion module 110 converts the dimming signal Dim into a square wave signal Siga according to the reference signal Ref, and performs an inversion process on the square wave signal Siga to obtain a reference signal SigA.

[0070] As an example, the conversion module 110 includes a comparator 111 and an inverter 112; the positive input terminal of the comparator 111 is connected to the dimming signal Dim, the negative input terminal is connected to the reference signal Ref, and the output terminal outputs the square wave signal Siga; the input terminal of the inverter 112 is connected to the output terminal of the comparator 111 to receive the square wave signal Siga, and the output terminal outputs the reference signal SigA; among them, the relevant signal waveforms related to the comparator 111 and the inverter 112 are as Figure 2 shown.

[0071] Of course, in other possible implementation manners, the conversion module 110 may also convert the dimming signal Dim into a square wave signal according to the reference signal Ref and directly use it as the reference signal SigA. At this time, the conversion module 110 only includes a comparator; the inverting input terminal of the comparator is connected to the dimming signal Dim, the non-inverting input terminal is connected to the reference signal Ref, and the output terminal directly outputs the reference signal SigA.

[0072] The comparison module 120 is connected to the conversion module 110 and is configured to compare the reference signal SigA and the signal to be adjusted SigB read from the storage module 140.

[0073] As an example, the comparison module 120 includes a comparator; in order to distinguish the comparators in the conversion module 110 and the comparison module 120, the comparator in the conversion module 110 is denoted as an analog comparator, and the comparator in the comparison module 120 is denoted as a digital comparator.

[0074] At this time, the first input terminal of the digital comparator is connected to the output terminal of the conversion module 110 to receive the reference signal SigA, the second input terminal is connected to the output terminal of the storage module 140 to read the signal to be adjusted SigB, and the output terminal outputs the comparison result. Among them, the first input terminal serves as the inverting input terminal, and the second input terminal serves as the non-inverting input terminal; of course, it is also feasible that the first input terminal serves as the non-inverting input terminal and the second input terminal serves as the inverting input terminal.

[0075] The adjustment module 130 is connected to the comparison module 120 and starts to work under the control of the comparison result output by the comparison module 120. It is configured to read the reference signal SigA and the signal to be adjusted SigB from the storage module 140, and adjust the signal to be adjusted SigB according to the difference in the high-level duration of the two signals.

[0076] As an example, the adjustment module 130 includes a first adjustment unit 131 and a second adjustment unit 132. Further, it also includes a counting unit 133.

[0077] The first adjustment unit 131 starts to work when the reference signal SigA is less than the signal to be adjusted SigB. At this time, the levels of the reference signal SigA and the signal to be adjusted SigB are "01"; the first adjustment unit 131 is configured to read the reference signal SigA and the signal to be adjusted SigB from the storage module 140, and obtain the difference ΔS01 in the high-level duration of the two signals as the adjustment amount, and perform signal adjustment by performing a subtraction operation on the high-level duration of the signal to be adjusted SigB and the adjustment amount.

[0078] After obtaining the difference △S01, the first adjustment unit 131 is further configured to compare the difference △S01 with 0. If the difference △S01 is equal to 0, the first adjustment unit 131 does not perform signal adjustment. If the difference △S01 is greater than 0, the first adjustment unit 131 performs signal adjustment and outputs the adjusted signal to be adjusted, SigB, to the storage module 140 for storage update. Wherein, the adjusted signal to be adjusted, SigB = the signal to be adjusted, SigB before adjustment - the adjustment amount.

[0079] In the application, the reference signal SigA and the signal to be adjusted, SigB, stored in the storage module 140 are actually the number of oscillation signals corresponding to the high and low level durations of the two signals. At this time, the first adjustment unit 131 records the number of oscillation signals corresponding to the high level duration of the signal to be adjusted, SigB, as the first count value, Cou1, and records the number of oscillation signals corresponding to the difference △S01 as the second count value, Cou2. The signal adjustment is performed by subtracting the second count value, Cou2, from the first count value, Cou1. At this time, the number of oscillation signals corresponding to the high level duration of the signal to be adjusted, SigB, is Cou1 - Cou2. Correspondingly, the number of oscillation signals corresponding to the low level duration is increased by Cou2 on the original basis, as Figure 2 shown.

[0080] The second adjustment unit 132 starts to work when the reference signal SigA is greater than the signal to be adjusted, SigB. At this time, the levels of the reference signal SigA and the signal to be adjusted, SigB, are "10". The second adjustment unit 132 is configured to read the reference signal SigA and the signal to be adjusted, SigB, from the storage module 140, and obtain the difference △S10 between the high level durations of the two signals as the adjustment amount. The signal adjustment is performed by adding the adjustment amount to the high level duration of the signal to be adjusted, SigB.

