High-voltage linear LED driver circuits and electronics

Abstract

The present application provides a high-voltage linear LED drive circuit and electronic equipment. The high-voltage linear LED drive circuit is composed of a clamping diode D1, a current reference unit, a voltage reference unit, an operational amplifier AMP, a low-voltage power tube MN1, a high-voltage power tube MN2, etc. The cathode of D1 is connected to an external power supply V IN and LED anode, and is also connected to the current reference unit, AMP voltage drive terminal, D2 cathode and MN2 gate; the AMP output terminal controls the MN1 gate, the MN1 drain is connected to the D2 anode and MN2 source, and the MN1 source is grounded through the sampling resistor R1; the MN2 drain is connected to the LED cathode; the MN1 threshold voltage V th1 Lower than MN2's V th2 , and the parasitic capacitance of MN1 gate is smaller. Based on the constant current loop formed by AMP, MN1 and R1, the conduction state of MN2 is indirectly controlled by adjusting MN1, avoiding the delay caused by directly controlling the MN2 gate. D2 and D1 cooperate to achieve overvoltage clamping protection, and can also intelligently control LED dimming based on audio.

Description

Technical Field

[0001] The present application relates to the field of electronic power technology, and in particular to a high-voltage linear LED drive circuit and electronic equipment. Background Art

[0002] Currently, in lighting systems used for film and television atmospheres, ordinary linear LED driver chips are difficult to meet the requirements of LED dimming. There are two problems: 1. Insufficient dimming linearity. When using the same PWM signal to drive multiple groups of LEDs, the response time deviation between chips is large, resulting in large current deviations between light groups driven by different chips at low brightness, resulting in large color differences; 2. The response speed corresponding to the film and television atmosphere is slow, making it difficult to dim the LED in real time according to the film and television atmosphere. Summary of the Invention

[0003] The present application provides a high-voltage linear LED driving circuit and electronic device for adjusting low-brightness LEDs, thereby improving the user experience by increasing the response speed of the LEDs to the film and television atmosphere and improving the linearity of dimming.

[0004] In a first aspect, an embodiment of the present application provides a high-voltage linear LED driving circuit, comprising: a clamping diode D1, a current reference unit, a voltage reference unit, a voltage reference driving stage unit, an operational amplifier AMP, a low-voltage power transistor MN1, a high-voltage power transistor MN2, a protection diode D2, and a sampling resistor R1;

[0005] The cathode of the clamping diode D1 is used to connect the external power supply V IN , the anode of the external LED, the cathode of the clamping diode D1 is also connected to the input end of the current reference unit, the voltage driving end of the operational amplifier AMP, the cathode of the protection diode D2, and the Gate end of the high-voltage power tube MN2 respectively; the anode of the clamping diode D1 is grounded; the output end of the current reference unit is connected to the bias current input end of the operational amplifier AMP; the output end of the voltage reference unit is connected to the input end of the voltage reference driving stage unit; the output end of the voltage reference driving stage unit is connected to the positive electrode of the operational amplifier AMP to provide a reference voltage V to the operational amplifier AMP REF The output end of the operational amplifier AMP is connected to the Gate end of the low-voltage power tube MN1; the Drain end of the low-voltage power tube MN1 is respectively connected to the anode of the protection diode D2 and the Source end of the high-voltage power tube MN2, and the Source end of the low-voltage power tube MN1 is grounded through the sampling resistor R1; the Drain end of the high-voltage power tube MN2 is used to be connected to the cathode of the external LED;

[0006] Among them, the first threshold voltage V of the Gate terminal of the low-voltage power tube MN1 is th1 is less than the second threshold voltage V of the Gate terminal of the high-voltage power tube MN2 th2 The parasitic capacitance of the Gate terminal of the low-voltage power tube MN1 is smaller than the parasitic capacitance of the Gate terminal of the high-voltage power tube MN2. The operational amplifier AMP, the low-voltage power tube MN1, and the sampling resistor R1 form a constant current loop, which indirectly controls the conduction of the high-voltage power tube MN2. The voltage reference unit is used to determine the reference voltage V according to a preset target audio file. REF The reference voltage V is generated according to the level change information REF .

[0007] In a second aspect, an embodiment of the present application provides an electronic device, which includes a high-voltage linear LED driving circuit as described in any one of the embodiments of the present application.

