Control circuit, method and display module for dot matrix LED display

Abstract

The application provides a dot matrix LED display control circuit, method and display module, and relates to the technical field of display. The dot matrix LED display control circuit comprises a plurality of column drive circuits, a plurality of row scanning drive circuits, a voltage-controlled frequency modulation output circuit and a controller; the controller is connected with one end of a plurality of columns of LEDs in the display through the plurality of column drive circuits; the controller is connected with the plurality of row scanning drive circuits through the voltage-controlled frequency modulation output circuit, so that the voltage-controlled frequency modulation output circuit outputs waveform signals with frequencies corresponding to voltage signals output by the controller to the plurality of row scanning drive circuits; and the plurality of row scanning drive circuits are connected with the other end of a plurality of rows of LEDs in the display, so that a target row scanning drive circuit provides a high-level signal to one end of a target row of LEDs. The selective row scanning is realized without starting from the first row and scanning row by row from top to bottom, and the local display refresh frequency of the display is dynamically improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display, in particular to a dot matrix LED display control circuit, method and display module. BACKGROUND

[0002] LED (Light Emitting Diode) display is a display screen for displaying various information such as text, graphics and animation by controlling semiconductor LED display. LED display is a flat display screen composed of LED dot matrix modules or pixel units.

[0003] In the related art, for LED display, the dot matrix LED display control circuit includes a column drive chip, a plurality of row scanning drive circuits and a single-chip microcomputer. The single-chip microcomputer is connected with the display and the plurality of row scanning drive circuits through the column drive chip. Each row scanning drive circuit is connected with one row of LEDs of the display. The single-chip microcomputer sends control signals to the column drive chip and sends pulse signals to the row scanning drive circuit. The selected diodes in the first row, the selected diodes in the second row and so on are sequentially lighted from top to bottom.

[0004] However, in the related art, the entire display can only be scanned from the first row to the bottom row row by row. The scanning process has poor flexibility, which can easily lead to low refresh frequency of the display. SUMMARY

[0005] The present application aims to solve the above technical problems in the related art by providing a dot matrix LED display control circuit, method and display module.

[0006] To achieve the above object, the technical solutions adopted by the embodiments of the present application are as follows:

[0007] In a first aspect, the embodiments of the present application provide a dot matrix LED display control circuit, which includes a plurality of column drive circuits, a plurality of row scanning drive circuits, a voltage-controlled frequency modulation output circuit and a controller.

[0008] The controller is connected with one end of a plurality of columns of LEDs in the display through the plurality of column drive circuits.

[0009] The controller is connected with a plurality of the row scanning driving circuits through the voltage-controlled frequency modulation output circuit, so that the voltage-controlled frequency modulation output circuit outputs a waveform signal with a frequency corresponding to a voltage signal output by the controller to a plurality of the row scanning driving circuits; and each of the plurality of the row scanning driving circuits is connected with another end of a plurality of rows of LEDs in the display, so that a target row scanning driving circuit provides a high-level signal to one end of a target row of LEDs.

[0010] The different row scanning driving circuits have different band-pass filtering center frequencies; the target row scanning driving circuit is a row scanning driving circuit in the plurality of the row scanning driving circuits, which has a band-pass filtering center frequency resonating with the frequency of the waveform signal; and the target row of LEDs is a row of LEDs connected with the target row scanning driving circuit.

[0011] Optionally, the row scanning driving circuit comprises a band-pass filtering circuit and a switching circuit; the band-pass filtering center frequency of the band-pass filtering circuit is the band-pass filtering center frequency of the row scanning driving circuit; one end of the switching circuit is connected with a preset power supply, and the other end of the switching circuit is connected with the other end of the corresponding row of LEDs.

[0012] The voltage-controlled frequency modulation output circuit is connected with an input end of the band-pass filtering circuit, and an output end of the band-pass filtering circuit is connected with a control end of the switching circuit, so that the waveform signal resonates with the band-pass filtering center frequency of the band-pass filtering circuit to control the one end and the other end of the switching circuit to be conductive.

[0013] Optionally, the row scanning driving circuit further comprises a rectifier circuit; the output end of the band-pass filtering circuit is connected with the control end of the switching circuit through the rectifier circuit.

[0014] Optionally, the band-pass filtering circuit comprises a first resistor, a first capacitor, a first operational amplifier, a second resistor, a third resistor, and a second capacitor.

[0015] The first resistor is connected with the negative input end of the first operational amplifier through the first capacitor, the positive input end of the first operational amplifier is grounded, and the first resistor is further grounded through the second resistor; the first resistor is further connected with the output end of the first operational amplifier through the second capacitor, the negative input end of the first operational amplifier is connected with the output end of the first operational amplifier through the third resistor, and the output end of the band-pass filtering circuit is the output end of the first operational amplifier.

[0016] Optionally, the rectifier circuit comprises a third capacitor, a first diode, a second diode, and a fourth capacitor.

[0017] The output end of the band-pass filter circuit is connected with the third capacitor, the negative electrode of the third capacitor is connected with the first diode, the positive electrode of the first diode is grounded, the positive electrode of the third capacitor is further connected with the positive electrode of the second diode, the negative electrode of the second diode is grounded through the fourth capacitor, and the negative electrode of the second diode is the output end of the rectifier circuit.