[0081] After obtaining the difference △S10, the second adjustment unit 132 is further configured to compare the difference △S10 with 0. If the difference △S10 is equal to 0, the second adjustment unit 132 does not perform signal adjustment. If the difference △S10 is greater than 0, the second adjustment unit 132 performs signal adjustment and outputs the adjusted signal to be adjusted, SigB, to the storage module 140 for storage update. Wherein, the adjusted signal to be adjusted, SigB = the signal to be adjusted, SigB before adjustment + the adjustment amount.

[0082] In the application, the reference signal SigA and the signal to be adjusted SigB stored in the storage module 140 are actually the number of oscillation signals corresponding to the high and low level durations of the two signals. At this time, the second adjustment unit 132 records the number of oscillation signals corresponding to the high level duration of the signal to be adjusted SigB as the first count value Cou1, and records the number of oscillation signals corresponding to the difference △S10 as the second count value Cou2, and performs signal adjustment by performing an addition operation on the first count value Cou1 and the second count value Cou2. At this time, the number of oscillation signals corresponding to the high level duration of the signal to be adjusted SigB is Cou1 + Cou2. Correspondingly, the number of oscillation signals corresponding to the low level duration is reduced by Cou2 on the original basis, as Figure 2 shown

[0083] The counting unit 133 is triggered by the comparison result output by the comparison module 120 and is used to count the adjustment times of the signal to be adjusted SigB. In the application, the counting unit 133 outputs the counted adjustment times of the signal to be adjusted SigB to the storage module 140 for storage.

[0084] In a possible implementation manner, the counting unit 133 is triggered by the comparison result output by the comparison module 120. For example, when the reference signal SigA is less than the signal to be adjusted SigB, and when the reference signal SigA is greater than the signal to be adjusted SigB, the counting unit 134 is triggered, and the adjustment times of the signal to be adjusted SigB are counted by successively decreasing a specific value from a preset value, where the preset value is preferably the maximum count value of the counting unit 133. Of course, in other possible implementation manners, the counting unit 133 can also count the adjustment times of the signal to be adjusted SigB by successively increasing a specific value from a preset value, where the preset value is preferably zero. In addition, the specific value is an integer greater than or equal to 1, preferably 1.

[0085] The storage module 140 is connected to the conversion module 110, the comparison module 120, and the adjustment module 130, and is used to store a preset square wave signal and provide it as an initial signal to be adjusted SigB to the comparison module 120 and the adjustment module 130, and store the reference signal SigA output by the conversion module 110 and the signal to be adjusted SigB output by the adjustment module 130.

[0086] As an example, the storage module 140 includes a digital memory. Among them, the reference signal SigA and the signal to be adjusted SigB stored in the digital memory are actually the number of oscillation signals corresponding to the high and low level durations of the two signals.

[0087] It should be noted that the signal to be adjusted SigB stored in the storage module 140 will be continuously updated according to the output of the first adjustment unit 131 or the second adjustment unit 132. Each time it is updated, the new signal to be adjusted SigB will overwrite the old signal to be adjusted SigB.

[0088] When the signal processing circuit 100 includes a shaping module 150, the shaping module 150 is connected between the comparison module 120 and the storage module 140, and is used to perform waveform shaping on the signal to be adjusted SigB output by the storage module 140 and then output it to the comparison module 120. Among them, the shaping module 150 can be implemented by an existing waveform shaping circuit, and this embodiment does not limit this.

[0089] When the signal processing circuit 100 includes a drive control module 160, the drive control module 160 is connected to the storage module 140, and is used to read the signal to be adjusted SigB from the storage module 140, perform an inversion process on the signal to be adjusted SigB to obtain a regulation signal, and integrate the NEMA curve on the regulation signal to obtain a drive signal for facilitating dimming control.

[0090] As an example, the drive control module 160 includes an inversion unit 161, a digital-to-analog conversion unit 162, and a curve integration unit 163.

[0091] The inversion unit 161 is connected to the storage module 140, and is used to perform an inversion process on the signal to be adjusted SigB to obtain a regulation signal.

[0092] Specifically, the inversion unit 161 includes a counter 161a and a subtractor 161b; the counter 161a is used to provide the maximum pre-designed value CMR, and the subtractor 161b receives the maximum pre-designed value CMR and the signal to be adjusted SigB, and performs a subtraction operation on the maximum pre-designed value CMR and the signal to be adjusted SigB to implement the inversion process on the signal to be adjusted SigB to obtain a regulation signal. Of course, it is also feasible to use other circuit structures such as an inverter that can implement the inversion function.