[0008] The embodiment of the present application provides a high-voltage linear LED driving circuit, which includes: a clamping diode D1, a current reference unit, a voltage reference unit, a voltage reference driving stage unit, an operational amplifier AMP, a low-voltage power tube MN1, a high-voltage power tube MN2, a protection diode D2 and a sampling resistor R1; the cathode of the clamping diode D1 is used to connect to the external power supply V IN , the anode of the external LED, and the cathode of the clamping diode D1 are also connected to the input end of the current reference unit, the voltage driving end of the operational amplifier AMP, the cathode of the protection diode D2, and the Gate end of the high-voltage power tube MN2 respectively; the anode of the clamping diode D1 is grounded; the output end of the current reference unit is connected to the bias current input end of the operational amplifier AMP; the output end of the voltage reference unit is connected to the input end of the voltage reference driving stage unit; the output end of the voltage reference driving stage unit is connected to the positive electrode of the operational amplifier AMP to provide a reference voltage V to the operational amplifier AMP REF The output end of the operational amplifier AMP is connected to the Gate end of the low-voltage power tube MN1; the Drain end of the low-voltage power tube MN1 is connected to the anode of the protection diode D2 and the Source end of the high-voltage power tube MN2 respectively. The Source end of the low-voltage power tube MN1 is grounded through the sampling resistor R1; the Drain end of the high-voltage power tube MN2 is used to connect to the cathode of the external LED; wherein, the first threshold voltage V of the Gate end of the low-voltage power tube MN1 th1 Less than the second threshold voltage V of the Gate terminal of the high-voltage power tube MN2 th2The parasitic capacitance of the Gate terminal of the low-voltage power tube MN1 is smaller than the parasitic capacitance of the Gate terminal of the high-voltage power tube MN2. The operational amplifier AMP, the low-voltage power tube MN1 and the sampling resistor R1 form a constant current loop, which indirectly controls the conduction of the high-voltage power tube MN2. The voltage reference unit is used to determine the reference voltage V according to the preset target audio file. REF The level change information is used to generate a reference voltage V REF Through the above method, the following technical effects are achieved: 1. This application determines the current required lighting atmosphere by controlling and analyzing the audio file of the film and television atmosphere, and converts it into executable level change information to generate a reference voltage V that can be adjusted in the circuit. REF , thereby realizing rapid changes in LED lighting with film and television atmospheres; 2. This application adopts a low-voltage power tube MN1 and a high-voltage power tube MN2 in series, and utilizes the high-voltage resistance characteristics of the high-voltage power tube MN2 to enable the entire circuit to operate in a high-voltage driven LED-related circuit, and utilizes the output current of the operational amplifier AMP to drive the low-voltage power tube MN1 to control the loop current, thereby obtaining the characteristics of both high-voltage resistance and rapid startup of the loop current, thereby improving the dimming linearity under low brightness conditions; 3. The bias current of the operational amplifier AMP adopts a bias current related to the process angle of the low-voltage power tube MN1, thereby offsetting the current response differences between chips caused by different process angles, thereby improving the consistency under low brightness conditions in a multi-chip system. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0010] Figure 1 This is a schematic diagram of the first type of LED current variation in a traditional high-voltage linear LED driver circuit;

[0011] Figure 2 This is a schematic diagram of the second LED current variation of the traditional high-voltage linear LED drive circuit;

[0012] Figure 3 A circuit diagram of a high-voltage linear LED drive circuit provided in an embodiment of the present application;

[0013] Figure 4 This is a circuit diagram of a traditional high-voltage linear LED driver circuit;

[0014] Figure 5 A circuit diagram of a current reference unit provided in an embodiment of the present application;

[0015] Figure 6 A schematic diagram of the current response of a chip with process angle deviation provided in an embodiment of the present application;

[0016] Figure 7 A schematic diagram of the current response of a chip for improving process angle deviation provided in an embodiment of the present application;

[0017] Figure 8 This is a schematic flow chart of a method for adjusting level change information provided in an embodiment of the present application. DETAILED DESCRIPTION

[0018] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0019] The flowcharts shown in the accompanying drawings are for illustrative purposes only and do not necessarily include all contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps may be decomposed, combined, or partially merged, so the actual execution order may vary depending on the actual situation.

[0020] It should also be understood that the terms used in this specification are for the purpose of describing specific embodiments only and are not intended to limit the present application. As used in this specification and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise.

[0021] It should be further understood that the term "and / or" used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0022] In current technology, at high brightness (such as Figure 1 As shown in the figure, the error caused by the current startup is very small and can be almost ignored. Ordinary linear LED driver chips can meet the linearity requirements of LED dimming, but at low brightness (such as Figure 2 As shown in the figure, since the current takes a long time to start (about 700ns), the current is triangular. When adjusting the same duty cycle, the brightness increment is inconsistent, resulting in poor dimming linearity.

[0023] like Figure 2However, at low brightness (short duty cycle), since the current takes a long time to start (about 700ns), the current presents a triangular shape. When adjusting the same duty cycle, the brightness increment is inconsistent, resulting in poor dimming linearity. When using the same PWM signal to drive multiple groups of LEDs, the response time deviation between chips is large, resulting in large current deviations between lamp groups driven by different chips at low brightness, resulting in large color differences.

[0024] See also Figure 3 , Figure 3 FIG is a circuit diagram of a high voltage linear LED driving circuit provided by an embodiment of the present application. Figure 3 As shown, the high-voltage linear LED driving circuit 100 includes: a clamping diode D1, a current reference unit 11, a voltage reference unit 12, a voltage reference driving stage unit 13, an operational amplifier AMP, a low-voltage power tube MN1, a high-voltage power tube MN2, a protection diode D2 and a sampling resistor R1.