[0018] Optionally, the switch circuit comprises a first switch tube, a second switch tube and a fourth resistor, the bias end of the first switch tube is the control end of the switch circuit, one end of the first switch tube is connected with the preset power supply through the fourth resistor, and the other end of the first switch tube is grounded.

[0019] One end of the first switch tube is connected with the bias end of the second switch tube, one end of the second switch tube is connected with the preset power supply, and the other end of the second switch tube is connected with the other end of the corresponding row of LEDs.

[0020] Optionally, the first switch tube is an N-channel field effect tube, the bias end of the first switch tube is the gate of the N-channel field effect tube, one end of the first switch tube is the drain of the N-channel field effect tube, and the other end of the first switch tube is the source of the N-channel field effect tube.

[0021] The second switch tube is a P-channel field effect tube, the bias end of the second switch tube is the gate of the P-channel field effect tube, one end of the second switch tube is the source of the P-channel field effect tube, and the other end of the second switch tube is the drain of the P-channel field effect tube.

[0022] Optionally, the voltage-controlled frequency modulation output circuit and the plurality of column drive circuits are integrated in a column drive chip.

[0023] In a second aspect, the embodiment of the present application further provides a control method of a dot matrix LED display, which is applied to a controller in the control circuit of the dot matrix LED display in the first aspect, and the method comprises the following steps:

[0024] Sending a control signal to a target column drive circuit in the plurality of column drive circuits to control a target column of LEDs in the display connected with the target column drive circuit;

[0025] Sending a voltage signal to the voltage-controlled frequency modulation output circuit, so that the voltage-controlled frequency modulation output circuit outputs a waveform signal with a frequency corresponding to the voltage signal to the plurality of row scanning drive circuits based on the voltage signal, and a target row scanning drive circuit provides a high-level signal to one end of a target row of LEDs.

[0026] The different row scanning drive circuits have different band-pass filter center frequencies; the target row scanning drive circuit is a row scanning drive circuit in the plurality of row scanning drive circuits that has a band-pass filter center frequency that resonates with the frequency of the waveform signal; and the target row LED is a row of LEDs connected to the target row scanning drive circuit.

[0027] In a third aspect, the embodiments of the present application further provide a display module, comprising a display and the control circuit of the dot-matrix LED display according to any one of the first aspect.

[0028] The plurality of column drive circuits in the control circuit of the dot-matrix LED display are respectively connected to one end of a plurality of columns of LEDs in the display, and the plurality of row scanning drive circuits in the control circuit of the dot-matrix LED display are respectively connected to the other end of a plurality of rows of LEDs in the display.

[0029] The control circuit of the dot-matrix LED display provided by the embodiments of the present application comprises a plurality of column drive circuits, a plurality of row scanning drive circuits, a voltage-controlled frequency modulation output circuit and a controller; the controller is connected to one end of a plurality of columns of LEDs in the display through the plurality of column drive circuits; the controller is connected to the plurality of row scanning drive circuits through the voltage-controlled frequency modulation output circuit, so that the voltage-controlled frequency modulation output circuit outputs a waveform signal with a frequency corresponding to a voltage signal output by the controller to the plurality of row scanning drive circuits; the plurality of row scanning drive circuits are respectively connected to the other end of a plurality of rows of LEDs in the display, so that a target row scanning drive circuit provides a high-level signal to one end of a target row LED; different row scanning drive circuits have different band-pass filter center frequencies; the target row scanning drive circuit is a row scanning drive circuit in the plurality of row scanning drive circuits that has a band-pass filter center frequency that resonates with the frequency of the waveform signal; and the target row LED is a row of LEDs connected to the target row scanning drive circuit. The voltage-controlled frequency modulation output circuit outputs a waveform signal with a frequency corresponding to a voltage signal to the plurality of row scanning drive circuits, so that a target row scanning drive circuit that resonates with the frequency of the waveform signal provides a high-level signal to one end of a target row LED, without the need to scan row by row from the first row to the bottom, thereby realizing selective row scanning and dynamically improving the local display refresh frequency of the display. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some of the embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0031] Figure 1A structural schematic diagram of a control circuit of a dot matrix LED display provided by an embodiment of the present application is shown in FIG. 1.

[0032] Figure 2 A structural schematic diagram of a dot matrix LED display provided by an embodiment of the present application is shown in FIG. 1.

[0033] Figure 3 A partial structural schematic diagram of a control circuit of a dot matrix LED display provided by an embodiment of the present application is shown in FIG. 2.

[0034] Figure 4 A structural schematic diagram of a row scanning driving circuit provided by an embodiment of the present application is shown in FIG. 3.

[0035] Figure 5 A structural schematic diagram of a row scanning driving circuit provided by an embodiment of the present application is shown in FIG. 3.

[0036] Figure 6 A structural schematic diagram of a control circuit of a dot matrix LED display provided by an embodiment of the present application is shown in FIG. 1.

[0037] Figure 7 A structural schematic diagram of a voltage-controlled frequency modulation output circuit provided by an embodiment of the present application is shown in FIG. 4.

[0038] Figure 8 A flowchart of a control method of a dot matrix LED display provided by an embodiment of the present application is shown in FIG. 5.

[0039] Figure 9 A time-frequency diagram of row scanning in a related art provided by an embodiment of the present application is shown in FIG. 6.

[0040] Figure 10 A time-frequency diagram of row scanning provided by an embodiment of the present application is shown in FIG. 7.