[0093] The digital-to-analog conversion unit 162 is connected to the inversion unit 161, and is used to perform digital-to-analog conversion on the regulation signal and then output it.

[0094] Specifically, the digital-to-analog conversion unit 162 includes a digital-to-analog converter 162a and a voltage calibrator 162b; the digital-to-analog converter 162a receives the regulation signal and performs digital-to-analog conversion on the regulation signal and then outputs it; the voltage calibrator 162 receives the reference voltage VREF and dynamically adjusts the reference voltage VREF according to the analog quantity corresponding to the maximum pre-designed value CMR to provide a voltage reference for the digital-to-analog converter 162a.

[0095] The curve integration unit 163 is connected to the digital-to-analog conversion unit 162 and is configured to perform NEMA curve integration on the regulated signal after digital-to-analog conversion to obtain a drive signal.

[0096] Among them, the curve integration unit 163 performs NEMA curve integration on the regulated signal according to the SSL 6 (Solid State Lighting Incandescent Replacement - Dimming) standard to obtain a drive signal; the SSL 6 standard is mainly for the phase - controlled dimming application of LED replacement lamps based on incandescent lamp bases, with technical requirements that the phase - control angle is 40° or less, and the dimming output should not be greater than 25% when the conduction angle is 40° or lower.

[0097] It should be noted that the signal processing circuit 100 may include only the shaping module 150, or only the drive control module 160, or may include both the shaping module 150 and the drive control module 160 at the same time. When both the shaping module 150 and the drive control module 160 are included, the signal to be adjusted SigB input to the drive control module 160 may be provided by the storage module 140, as Figure 1 shown; of course, it may also be provided by the shaping module 150. At this time, the shaping module 150 is connected between the storage module 140 and the drive control module 160.

[0098] As Figure 3 shown, this embodiment also provides a method for processing a dimming signal, including step S1 and step S2; further, it also includes step S3 and step S4. Among them, this processing method can be implemented by using the signal processing circuit 100 described above. Of course, other circuits capable of implementing this processing method are also feasible.

[0099] Step S1: Convert the dimming signal Dim into a square - wave signal Siga to obtain a reference signal SigA.

[0100] In a possible implementation manner, the method for obtaining the reference signal SigA includes: converting the dimming signal Dim into a square - wave signal Siga according to the reference signal Ref. For example, comparing the dimming signal Dim and the reference signal Ref, generating a high level when the dimming signal Dim is greater than the reference signal Ref, and outputting a low level when the dimming signal Dim is less than the reference signal Ref. In this way, the square - wave signal Siga is obtained, and the square - wave signal Siga is inverted to obtain the reference signal SigA.

[0101] In other possible implementation manners, the method for obtaining the reference signal SigA includes: converting the dimming signal Dim into a square wave signal Siga as the reference signal SigA according to the reference signal Ref. For example, by comparing the dimming signal Dim and the reference signal Ref, generating a low level when the dimming signal Dim is greater than the reference signal Ref, and outputting a high level when the dimming signal Dim is less than the reference signal Ref. In this way, the square wave signal Siga is directly obtained as the reference signal SigA without undergoing an inversion process.

[0102] Step S2: Read the signal to be adjusted SigB, compare the reference signal SigA and the signal to be adjusted SigB, and adjust the signal to be adjusted SigB according to the difference in the high-level duration of the two signals.

[0103] It should be noted that when step S2 is executed for the first time, the signal to be adjusted SigB read is a preset square wave signal. When step S2 is executed for the second time and subsequent times, the signal to be adjusted SigB read is the signal to be adjusted SigB after being adjusted in the previous execution of step S2.

[0104] In one possible implementation manner, the method for adjusting the signal to be adjusted SigB includes the following steps.

[0105] If the reference signal SigA is less than the signal to be adjusted SigB, that is, the levels of the reference signal SigA and the signal to be adjusted SigB are "01", then: obtain the difference △S01 in the high-level duration of the two signals as the adjustment amount, and perform signal adjustment by subtracting the adjustment amount from the high-level duration of the signal to be adjusted SigB.

[0106] After obtaining the difference △S01, compare the difference △S01 with 0. If the difference △S01 is equal to 0, no signal adjustment is performed. If the difference △S01 is greater than 0, signal adjustment is performed and the adjusted signal to be adjusted SigB is stored and updated. Wherein, the adjusted signal to be adjusted SigB = the signal to be adjusted SigB before adjustment - the adjustment amount.