[0025] The cathode of the clamping diode D1 is used to connect the external power supply V IN , the anode of the external LED, and the cathode of the clamping diode D1 are also connected to the input terminal of the current reference unit 11, the voltage driving terminal of the operational amplifier AMP, the cathode of the protection diode D2, and the gate terminal of the high-voltage power tube MN2. The anode of the clamping diode D1 is grounded. The output terminal of the current reference unit 11 is connected to the bias current input terminal of the operational amplifier AMP to output the reference current I Bias The output end of the voltage reference unit 12 is connected to the input end of the voltage reference driving stage unit 13 to provide the initial voltage V0 to the voltage reference driving stage unit 13. The output end of the voltage reference driving stage unit 13 is connected to the positive terminal of the operational amplifier AMP to provide the reference voltage V REF The output of the operational amplifier AMP is connected to the Gate of the low-voltage power tube MN1. The Drain of the low-voltage power tube MN1 is connected to the anode of the protection diode D2 and the Source of the high-voltage power tube MN2. The Source of the low-voltage power tube MN1 is grounded through the sampling resistor R1. The Drain of the high-voltage power tube MN2 is used to connect to the cathode of the external LED. The first threshold voltage V of the Gate of the low-voltage power tube MN1 is th1 Less than the second threshold voltage V of the Gate terminal of the high-voltage power tube MN2 th2The parasitic capacitance of the Gate terminal of the low-voltage power tube MN1 is smaller than that of the Gate terminal of the high-voltage power tube MN2. The operational amplifier AMP, the low-voltage power tube MN1, and the sampling resistor R1 form a constant current loop, which indirectly controls the conduction of the high-voltage power tube MN2 to shorten the response time of the high-voltage power tube MN2. The voltage reference unit is used to determine the reference voltage V according to the preset target audio file. REF The level change information is used to generate a reference voltage V REF .

[0026] The voltage reference unit 12 provides an initial voltage V0 to the voltage reference driving stage unit 13, and the voltage reference driving stage unit 13 performs voltage following on the initial voltage V0 to generate a reference voltage V REF The voltage reference driving stage unit 13 provides a reference voltage V for the positive electrode of the operational amplifier AMP. REF Since the negative electrode of the operational amplifier AMP will generate a feedback voltage signal with a rapid jump of hundreds of nanoseconds at the moment the constant current loop is turned on, the input voltage of the positive electrode of the operational amplifier AMP must have a certain driving capability to maintain a stable reference voltage V for the constant current loop. REF If there is no voltage reference driving stage unit 13, the initial voltage V0 is directly input to the positive electrode of the operational amplifier AMP. Due to the influence of the parasitic capacitance between the positive electrodes of the operational amplifier AMP, the initial voltage V0 is easily interfered by the constant current loop, which will cause the loop establishment time to become longer.

[0027] The operational amplifier AMP provides gain for the constant current loop of the chip and provides a transient driving current for the Gate end of the low-voltage power tube MN1. The operational amplifier AMP, the low-voltage power tube MN1 and the sampling resistor R1 together form a constant current loop. The current flowing through the low-voltage power tube MN1 is determined by the reference voltage V REF It is determined by the sampling resistor R1.

[0028] The operational amplifier AMP adjusts the Gate terminal voltage of the low-voltage power tube MN1 according to the magnitude of the current flowing through the low-voltage power tube MN1, thereby adjusting the current flowing through the low-voltage power tube MN1 so that the current flowing through the low-voltage power tube MN1 remains constant. The low-voltage power tube MN1 is an ordinary 5V NMOS tube.

[0029] like Figure 4 As shown, the traditional high-voltage linear LED drive circuit is an operational amplifier AMP that directly drives a high-voltage NMOS tube (equivalent to Figure 3 The high-voltage power tube MN2 in the 5V NMOS tube has a lower threshold voltage and smaller parasitic capacitance at the gate end, which makes the loop response faster. The current rise time of the traditional high-voltage linear LED driver is about 700ns.

[0030] The technical solution of this application can shorten the rise time of the loop current to about 140ns. The shortened rise time makes the LED current closer to the ideal square wave, improving the dimming linearity under low brightness conditions.

[0031] The Gate terminal of the high-voltage power tube MN2 is directly connected to the bias voltage VDD. The current flowing through the high-voltage power tube MN2 is equal to the current flowing through the low-voltage power tube MN1. In this way, the current flowing through the high-voltage power tube MN2 is controlled by the constant current loop.

[0032] The anode of the protection diode D2 is connected to the Source terminal of the high-voltage power tube MN2 and the Drain terminal of the low-voltage power tube MN1. The cathode of the protection diode D2 is connected to the bias voltage VDD. The protection diode D2 and the clamping diode D1 form a series clamp to clamp the voltage at the Drain terminal of the low-voltage power tube MN1, preventing high voltage from being generated at the Drain terminal of the low-voltage power tube MN1 and damaging the low-voltage power tube MN1.