[0041] Figure 11 A time-frequency diagram of row scanning provided by an embodiment of the present application is shown in FIG. 7.

[0042] Figure 12 A structural schematic diagram of a controller provided by an embodiment of the present application is shown in FIG. 8. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application.

[0044] The following detailed description of embodiments of the application in the drawings provided in the accompanying drawings is not intended to limit the scope of the application claimed, but merely represents selected embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the application.

[0045] In the description of the present application, it should be noted that if the terms "upper", "lower", etc. indicate the orientation or position relationship shown in the drawings, or the orientation or position relationship when the product of the application is used, it is only for the convenience of describing the application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the application.

[0046] In addition, the terms "first", "second", etc. in the specification and claims of the present application and the above drawings are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device that includes a series of steps or units does not have to be limited to those steps or units clearly listed, but can include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0047] It should be noted that the features in the embodiments of the present application can be combined with each other without conflict.

[0048] In the related art, the entire display can only be scanned from the first row to the bottom row row by row, the scanning process has poor flexibility, and is prone to cause the problem of low refresh frequency of the display.

[0049] In view of the above technical problems existing in the related art, the embodiments of the present application provide a control circuit of a dot matrix LED display, a voltage-controlled frequency modulation output circuit outputs a waveform signal of a frequency corresponding to a voltage signal output by a controller to a plurality of row scanning drive circuits, different row scanning drive circuits have different bandpass filter center frequencies, and a target row scanning drive circuit resonates with the frequency of the waveform signal to provide a high-level signal to one end of a target row LED. In combination with the control of the plurality of column drive circuits by the controller, some LEDs in the target row LED can be directly controlled to emit light, without scanning from the first row to the bottom row row by row, selective row scanning is achieved, and the local display refresh frequency of the display is dynamically improved.

[0050] The following explains a control circuit of a dot matrix LED display provided by an embodiment of the present application.

[0051] Figure 1 A structural schematic diagram of a control circuit of a dot matrix LED display provided by an embodiment of the present application is shown in FIG. 1. The control circuit of the dot matrix LED display can include a plurality of column drive circuits 101, a plurality of row scan drive circuits 102, a voltage-controlled frequency modulation output circuit 103, and a controller 104. Figure 1

[0052] The controller 104 is connected to one end of a plurality of columns of LEDs in a display 105 through the plurality of column drive circuits 101. The display 105 can be a dot matrix LED display.

[0053] In addition, the controller 104 is connected to the plurality of row scan drive circuits 102 through the voltage-controlled frequency modulation output circuit 103, so that the voltage-controlled frequency modulation output circuit 103 outputs a waveform signal of a frequency corresponding to a voltage signal output by the controller 104 to the plurality of row scan drive circuits 102; and the plurality of row scan drive circuits 102 are connected to the other end of a plurality of rows of LEDs in the display 105, so that a target row scan drive circuit 102 provides a high-level signal to one end of a target row of LEDs.

[0054] Different row scan drive circuits 102 have different band-pass filter center frequencies; the target row scan drive circuit 102 is a row scan drive circuit 102 in the plurality of row scan drive circuits 102 whose band-pass filter center frequency resonates with the frequency of the waveform signal; and the target row of LEDs is a row of LEDs connected to the target row scan drive circuit 102.

[0055] In some embodiments, the controller 104 sends a voltage signal to the voltage-controlled frequency modulation output circuit 103; the voltage-controlled frequency modulation output circuit 103 can receive the voltage signal and output a waveform signal of a frequency corresponding to the voltage signal to the plurality of row scan drive circuits 102; the plurality of row scan drive circuits 102 can receive the waveform signal, and a target row scan drive circuit 102 in the plurality of row scan drive circuits 102 whose band-pass filter center frequency resonates with the frequency of the waveform signal can provide a high-level signal to one end of a target row of LEDs, thereby achieving scanning from the target row of LEDs.

[0056] In addition, the controller 104 can also send a control signal to a target column drive circuit 101 in the plurality of column drive circuits 101 to control a target column of LEDs, so that the row scan drive circuit 102 connected to one LED outputs a high level and the column scan drive circuit connected to the LED outputs a low level, and the LED is lit up.

[0057] ​Figure 2 A schematic structural diagram of a dot matrix LED display provided by an embodiment of the present application is shown in FIG. 1. As shown in the figure, the display 105 can include multiple rows of LEDs and multiple columns of LEDs, each row of LEDs being connected to a row scanning driving circuit 102, and each column of LEDs being connected to a column scanning driving circuit. In addition, only 8 rows of LEDs and 8 columns of LEDs are shown in the figure, and it should be understood that this is only an example, and the number of rows and columns of LEDs in the display 105 is not specifically limited in the embodiment of the present application. Figure 2

[0058] For example, for an LED in the first row and the first column, if the row scanning driving circuit 102 connected to the LED in the first row sends a high-level signal to the LED in the first row, and the column scanning circuit connected to the LED in the first column sends a low-level signal to the LED in the first column, the LED in the first row and the first column emits light.

[0059] It should be noted that the voltage signal can be a signal in a preset voltage range, for example, the preset voltage range can be 0-3.3V (volts), and different voltage signals in the preset voltage range can be input into the voltage-controlled frequency modulation output circuit 103, and the voltage-controlled frequency modulation output circuit 103 can output waveform signals with different frequencies, and the frequency of the waveform signal can be between 1 megahertz and 3 megahertz.