[0107] Among them, the specific method for performing signal adjustment by subtraction operation includes: denoting the number of oscillation signals corresponding to the high-level duration of the signal to be adjusted SigB as the first count value Cou1, denoting the number of oscillation signals corresponding to the difference △S01 as the second count value Cou2, and performing signal adjustment by subtracting the second count value Cou2 from the first count value Cou1; at this time, the number of oscillation signals corresponding to the high-level duration of the signal to be adjusted SigB is Cou1 - Cou2, and correspondingly, the number of oscillation signals corresponding to the low-level duration is increased by Cou2 on the original basis.

[0108] If the reference signal SigA is greater than the signal to be adjusted SigB, that is, the levels of the reference signal SigA and the signal to be adjusted SigB present "10", then: obtain the difference △S10 between the high-level durations of the two signals as the adjustment amount, and perform signal adjustment by performing an addition operation on the high-level duration of the signal to be adjusted SigB and the adjustment amount.

[0109] After obtaining the difference △S10, it is also compared with 0. If the difference △S10 is equal to 0, no signal adjustment is performed. If the difference △S10 is greater than 0, signal adjustment is performed and the adjusted signal to be adjusted SigB is stored and updated. Among them, the adjusted signal to be adjusted SigB = the signal to be adjusted SigB before adjustment + the adjustment amount.

[0110] Among them, the specific method of signal adjustment by addition operation includes: recording the number of oscillation signals corresponding to the high-level duration of the signal to be adjusted SigB as the first count value Cou1, and recording the number of oscillation signals corresponding to the difference △S10 as the second count value Cou2, and performing signal adjustment by performing an addition operation on the first count value Cou1 and the second count value Cou2; at this time, the number of oscillation signals corresponding to the high-level duration of the signal to be adjusted SigB is Cou1 + Cou2, and correspondingly, the number of oscillation signals corresponding to the low-level duration is reduced by Cou2 on the original basis.

[0111] Step S3: Repeat step S2 until the signal to be adjusted SigB is consistent with the reference signal SigA, that is, the duty cycles of the two signals are the same.

[0112] Step S4: Invert the signal to be adjusted SigB to obtain a control signal, and integrate the control signal through a NEMA curve to obtain a drive signal for facilitating dimming control.

[0113] Embodiment 2

[0114] As Figure 4 shown, this embodiment provides a thyristor dimming chip, including the signal processing circuit 100 described in Embodiment 1; further, it also includes a current control circuit 200, a signal acquisition circuit 300, a capacitor charging circuit 400, a charging control circuit 500, and a voltage generation circuit 600.

[0115] Among them, the current control circuit 200 is connected between the output port OUT and the sampling port CS of the thyristor dimming chip, and is used to control the current flowing through the LED string; the signal acquisition circuit 300 is connected to the output port OUT of the thyristor dimming chip, and is used to obtain the dimming signal Dim according to the current flowing through the LED string and provide it to the signal processing circuit 100; the signal processing circuit 100 adjusts the signal to be dimmed SigB according to the dimming signal Dim to obtain the driving signal; the capacitor charging circuit 400 is connected between the control port CH and the ground port GND of the thyristor dimming chip, and adjusts the supply voltage of the LED string by establishing a capacitor charging path; the charging control circuit 500 is connected between the signal processing circuit 100 and the capacitor charging circuit 400, and is used to control whether the capacitor charging path is established according to the driving signal; the voltage generation circuit 600 is connected to the power supply port HV of the thyristor dimming chip, and is used to convert the bus voltage into the working voltage to supply power to the charging control circuit 500.

[0116] Furthermore, the thyristor dimming chip further includes an access detection circuit 700, a discharge control circuit 800 and a discharge circuit 900.

[0117] Among them, the access detection circuit 700 is used to detect whether a thyristor is accessed; the discharge circuit 800 is connected between the discharge port BLEED of the thyristor dimming chip and the reference ground, and the discharge control circuit 800 is connected between the phase-cut detection circuit 700 and the discharge circuit 800, and is used to control the discharge circuit 800 to establish a discharge path when a thyristor is accessed.

[0118] In summary, a method for processing a dimming signal, a signal processing circuit and a thyristor dimming chip according to the present invention use a signal processing circuit to replace an off-chip integration capacitor circuit to process the dimming signal, which can completely solve the problem of output current ripple; moreover, the signal processing circuit can be integrated inside the thyristor dimming chip, which reduces the area and power consumption of the system circuit and improves the stability and integration of the system circuit on the premise of ensuring good working performance of the circuit. Therefore, the present invention effectively overcomes various disadvantages in the prior art and has high industrial utilization value.