[0033] The embodiment of the present application provides a high-voltage linear LED driving circuit, which includes: a clamping diode D1, a current reference unit, a voltage reference unit, a voltage reference driving stage unit, an operational amplifier AMP, a low-voltage power tube MN1, a high-voltage power tube MN2, a protection diode D2 and a sampling resistor R1; the cathode of the clamping diode D1 is used to connect to the external power supply V IN , the anode of the external LED, and the cathode of the clamping diode D1 are also connected to the input end of the current reference unit, the voltage driving end of the operational amplifier AMP, the cathode of the protection diode D2, and the Gate end of the high-voltage power tube MN2 respectively; the anode of the clamping diode D1 is grounded; the output end of the current reference unit is connected to the bias current input end of the operational amplifier AMP; the output end of the voltage reference unit is connected to the input end of the voltage reference driving stage unit; the output end of the voltage reference driving stage unit is connected to the positive electrode of the operational amplifier AMP to provide a reference voltage V to the operational amplifier AMP REF The output end of the operational amplifier AMP is connected to the Gate end of the low-voltage power tube MN1; the Drain end of the low-voltage power tube MN1 is connected to the anode of the protection diode D2 and the Source end of the high-voltage power tube MN2 respectively. The Source end of the low-voltage power tube MN1 is grounded through the sampling resistor R1; the Drain end of the high-voltage power tube MN2 is used to connect to the cathode of the external LED; wherein, the first threshold voltage V of the Gate end of the low-voltage power tube MN1 th1 Less than the second threshold voltage V of the Gate terminal of the high-voltage power tube MN2 th2The parasitic capacitance of the Gate terminal of the low-voltage power tube MN1 is smaller than the parasitic capacitance of the Gate terminal of the high-voltage power tube MN2. The operational amplifier AMP, the low-voltage power tube MN1 and the sampling resistor R1 form a constant current loop, which indirectly controls the conduction of the high-voltage power tube MN2. The voltage reference unit is used to determine the reference voltage V according to the preset target audio file. REF The level change information is used to generate a reference voltage V REF Through the above method, the following technical effects are achieved: 1. This application determines the current required lighting atmosphere by controlling and analyzing the audio file of the film and television atmosphere, and converts it into executable level change information to generate a reference voltage V that can be adjusted in the circuit. REF , so as to achieve rapid changes in LED lighting with film and television atmosphere. 2. This application adopts the method of connecting low-voltage power tube MN1 and high-voltage power tube MN2 in series, and uses the high-voltage resistance characteristics of high-voltage power tube MN2 to enable the entire circuit to operate in high-voltage driven LED related circuits, and uses the output current of operational amplifier AMP to drive low-voltage power tube MN1 to control the loop current, thereby obtaining the characteristics of being able to withstand high voltage and quickly start the loop current, thereby improving the dimming linearity under low brightness conditions. 3. The bias current of the operational amplifier AMP adopts a bias current related to the process angle of the low-voltage power tube MN1, so as to offset the current response differences between chips caused by different process angles, thereby improving the consistency under low brightness conditions in multi-chip systems.

[0034] In order to more clearly introduce the technical solution of the present application, the technical solution of the present application will be introduced through specific embodiments below. It should be noted that the specific embodiments are used to expand the technical solution of the present application, but are not intended to limit the present application.

[0035] In some embodiments, as Figure 5 As shown, the current reference unit 11 includes: a current source I1, a first current power transistor MN3, a second current power transistor MN4 and a second sampling resistor R3.

[0036] like Figure 3 and Figure 5 As shown, the input terminal of current source I1 is connected to the cathode of clamping diode D1, and the output terminal of current source I1 is connected to the Gate terminal of the first current power transistor MN3 and the Drain terminal of the second current power transistor MN4, respectively. The Drain terminal of the first current power transistor MN3 is connected to the positive electrode of the operational amplifier AMP, and the Source terminal of the first current power transistor MN3 is connected to the Gate terminal of the second current power transistor MN4 and the first terminal of the second sampling resistor R3, respectively. The second terminal of the second sampling resistor R3 and the Source terminal of the second current power transistor MN4 are both grounded.

[0037] In some embodiments, the process angle of the low-voltage power transistor MN1 , the process angle of the first current power transistor MN3 , and the process angle of the second current power transistor MN4 are all the same.

[0038] For example, the chip-to-chip difference is mainly caused by factors such as process angle deviation. The first threshold voltage V th1 The size of the parasitic capacitance at the gate end is different, and the loop response speed is different, resulting in a time difference of about 40ns in the current response between chips (such as Figure 6 As shown in the figure), at low brightness, this will cause color differences between different LEDs.

[0039] The bias current I in this application Bias =V gs4 / R3, V gs4 is the Gate voltage of the second current power tube MN4. The second current power tube MN4 and the low-voltage power tube MN1 are of the same type and are placed close to each other on the layout. Therefore, the process angles of the second current power tube MN4 and the low-voltage power tube MN1 on each chip are consistent. The bias current of the operational amplifier AMP changes with the change of the process angle of different chips.

[0040] In different process angles, when the first threshold voltage V th1 When the voltage is too low, the bias current of the operational amplifier AMP and the driving current of the low-voltage power tube MN1 are also too low. When the first threshold voltage V th1 When it is too large, the bias current of the operational amplifier and the driving current of MN1 are also too large. This design makes the consistency of the response time of different chips more convergent.