[0060] Correspondingly, different row scanning driving circuits 102 have different bandpass filter center frequencies, for example, the bandpass filter center frequencies of every two row scanning driving circuits 102 are spaced 1 kilohertz apart, and then a display screen with 2000 rows can be driven, and the bandpass filter center frequencies of the 2000 driving circuits can be adjusted to 1.001 megahertz, 1.002 megahertz, 1.003 megahertz, …, 2.999 megahertz, and 3.000 megahertz, respectively.

[0061] ​In summary, this invention provides a control circuit for a dot-matrix LED display, comprising: multiple column driving circuits, multiple row scanning driving circuits, a voltage-controlled frequency modulation (VDC) output circuit, and a controller; the controller is connected to one end of multiple columns of LEDs in the display through the multiple column driving circuits; the controller is connected to the multiple row scanning driving circuits through the VDC output circuit, so that the VDC output circuit outputs a waveform signal of the frequency corresponding to the voltage signal to the multiple row scanning driving circuits based on the voltage signal output by the controller; the multiple row scanning driving circuits are connected to the other end of multiple rows of LEDs in the display, so that the target row scanning driving circuit provides a high-level signal to one end of the target row LED; wherein, different row scanning driving circuits have different bandpass filter center frequencies; the target row scanning driving circuit is a row scanning driving circuit whose bandpass filter center frequency resonates with the frequency of the waveform signal among the multiple row scanning driving circuits, and the target row LED is a row of LEDs connected to the target row scanning driving circuit. By using a voltage-controlled frequency modulation output circuit to output waveform signals of the frequency corresponding to the voltage signals to multiple line scanning drive circuits, the target line scanning drive circuit that resonates with the frequency of the waveform signal provides a high-level signal to one end of the target line LED. This eliminates the need to scan line by line from top to bottom starting from the first line, achieving selective line scanning and dynamically improving the local display refresh rate of the display.

[0062] Optional, Figure 3 This is a partial structural diagram of a control circuit for a dot-matrix LED display provided in an embodiment of the present invention, as shown below. Figure 3 As shown, the row scanning drive circuit 102 includes: a bandpass filter circuit 1021 and a switching circuit 1022; the bandpass filter center frequency of the bandpass filter circuit 1021 is the same as the bandpass filter center frequency of the row scanning drive circuit 102; one end of the switching circuit 1022 is connected to a preset power supply, and the other end of the switching circuit 1022 is connected to the other end of the corresponding row LED.

[0063] The voltage-controlled frequency modulation output circuit 103 is connected to the input terminal of the bandpass filter circuit 1021, and the output terminal of the bandpass filter circuit 1021 is connected to the control terminal of the switching circuit 1022, so that after the waveform signal resonates with the center frequency of the bandpass filter of the bandpass filter circuit 1021, one end of the control switching circuit 1022 and the other end are turned on.

[0064] In some implementations, the voltage-controlled frequency modulation output circuit 103 outputs a waveform signal to the bandpass filter circuit 1021. If the waveform signal resonates with the center frequency of the bandpass filter of the bandpass filter circuit 1021, the bandpass filter circuit 1021 outputs a target waveform to the control terminal of the switching circuit 1022. The switching circuit 1022 controls one end and the other end of the switching circuit 1022 to be turned on according to the target waveform. The other end of the switching circuit 1022 outputs a high-level signal to the other end of the corresponding row LED.

[0065] It should be noted that different band-pass filter circuits 1021 can select components with different parameters, so that different band-pass filter circuits 1021 have different band-pass filter center frequencies, so that different row scanning drive circuits 102 have different band-pass filter center frequencies.

[0066] Optionally, Figure 4 A structural schematic diagram of a row scanning drive circuit provided by an embodiment of the present application is shown in FIG. 2. Figure 4 As shown in FIG. 2, the row scanning drive circuit 102 further includes a rectifier circuit 1023; and an output end of the band-pass filter circuit 1021 is connected to a control end of the switch circuit 1022 through the rectifier circuit 1023.

[0067] In the embodiment of the present application, the band-pass filter circuit 1021 can output a target waveform to the rectifier circuit 1023, the rectifier circuit 1023 can perform rectification filtering processing on the target waveform, and output the rectification filtered target waveform to the control end of the switch circuit 1022; the switch circuit 1022 controls one end and the other end of the switch circuit 1022 to be conductive according to the rectification filtered target waveform, and the other end of the switch circuit 1022 outputs a high-level signal to the other end of the corresponding row LED.

[0068] Optionally, Figure 5 A structural schematic diagram of a row scanning drive circuit provided by an embodiment of the present application is shown in FIG. 2. Figure 5 As shown in FIG. 2, the band-pass filter circuit 1021 includes a first resistor R1, a first capacitor C1, a first operational amplifier Q1, a second resistor R2, a third resistor R3, and a second capacitor C2.

[0069] The first resistor R1 is connected to the negative input end of the first operational amplifier Q1 through the first capacitor C1, the positive input end of the first operational amplifier Q1 is grounded, and the first resistor R1 is also grounded through the second resistor R2; the first resistor R1 is also connected to the output end of the first operational amplifier Q1 through the second capacitor C2, the negative input end of the first operational amplifier Q1 is connected to the output end of the first operational amplifier Q1 through the third resistor R3, and the output end of the band-pass filter circuit 1021 is the output end of the first operational amplifier Q1.