[0119] The above embodiments are only illustrative of the principles and effects of the present invention and are not used to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A signal processing circuit, characterized in that, The signal processing circuit includes: a conversion module, a comparison module, an adjustment module, and a storage module; The conversion module receives a dimming signal and converts the dimming signal into a square wave signal to obtain a reference signal; the comparison module is connected to the conversion module and is configured to compare the reference signal with a signal to be adjusted read from the storage module; The adjustment module is connected to the comparison module and starts to work under the control of the comparison result output by the comparison module. It is configured to read the reference signal and the signal to be adjusted from the storage module, and adjust the signal to be adjusted according to the difference in the high-level duration of the two signals; The storage module is connected to the conversion module, the comparison module, and the adjustment module, and is configured to store a preset square wave signal and provide it as the initial signal to be adjusted to the comparison module and the adjustment module, and store the reference signal output by the conversion module and the signal to be adjusted output by the adjustment module.

2. The signal processing circuit according to claim 1, wherein The conversion module includes a comparator and an inverter; the positive input terminal of the comparator is connected to the dimming signal, the negative input terminal is connected to a reference signal, the output terminal is connected to the input terminal of the inverter, and the output terminal of the inverter outputs the reference signal.

3. The signal processing circuit according to claim 1, wherein The adjustment module includes a first adjustment unit and a second adjustment unit; The first adjustment unit starts to work when the reference signal is less than the signal to be adjusted. It is configured to read the reference signal and the signal to be adjusted from the storage module, obtain the difference in the high-level duration of the two signals as an adjustment amount, and perform signal adjustment by subtracting the adjustment amount from the high-level duration of the signal to be adjusted; the second adjustment unit starts to work when the reference signal is greater than the signal to be adjusted. It is configured to read the reference signal and the signal to be adjusted from the storage module, obtain the difference in the high-level duration of the two signals as an adjustment amount, and perform signal adjustment by adding the adjustment amount to the high-level duration of the signal to be adjusted.

4. The signal processing circuit according to claim 3, wherein The adjustment module further includes a counting unit, which is triggered by the comparison result output by the comparison module and is configured to count the adjustment times of the signal to be adjusted.

5. The signal processing circuit according to claim 1, characterized in that, The signal processing circuit further includes a shaping module, which is connected between the comparison module and the storage module and is configured to perform waveform shaping on the signal to be adjusted output by the storage module.

6. The signal processing circuit according to claim 1, wherein The signal processing circuit further includes a drive control module, which is connected to the storage module and is configured to read the signal to be adjusted from the storage module, perform an inversion process on the signal to be adjusted to obtain a control signal, and obtain a drive signal by integrating the control signal according to the NEMA curve.

7. A method for processing a dimming signal, characterized in that The processing method includes: Step S1: Convert the dimming signal into a square wave signal to obtain a reference signal; Step S2: Read the signal to be adjusted, compare the reference signal with the signal to be adjusted, and adjust the signal to be adjusted according to the difference in the high-level duration of the two signals.

8. The method for processing a dimming signal according to claim 7, wherein The method for obtaining the reference signal includes: Convert the dimming signal into the square wave signal according to the reference signal, and perform an inversion process on the square wave signal to obtain the reference signal.

9. The method for processing a dimming signal according to claim 7, wherein The method for adjusting the signal to be adjusted includes: If the reference signal is less than the signal to be adjusted, then: obtain the difference in the high-level duration of the two signals as the adjustment amount, and perform a subtraction operation on the high-level duration of the signal to be adjusted and the adjustment amount to adjust the signal; if the reference signal is greater than the signal to be adjusted, then: obtain the difference in the high-level duration of the two signals as the adjustment amount, and perform an addition operation on the high-level duration of the signal to be adjusted and the adjustment amount to adjust the signal.

10. The method for processing a dimming signal according to any one of claims 7-9, characterized in that, The processing method further includes: Step S3: Repeat step S2 until the signal to be adjusted is consistent with the reference signal.

11. The method for processing a dimming signal according to claim 10, wherein The processing method further includes: Step S4: Perform an inversion process on the signal to be adjusted to obtain a regulated signal, and obtain a drive signal by integrating the regulated signal with a NEMA curve.

12. A thyristor dimming chip, characterized in that, The thyristor dimming chip includes the signal processing circuit according to any one of claims 1-6.

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