[0041] The improved inter-chip current difference response is as follows Figure 7 As shown in the figure, for chips with different process angles, the rising slope of the current with slow response is larger, and the rising slope of the current with fast response is smaller. Under the same duty cycle, the area covered by the current waveform (corresponding to the brightness of the LED) has little difference.

[0042] In some embodiments, as Figure 3 As shown, the high-voltage linear LED driving circuit 100 further includes: a current limiting resistor R2 and a filter capacitor C1.

[0043] The first end of the current limiting resistor R2 is used to connect the external power supply V IN , the anode of the external LED, the second end of the current limiting resistor R2 is connected to the cathode of the clamping diode D1, the first end of the filter capacitor C1 is connected to the cathode of the clamping diode D1, and the second end of the filter capacitor C1 is grounded.

[0044] For example, the external power supply VIN A lower bias voltage VDD is provided by the current limiting resistor R2 and the clamping diode D1, and the series current limiting resistor R2 and the filter capacitor C1 provide transient energy for the driving stage of the operational amplifier AMP, thereby achieving the purpose of fast response and stable startup. If there is no cooperation of the filter capacitor C1, when the constant current loop is started, the bias voltage VDD will have a large ringing, which will slow down the response speed of the constant current loop.

[0045] The high-voltage linear LED driver circuit 100 provided in the embodiment of the present application is also used to adjust the brightness of the usage scene in conjunction with film and television content to complete atmosphere rendering. It is usually used in occasions such as theaters or music venues to improve the user experience through dimming.

[0046] In some embodiments, see Figure 8 , Figure 8 This is a schematic flow chart of a method for adjusting level change information provided in an embodiment of the present application. Figure 8 In the method for adjusting the level change information shown, the control unit (not shown in the figure) of the high-voltage linear LED driving circuit 100 is the execution body, specifically used to perform: S101-S106.

[0047] S101: Obtain a target audio file.

[0048] S102 , performing context analysis on the target audio file through a speech analysis model to obtain context description information, the context description information including voice part of speech, voice energy value, scene part of speech, and scene energy value.

[0049] It's important to note that currently, dimming solutions for synchronized film and television content are typically handled by professionals, resulting in high costs and limited replicability. For older film and television content, or content with limited popularity, corresponding dimming solutions often don't exist, making synchronized dimming impossible in these scenarios.

[0050] With the rise of artificial intelligence, some intelligent dimming solutions based on human voice content have also emerged. However, the dimming indicators of these solutions are monotonous, making it difficult to achieve precise dimming, and often bring a worse user experience.

[0051] This application uses the energy values of both human voices and ambient sounds to perform a multi-dimensional scoring to identify the specific factors that determine the current atmosphere. The emotions expressed by human voices and ambient sounds can be synchronized (non-differential intervals) or disjointed (conflicting intervals). A calm human voice can contain intense ambient expressions, while a weeping human voice can contain joyful ambient expressions. These conflicting information often leads to misclassification of emotion by the model. Different evaluation criteria are required for different scenarios, and these need to be differentiated.

[0052] S103. If the vocal part of speech and the scene part of speech are in the conflicting range, calculate the first fluctuation amplitude of the vocal energy value and the second fluctuation amplitude of the scene energy value, compare the first fluctuation amplitude and the second fluctuation amplitude, the one with the larger fluctuation amplitude is the target fluctuation amplitude, determine the target part of speech from the vocal part of speech and the scene part of speech according to the target fluctuation amplitude, and determine the target energy value from the vocal energy value and the scene energy value.

[0053] For example, in the conflict interval, based on the principle of contrast, objects with stable fluctuations are often not suitable as the main object, because they may be affected by objects with large fluctuations in the relevant emotional expression. Therefore, in the conflict interval, if the human voice part of speech fluctuates greatly, the human voice part of speech is used as the target part of speech. If the scene part of speech fluctuates greatly, the scene part of speech is used as the target part of speech. The energy value corresponding to the target part of speech is the target energy value.

[0054] S104. If the vocal part of speech and the scene part of speech are in the same interval, compare the interval peak density of the vocal energy value and the interval peak density of the scene energy value. The one with the larger interval peak density is the target energy value. Determine the target part of speech from the vocal part of speech and the scene part of speech according to the target energy value.

[0055] For example, in non-different intervals, the greater the interval peak density, the greater the information density in the corresponding interval. In the absence of conflict, the greater the information density, the more it serves as the main object, thereby determining the target part of speech and target energy value.

[0056] S105. Determine a speech context score according to the target part of speech and the target energy value.

[0057] Exemplarily, this step requires calling a preset scoring rule and determining the speech context score according to the preset scoring rule and the target part of speech and target energy value.

[0058] S106 : Match the speech context score with a preset energy duty cycle table to obtain level change information.

[0059] For example, a preset energy duty cycle table can calculate brightness values based on the voice data and screen brightness of training data (classic videos), then convert them into corresponding duty cycles to determine the appropriate LED brightness setting for the current atmosphere. This data is created into an energy duty cycle table, and after obtaining the voice context score, it is matched to obtain level change information.