[0070] In the embodiment of the present application, the first resistor R1, the first capacitor C1, the second resistor R2 and the second capacitor C2 can constitute an RC (resistor-capacitor) oscillation circuit, the first resistor R1, the first capacitor C1, the second resistor R2 and the second capacitor C2 are set to different values, the band-pass filter circuit 1021 can obtain different band-pass filter center frequencies, and the values of the first resistor R1, the first capacitor C1, the second resistor R2 and the second capacitor C2 in the band-pass filter circuit 1021 of the different row scanning driving circuits 102 can be different. For example, the band-pass filter center frequency can be between 1 megahertz and 3 megahertz.

[0071] In addition, the first operational amplifier Q1 is used to amplify and output the target waveform to the rectified current.

[0072] Optionally, as shown in Figure 5 The rectifier circuit 1023 includes a third capacitor C3, a first diode D1, a second diode D2 and a fourth capacitor C4.

[0073] The output end of the band-pass filter circuit 1021 is connected with the third capacitor C3, the negative electrode of the first diode D1 is connected with the third capacitor C3, the positive electrode of the first diode is grounded, the positive electrode of the second diode D2 is also connected with the third capacitor C3, the negative electrode of the second diode D2 is grounded through the fourth capacitor C4, and the negative electrode of the second diode D2 is the output end of the rectifier circuit 1023.

[0074] It should be noted that the rectifier circuit 1023 composed of the third capacitor C3, the first diode D1, the second diode D2 and the fourth capacitor C4 can rectify and filter the target waveform output by the band-pass filter circuit 1021, and output the rectified and filtered target waveform to the control end of the switch circuit 1022.

[0075] Optionally, as shown in Figure 5 The switch circuit 1022 includes a first switch tube Q2, a second switch tube Q3 and a fourth resistor R4, the bias end of the first switch tube Q2 is the control end of the switch circuit 1022, one end of the first switch tube Q2 is connected with a preset power supply through the fourth resistor R4, and the other end of the first switch tube Q2 is grounded.

[0076] One end of the first switch tube Q2 is connected with the bias end of the second switch tube Q3, one end of the second switch tube Q3 is connected with the preset power supply, and the other end of the second switch tube Q3 is connected with the other end of the corresponding row LED.

[0077] The fourth resistor R4 is a load resistor.

[0078] In some embodiments, the rectifier circuit 1023 outputs the rectified and filtered target waveform to the bias end of the first switch tube Q2, and one end of the first switch tube Q2 can output a signal to the bias end of the second switch tube Q3, so that the second switch tube Q3 is turned on. Since one end of the second switch tube Q3 is connected to the preset power supply, the other end of the second switch tube Q3 outputs a high-level signal.

[0079] In addition, as shown in Figure 5 , the switch circuit 1022 can further include a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, and an eighth resistor R8. The negative electrode of the second diode D2 in the rectifier circuit 1023 is connected to the bias end of the first switch tube Q2 through the fifth resistor R5, and the bias end of the first switch tube Q2 is further connected to the ground through the sixth resistor R6. One end of the first switch tube Q2 is connected to the bias end of the second switch tube Q3 through the seventh resistor R7, and the bias end of the second switch tube Q3 is further connected to the preset power supply through the eighth resistor R8.

[0080] It should be noted that the fifth resistor R5 is a driving protection resistor of the first switch tube Q2, the seventh resistor R7 is a driving protection resistor of the second switch tube Q3, and the sixth resistor R6 and the eighth resistor R8 are discharge resistors. In addition, as shown in Figure 5 , the preset power supply can be represented as VCC.

[0081] Optionally, the first switch tube is an N-channel field effect tube, the bias end of the first switch tube is the gate of the N-channel field effect tube, one end of the first switch tube is the drain of the N-channel field effect tube, and the other end of the first switch tube is the source of the N-channel field effect tube.

[0082] The second switch tube is a P-channel field effect tube, the bias end of the second switch tube is the gate of the P-channel field effect tube, one end of the second switch tube is the source of the P-channel field effect tube, and the other end of the second switch tube is the drain of the P-channel field effect tube.

[0083] Optionally, Figure 6 A structure diagram of a control circuit of a dot matrix LED display provided by an embodiment of the present application is shown in Figure 6 , the voltage-controlled frequency modulation output circuit 103 and the plurality of column drive circuits 101 are integrated in a column drive chip.

[0084] Optionally, Figure 7 A structure diagram of a voltage-controlled frequency modulation output circuit provided by an embodiment of the present application is shown in Figure 7As shown, the voltage-controlled frequency modulation output circuit 103 comprises: the voltage-controlled frequency modulation output circuit comprises: a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a fifth capacitor C5, a second operational amplifier Q4, a thirteenth resistor R13, a fourteenth resistor R14, a third operational amplifier Q5, a fifteenth resistor R15, and a transistor T1.

[0085] The controller 104 is connected with the fifth capacitor C5 through the ninth resistor R9, the fifth capacitor C5 is connected with the output end of the second operational amplifier Q4, the negative input end of the second operational amplifier Q4 is connected with the first end of the transistor T1 through the eleventh resistor R11, the controller 104 is also connected with the positive input end of the second operational amplifier Q4 through the tenth resistor R10, and the positive input end of the second operational amplifier Q4 is also grounded through the twelfth resistor R12.