[0060] It should be noted that the level change information includes a high level interval and a low level interval. The voltage reference unit outputs a reference voltage V REF , the voltage reference unit stops outputting the reference voltage V in the low level interval REF, thereby indirectly controlling the duration of the high level output of the operational amplifier AMP, and further controlling the duty cycle of the low-voltage power tube MN1.

[0061] In some embodiments, the speech analysis model includes: a speech encoding layer, an attention layer, a multimodal projection layer and a decoding layer. The speech analysis model is used to perform context analysis on the target audio file to obtain context description information, including: S1021-S1026.

[0062] S1021. Perform time-frequency analysis and text alignment processing on the target audio file to generate a multimodal input matrix. The multimodal input matrix includes: a mel-spectrogram, a text part-of-speech tagging sequence, and a time alignment mapping matrix.

[0063] For example, the target audio file is resampled at a 16kHz sampling rate and framed using a Hamming window (25ms window length, 10ms step size). In frequency domain processing, a 128-dimensional Mel filter bank is used to extract the time-frequency spectrogram, and dynamic range compression (log(1+amplitude)) is used to enhance low-frequency features. Simultaneously, the audio is transcribed using a pre-trained speech recognition model to generate a timestamp-aligned text sequence. The cosine similarity between the morphemes of each speech frame and the corresponding text sequence is calculated. When the similarity falls below a threshold of 0.75, a secondary calibration is triggered, performing secondary time alignment. The output is a multimodal input matrix consisting of three submatrices: 1. A 64×128-dimensional Mel-frequency spectrogram; 2. A text part-of-speech tag sequence; and 3. A time alignment mapping matrix.

[0064] S1022. Based on the speech coding layer, perform hierarchical acoustic feature extraction on the multimodal input matrix to generate a human voice feature matrix, a scene feature matrix, and an interaction weight matrix.

[0065] The multimodal input matrix is fed into the speech encoding layer, which contains a dual-path CNN. In the vocal feature path, a five-layer depthwise separable convolutional network is used, each followed by an SE attention module, focusing on the vocal frequency band of 300-3000Hz. The scene feature path uses a dilated convolutional structure with a spectral masking layer to suppress the energy in the vocal frequency band, focusing on extracting low-frequency ambient sound features from 20-300Hz. An innovative cross-path feature gating mechanism is introduced: a sigmoid function is used to generate the feature suppression coefficient of the vocal path on the scene path, and the output is a feature cube consisting of a 64×32-dimensional vocal feature matrix, a 64×32-dimensional scene feature matrix, and a weight matrix for the interaction between the two. This design achieves feature decoupling between vocal and ambient sound. Experiments show that the purity of vocal features in noisy environments is improved by 42%.

[0066] S1023. Based on the attention layer, dynamically weight the human voice feature matrix, the scene feature matrix, and the interaction weight matrix to generate a context compression matrix.

[0067] In some embodiments, based on the attention layer, the human voice feature matrix, the scene feature matrix and the interaction weight matrix are dynamically weighted to generate a context compression matrix, including: S231-S234.

[0068] S231. Perform multi-head attention processing on the human voice feature matrix to generate a human voice attention feature matrix.

[0069] S232. Perform sparse attention processing on the scene feature matrix to generate a scene attention feature matrix.

[0070] S233. The human voice attention feature matrix is used as a position bias term and injected into the sparse attention processing process to generate a cross-modal interaction matrix.

[0071] S234. Perform feature fusion and compression on the human voice attention feature matrix, the scene attention feature matrix, and the cross-modal interaction matrix to generate a context compression matrix.

[0072] For example, a parallel dual-attention channel is constructed in the attention layer. The vocal channel uses a query vector learnable multi-head attention (8 heads), where the Q matrix is initialized by trainable parameters, and the K and V matrices are derived from the vocal feature matrix. The scene channel uses sparse attention based on energy thresholds, defining an energy weight coefficient α. When α < 0.6, the attention connection of the current frame is blocked. The innovation lies in the cross-feature modulation module: the output of the vocal attention is used as the position bias term of the scene channel, and cross-modal interaction is achieved based on the position bias term. After layer normalization, the output is obtained as a 32×64-dimensional context compression matrix, which contains intermediate representations such as the vocal energy distribution histogram and the scene feature activation heat map.

[0073] S1024. Based on the multimodal projection layer, the context compression matrix is mapped and optimized into feature space to generate a human voice energy vector, a scene category vector, and a cross-modal correlation matrix.

[0074] Exemplarily, the fully connected layer adopts a dual-stream projection structure design. In the voice projection stream, the 32×64-dimensional feature matrix is linearly transformed and reduced to 16×16, and the improved NT-Xent contrast loss is applied, where the positive samples come from cross-modal samples of the same speaker, and the negative samples contain scene feature interference items. The scene projection stream introduces an adversarial training mechanism, which makes the scene features difficult to distinguish from random noise vectors through the gradient reversal layer, thereby enhancing the robustness of the features. The key innovation lies in the construction of the cross-modal interaction matrix: the association matrix of voice energy value and scene part of speech is established, and by modeling the conditional probability distribution, the output includes: 1. 16-dimensional voice energy vector; 2. 16-dimensional scene category vector; 3. cross-modal association matrix.

[0075] S1025. Based on the decoding layer, dynamically fuse and decode the human voice energy vector, scene category vector, and cross-modal association matrix to generate a situation description information sequence.

[0076] In some embodiments, based on the decoding layer, the human voice energy vector, the scene category vector and the cross-modal association matrix are dynamically fused and decoded to generate a context description information sequence, including: S251-S254.

[0077] S251. Initialize the context state of the human voice energy vector and the scene category vector to generate a gating coefficient matrix.

[0078] Exemplarily, based on a conditional gated recurrent unit, at time step zero, the vocal energy vector and the scene category vector are dimensionally aligned, mapped to the latent space via linear transformation, and the initial hidden state is calculated. At time step 1 or greater, a gating coefficient matrix is generated based on the previous hidden state, the current vocal context vector (calculated by taking the dot product of the cross-modal association matrix and the previous hidden state), and the scene context vector (calculated by combining the scene category vector with the attention weights of the previous hidden state).

[0079] S252. Perform dual pointer network processing on the gating coefficient matrix and the cross-modal association matrix to generate the human voice part-of-speech selection probability and the scene word sampling probability.

[0080] For example, in the voice pointer network, the hidden state is concatenated with the current voice context vector, a linear transformation is performed to generate a part-of-speech score vector, and softmax normalization is performed to obtain the voice part-of-speech selection probability. In the scene pointer network, the hidden state is concatenated with the scene context vector, a linear transformation is performed to generate a scene word score vector, and dynamic scaling is performed based on the scene energy value to generate the scene word sampling probability.

[0081] S253. Perform energy-driven mixed distribution calculation on the human voice part-of-speech selection probability and the scene word sampling probability to generate an output word probability vector.

[0082] The mixing weight is calculated based on the vocal energy value and scene energy value at the current time step. The vocal part-of-speech selection probability and the scene word sampling probability are weighted and fused to generate a mixed probability distribution. Simultaneously, the mixed probability distribution is sparsely processed using the row-column constraints of the cross-modal association matrix to mask the part-of-speech combination probabilities that do not match the non-zero element positions in the cross-modal association matrix.

[0083] S254: Serialize and decode the output word probability vector and perform candidate pruning to generate a context description information sequence.

[0084] Exemplarily, a beam search algorithm is used to perform multi-step prediction on the mixed probability distribution, retaining candidate sequences at each step; for each candidate sequence, its cumulative log-likelihood score is calculated, and combined with the temporal smoothness constraint of the scene energy value to generate a context description score; when the length of the candidate sequence reaches a preset maximum value or a terminator is generated, the sequence with the highest context description score is selected as the context description information sequence, and a merge and deduplication operation is performed on consecutively repeated part-of-speech tags in the sequence.

[0085] S1026. Based on the decoding layer, perform multi-objective joint optimization and adaptive post-processing on the context description information sequence to generate context description data.

[0086] The context description information sequence is subjected to multi-objective joint optimization and adaptive post-processing to generate final structured context description data; this includes: constructing a joint optimization objective including context classification cross entropy loss, contrastive learning loss, mutual information minimization loss and decoding reconstruction loss, and dynamically allocating loss weights through an adaptive weight adjustment strategy; when it is detected that the human voice energy value of consecutive frames exceeds a preset threshold, triggering an energy redistribution algorithm to adjust the energy distribution, and outputting JSON format data containing timestamp-aligned human voice parts of speech, energy curves and scene labels.

[0087] An embodiment of the present application provides an electronic device, which includes the high-voltage linear LED driving circuit as described in any one of the embodiments of the present application.

[0088] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present application, and such modifications or substitutions should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A high-voltage linear LED drive circuit, characterized in that: The high-voltage linear LED driving circuit includes: a clamping diode D1, a current reference unit, a voltage reference unit, a voltage reference driving stage unit, an operational amplifier AMP, a low-voltage power tube MN1, a high-voltage power tube MN2, a protection diode D2 and a sampling resistor R1; The cathode of the clamping diode D1 is used to connect the external power supply V IN , the anode of the external LED, the cathode of the clamping diode D1 is also connected to the input end of the current reference unit, the voltage driving end of the operational amplifier AMP, the cathode of the protection diode D2, and the Gate end of the high-voltage power tube MN2 respectively; the anode of the clamping diode D1 is grounded; the output end of the current reference unit is connected to the bias current input end of the operational amplifier AMP; the output end of the voltage reference unit is connected to the input end of the voltage reference driving stage unit; the output end of the voltage reference driving stage unit is connected to the positive electrode of the operational amplifier AMP to provide a reference voltage V to the operational amplifier AMP REF The output end of the operational amplifier AMP is connected to the Gate end of the low-voltage power tube MN1; the Drain end of the low-voltage power tube MN1 is respectively connected to the anode of the protection diode D2 and the Source end of the high-voltage power tube MN2, and the Source end of the low-voltage power tube MN1 is grounded through the sampling resistor R1; the Drain end of the high-voltage power tube MN2 is used to be connected to the cathode of the external LED; Among them, the first threshold voltage V of the Gate terminal of the low-voltage power tube MN1 is th1 is less than the second threshold voltage V of the Gate terminal of the high-voltage power tube MN2 th2 The parasitic capacitance of the Gate terminal of the low-voltage power tube MN1 is smaller than the parasitic capacitance of the Gate terminal of the high-voltage power tube MN2. The operational amplifier AMP, the low-voltage power tube MN1, and the sampling resistor R1 form a constant current loop, which indirectly controls the conduction of the high-voltage power tube MN2. The voltage reference unit is used to determine the reference voltage V according to a preset target audio file. REF The reference voltage V is generated according to the level change information REF .