[0086] The output end of the second operational amplifier Q4 is connected with the negative input end of the third operational amplifier Q5, the positive input end of the third operational amplifier Q5 is grounded through the thirteenth resistor R13, the output end of the third operational amplifier Q5 is connected with the positive input end of the third operational amplifier Q5 through the fourteenth resistor R14, the output end of the third operational amplifier Q5 is connected with the second end of the transistor T1 through the fifteenth resistor R15, the third end of the transistor T1 is grounded, and the output end of the third operational amplifier Q5 is connected with a plurality of row scanning drive circuits.

[0087] In the embodiment of the present application, the voltage-controlled frequency modulation output circuit 103 can also be referred to as a VCO (Voltage Controlled Oscillator), and the second operational amplifier Q4 can be used as an integrator. When the transistor T1 is in the on state, the current flowing out of the ninth resistor R9 passes through the field effect transistor, the tenth resistor R10 has a resistance value generally the same as that of the ninth resistor R9, the voltage drop is the same, the current of the tenth resistor R10 is twice that of the ninth resistor R9, and the additional current charges the fifth capacitor C5. The second operational amplifier Q4 provides a gradually increasing output voltage to provide the current.

[0088] In addition, when the transistor T1 is in the off state, the current flowing out of the ninth resistor R9 is discharged through the fifth capacitor C5, so that the output voltage of the second operational amplifier Q4 decreases, and the second operational amplifier Q4 can output a triangular wave.

[0089] It should be noted that the third operational amplifier Q5 operates as a Schmitt trigger. The input of the third operational amplifier Q5 is the triangular wave, that is, the output of the second operational amplifier Q4. If the input voltage of the third operational amplifier Q5 is higher than the threshold level, the output of the third operational amplifier Q5 will be high. If the input voltage of the third operational amplifier Q5 is lower than the threshold level, the output of the third operational amplifier Q5 will be zero. Therefore, the output of the third operational amplifier Q5 is a square wave.

[0090] In the embodiment of the present application, when the input voltage signal is different, the voltage-controlled frequency modulation output circuit 103 outputs square waves of different frequencies, that is, waveform signals of different frequencies.

[0091] The embodiment of the present application provides a control method of a dot matrix LED display, which is applied to a controller in a control circuit of the dot matrix LED display. The control method of the dot matrix LED display provided by the embodiment of the present application is explained and described below.

[0092] Optionally, Figure 8 A flowchart of the control method of the dot matrix LED display provided by the embodiment of the present application is shown in FIG. 1, and the method comprises the following steps. Figure 8

[0093] S101, a control signal is sent to a target column drive circuit in a plurality of column drive circuits, so as to control a target column LED in a display connected to the target column drive circuit.

[0094] S102, a voltage signal is sent to a voltage-controlled frequency modulation output circuit, so that the voltage-controlled frequency modulation output circuit outputs a waveform signal of a frequency corresponding to the voltage signal to a plurality of row scanning drive circuits based on the voltage signal, so that a target row scanning drive circuit provides a high-level signal to one end of a target row LED.

[0095] Different row scanning drive circuits have different band-pass filtering center frequencies; the target row scanning drive circuit is a row scanning drive circuit in the plurality of row scanning drive circuits, the band-pass filtering center frequency of which resonates with the frequency of the waveform signal; and the target row LED is a row of LEDs connected to the target row scanning drive circuit.

[0096] It should be noted that the specific implementation process of S101 and S102 can refer to the related description of the control circuit of the dot matrix LED display above, which will not be repeated here.

[0097] ​To sum up, the embodiment of the present application provides a control method of a dot matrix LED display, which comprises the following steps: sending a control signal to a target column drive circuit in a plurality of column drive circuits, so as to control a target column LED in the display connected to the target column drive circuit; and sending a voltage signal to a voltage-controlled frequency modulation output circuit, so that the voltage-controlled frequency modulation output circuit outputs a waveform signal with a frequency corresponding to the voltage signal to a plurality of row scanning drive circuits, so that a target row scanning drive circuit provides a high-level signal to one end of a target row LED; wherein different row scanning drive circuits have different band-pass filtering center frequencies; the target row scanning drive circuit is a row scanning drive circuit in the plurality of row scanning drive circuits, which resonates with the frequency of the waveform signal; and the target row LED is a row of LEDs connected to the target row scanning drive circuit. The controller outputs the voltage signal to the voltage-controlled frequency modulation output circuit, so that the voltage-controlled frequency modulation output circuit outputs the waveform signal with the frequency corresponding to the voltage signal to the plurality of row scanning drive circuits, and the target row scanning drive circuit, which resonates with the frequency of the waveform signal, provides the high-level signal to one end of the target row LED, without starting from the first row and scanning row by row from top to bottom, so that selective row scanning is realized, and the local display refresh frequency of the display is dynamically improved.

[0098] Figure 9 A time-frequency diagram of row scanning in a related technology provided for the embodiment of the present application is shown in FIG. 1, wherein the horizontal axis represents time T (S, second), and the vertical axis represents modulation frequency F (M). Figure 9 As shown in FIG. 1, the display of one frame is controlled by the output of the voltage signal, so that the frequency is scanned once from low to high, wherein the horizontal axis represents time T (S, second), and the vertical axis represents modulation frequency F (M).

[0099] Figure 10 A time-frequency diagram of row scanning provided for the embodiment of the present application is shown in FIG. 2, wherein the horizontal axis represents time T (S, second), and the vertical axis represents modulation frequency F (M). Figure 10 As shown in FIG. 2, the controller controls the output of a small piece of voltage signal, so that the frequency (waveform signal) is repeated in a small range, and local fast scanning is realized, wherein the horizontal axis represents time T (S, second), and the vertical axis represents modulation frequency F (M).

[0100] Figure 11 A time-frequency diagram of row scanning provided for the embodiment of the present application is shown in FIG. 3, wherein the horizontal axis represents time T (S, second), and the vertical axis represents modulation frequency F (M). Figure 11 As shown in FIG. 3, the controller controls the output of a segmented voltage signal, so that the frequency (waveform signal) is segmented and output. Thus, segmented scanning is realized, wherein the horizontal axis represents time T (S, second), and the vertical axis represents modulation frequency F (M).

[0101] As can be seen from the above, the embodiment of the present application realizes local row scanning and selective segmented row scanning, and dynamically improves the refresh frequency of local display. The motion coherence and delicacy of the LED display are improved.

[0102] The embodiment of the present application provides a display control device, which is applied to a controller in a control circuit of a dot matrix LED display, and the device comprises the following steps:

[0103] The sending module is configured to send a control signal to a target column drive circuit in the plurality of column drive circuits, so as to control a target column LED in the display connected to the target column drive circuit; and send a voltage signal to the voltage-controlled frequency modulation output circuit, so that the voltage-controlled frequency modulation output circuit outputs a waveform signal with a frequency corresponding to the voltage signal to the plurality of row scanning drive circuits based on the voltage signal, so that the target row scanning drive circuit provides a high-level signal to one end of the target row LED; wherein different row scanning drive circuits have different band-pass filtering center frequencies; the target row scanning drive circuit is a row scanning drive circuit in the plurality of row scanning drive circuits, and the band-pass filtering center frequency of the row scanning drive circuit resonates with the frequency of the waveform signal; and the target row LED is a row of LEDs connected to the target row scanning drive circuit.

[0104] The embodiment of the present application provides a display module, which comprises a display and the control circuit of the dot matrix LED display.

[0105] The plurality of column drive circuits in the control circuit of the dot matrix LED display are respectively connected to one end of a plurality of columns of LEDs in the display, and the plurality of row scanning drive circuits in the control circuit of the dot matrix LED display are respectively connected to the other end of a plurality of rows of LEDs in the display.

[0106] In addition, the display is a dot matrix LED display.

[0107] The embodiment of the present application provides a display device, which comprises the display module and a preset power supply. The display device can be a smart phone, a tablet computer, a notebook computer and the like, and the embodiment of the present application does not specifically limit the display device.

[0108] The device is used for executing the method provided in the foregoing embodiment, and has similar implementation principles and technical effects, which will not be described in detail herein.

[0109] The above modules can be one or more integrated circuits configured to implement the above methods, for example, one or more application specific integrated circuits (ASICs), or one or more digital signal processors (DSPs), or one or more field programmable gate arrays (FPGAs), etc. For another example, when a certain module above is implemented in the form of a processing element scheduling code, the processing element can be a general purpose processor, such as a central processing unit (CPU) or other processor that can invoke code. For another example, the modules can be integrated together to implement a system-on-a-chip (SOC).

[0110] Figure 12 A structural diagram of a controller provided by an embodiment of the application is shown in FIG. 1, which includes a processor 1201 and a memory 1202. Figure 12

[0111] The memory 1202 is configured to store a program, and the processor 1201 invokes the program stored in the memory 1202 to execute the above method embodiments. The specific implementation and technical effects are similar, and will not be repeated here.

[0112] Optionally, the application further provides a program product, for example, a computer readable storage medium, including a program, which, when executed by a processor, is configured to execute the above method embodiments.

[0113] In several embodiments provided by the application, it should be understood that the disclosed apparatus and method can be implemented in other manners. For example, the described apparatus embodiments are merely schematic, and the division of units is merely a logical function division, and there can be another division manner in actual implementation. For example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections can be indirect couplings or communication connections through some interfaces, devices or units, and can be electrical, mechanical or other forms.

[0114] ​The units described as separate components may or may not be physically separate, and the components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed on multiple network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment scheme.

[0115] In addition, each functional unit in each embodiment of the application can be integrated in one processing unit, or each unit can exist physically, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of hardware plus software functional unit.

[0116] The integrated unit realized in the form of software functional unit can be stored in a computer readable storage medium. The software functional unit stored in a storage medium includes a plurality of instructions for making a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor (English: processor) execute part of the steps of the method described in each embodiment of the application. And the foregoing storage medium includes: U disk, mobile hard disk, read-only memory (English: Read-Only Memory, for short: ROM), random access memory (English: Random Access Memory, for short: RAM), magnetic disk or optical disk and various program code storage media.

[0117] The above is only the preferred embodiment of the application and is not used to limit the application. For those skilled in the art, the application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the application shall be included in the protection scope of the application.

Claims

1. A control circuit for a dot matrix LED display, characterized by The application relates to a display device, which comprises a plurality of column drive circuits, a plurality of row scanning drive circuits, a voltage-controlled frequency modulation output circuit and a controller. The controller is connected to one end of a plurality of columns of LEDs in a display through the plurality of column drive circuits. The controller is connected to the plurality of row scanning drive circuits through the voltage-controlled frequency modulation output circuit, so that the voltage-controlled frequency modulation output circuit outputs a waveform signal with a frequency corresponding to a voltage signal output by the controller to the plurality of row scanning drive circuits. The other end of a plurality of rows of LEDs in the display is connected to the plurality of row scanning drive circuits, so that a target row scanning drive circuit provides a high-level signal to one end of a target row of LEDs. Different row scanning drive circuits have different band-pass filtering center frequencies; the target row scanning drive circuit is a row scanning drive circuit in the plurality of row scanning drive circuits, which has a band-pass filtering center frequency resonating with the frequency of the waveform signal; and the target row of LEDs is a row of LEDs connected to the target row scanning drive circuit. The row scanning drive circuit comprises a band-pass filtering circuit and a switching circuit; the band-pass filtering center frequency of the band-pass filtering circuit is the band-pass filtering center frequency of the row scanning drive circuit; one end of the switching circuit is connected to a preset power supply, and the other end of the switching circuit is connected to the other end of the corresponding row of LEDs. The voltage-controlled frequency modulation output circuit is connected to the input end of the band-pass filtering circuit, and the output end of the band-pass filtering circuit is connected to the control end of the switching circuit, so that the waveform signal resonates with the band-pass filtering center frequency of the band-pass filtering circuit to control the conduction of one end and the other end of the switching circuit. The row scanning drive circuit further comprises a rectifier circuit; the output end of the band-pass filtering circuit is connected to the control end of the switching circuit through the rectifier circuit.

2. The circuit of claim 1, wherein, The band-pass filtering circuit comprises a first resistor, a first capacitor, a first operational amplifier, a second resistor, a third resistor and a second capacitor.

3. The circuit of claim 1, wherein, The first resistor is connected to the negative input end of the first operational amplifier through the first capacitor, the positive input end of the first operational amplifier is grounded, and the first resistor is further grounded through the second resistor; the first resistor is further connected to the output end of the first operational amplifier through the second capacitor, the negative input end of the first operational amplifier is connected to the output end of the first operational amplifier through the third resistor, and the output end of the band-pass filtering circuit is the output end of the first operational amplifier. The rectifier circuit comprises a third capacitor, a first diode, a second diode and a fourth capacitor.

4. The circuit of claim 2, wherein, The output end of the band-pass filtering circuit is connected to the third capacitor, the third capacitor is connected to the negative electrode of the first diode, the positive electrode of the first diode is grounded, the third capacitor is further connected to the positive electrode of the second diode, the negative electrode of the second diode is grounded through the fourth capacitor, and the negative electrode of the second diode is the output end of the rectifier circuit. ​ 5. The circuit of claim 1, wherein, The switch circuit comprises a first switch tube, a second switch tube and a fourth resistor, the bias end of the first switch tube is the control end of the switch circuit, one end of the first switch tube is connected with the preset power supply through the fourth resistor, and the other end of the first switch tube is grounded. One end of the first switch tube is connected with the bias end of the second switch tube, one end of the second switch tube is connected with the preset power supply, and the other end of the second switch tube is connected with the other end of the corresponding row of LEDs.

6. The circuit of claim 5, wherein, The first switch tube is an N-channel field effect tube, the bias end of the first switch tube is the gate of the N-channel field effect tube, one end of the first switch tube is the drain of the N-channel field effect tube, and the other end of the first switch tube is the source of the N-channel field effect tube. The second switch tube is a P-channel field effect tube, the bias end of the second switch tube is the gate of the P-channel field effect tube, one end of the second switch tube is the source of the P-channel field effect tube, and the other end of the second switch tube is the drain of the P-channel field effect tube.

7. The circuit of claim 1, wherein, The voltage-controlled frequency modulation output circuit and the plurality of column drive circuits are integrated in a column drive chip.

8. A method of controlling a dot matrix LED display, characterized by, The controller applied to the control circuit of the dot matrix LED display of any one of the above claims 1-7, the method comprises: sending a control signal to a target column drive circuit in the plurality of column drive circuits to control a target column of LEDs in the display connected to the target column drive circuit; sending a voltage signal to the voltage-controlled frequency modulation output circuit to make the voltage-controlled frequency modulation output circuit output a waveform signal of a frequency corresponding to the voltage signal to the plurality of row scanning drive circuits based on the voltage signal, so that a target row scanning drive circuit provides a high-level signal to one end of a target row of LEDs; wherein different row scanning drive circuits have different bandpass filter center frequencies; the target row scanning drive circuit is a row scanning drive circuit in the plurality of row scanning drive circuits whose bandpass filter center frequency resonates with the frequency of the waveform signal, and the target row of LEDs is a row of LEDs connected to the target row scanning drive circuit.

9. A display module, characterized by comprising: a display and the control circuit of the dot matrix LED display of any one of the above claims 1-7; a plurality of column drive circuits in the control circuit of the dot matrix LED display are respectively connected to one end of a plurality of columns of LEDs in the display, and a plurality of row scanning drive circuits in the control circuit of the dot matrix LED display are respectively connected to the other end of a plurality of rows of LEDs in the display.

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