2. The high-voltage linear LED driving circuit according to claim 1, wherein: The current reference unit includes: a current source I1, a first current power tube MN3, a second current power tube MN4 and a second sampling resistor R3; The input end of the current source I1 is connected to the cathode of the clamping diode D1, and the output end of the current source I1 is respectively connected to the Gate end of the first current power tube MN3 and the Drain end of the second current power tube MN4; the Drain end of the first current power tube MN3 is connected to the positive electrode of the operational amplifier AMP, and the Source end of the first current power tube MN3 is respectively connected to the Gate end of the second current power tube MN4 and the first end of the second sampling resistor R3; the second end of the second sampling resistor R3 and the Source end of the second current power tube MN4 are both grounded.

3. The high-voltage linear LED driving circuit according to claim 2, wherein: The process angles of the low-voltage power tube MN1 , the first current power tube MN3 , and the second current power tube MN4 are all the same.

4. The high-voltage linear LED driving circuit according to claim 1, wherein: The high-voltage linear LED driving circuit further includes: a current limiting resistor R2 and a filter capacitor C1; The first ends of the current limiting resistors R2 are respectively used to connect to the external power supply V IN , the anode of the external LED, the second end of the current limiting resistor R2 is connected to the cathode of the clamping diode D1; the first end of the filter capacitor C1 is connected to the cathode of the clamping diode D1, and the second end of the filter capacitor C1 is grounded.

5. The high-voltage linear LED driving circuit according to claim 4, wherein: The voltage reference unit is used to determine the reference voltage V according to the preset target audio file. REF When the level change information is received, it is specifically used to execute: Get the target audio file; Performing context analysis on the target audio file using a preset speech analysis model to obtain context description information, the context description information including voice part of speech, voice energy value, scene part of speech, and scene energy value; If the vocal part of speech and the scene part of speech are in a conflicting interval, calculating a first fluctuation amplitude of the vocal energy value and a second fluctuation amplitude of the scene energy value, comparing the first fluctuation amplitude and the second fluctuation amplitude, the larger fluctuation amplitude is the target fluctuation amplitude, determining a target part of speech from the vocal part of speech and the scene part of speech according to the target fluctuation amplitude, and determining a target energy value from the vocal energy value and the scene energy value; If the vocal part of speech and the scene part of speech are in a non-differential interval, comparing the interval peak density of the vocal energy value and the interval peak density of the scene energy value, the interval peak density having the larger one being the target energy value, and determining the target part of speech from the vocal part of speech and the scene part of speech according to the target energy value; determining a speech context score according to the target part of speech and the target energy value; The voice context score is matched with a preset energy duty cycle table to obtain the level change information.

6. The high-voltage linear LED driving circuit according to claim 5, wherein: The speech analysis model includes: a speech encoding layer, an attention layer, a multimodal projection layer, and a decoding layer. The speech analysis model is used to perform context analysis on the target audio file to obtain context description information, including: Performing time-frequency analysis and text alignment processing on the target audio file to generate a multimodal input matrix, wherein the multimodal input matrix includes: a mel-spectrogram, a text part-of-speech tag sequence, and a time alignment mapping matrix; Based on the speech coding layer, performing hierarchical acoustic feature extraction on the multimodal input matrix to generate a human voice feature matrix, a scene feature matrix and an interaction weight matrix; Based on the attention layer, dynamically weighting the human voice feature matrix, the scene feature matrix, and the interaction weight matrix to generate a context compression matrix; Based on the multimodal projection layer, the context compression matrix is mapped and optimized into a feature space to generate a human voice energy vector, a scene category vector, and a cross-modal correlation matrix; Based on the decoding layer, dynamically fusing and decoding the human voice energy vector, the scene category vector, and the cross-modal association matrix to generate a context description information sequence; Based on the decoding layer, multi-objective joint optimization and adaptive post-processing are performed on the context description information sequence to generate context description data.

7. The high-voltage linear LED driving circuit according to claim 6, wherein: The method of dynamically weighting the human voice feature matrix, the scene feature matrix, and the interaction weight matrix based on the attention layer to generate a context compression matrix includes: Performing multi-head attention processing on the vocal feature matrix to generate a vocal attention feature matrix; Performing sparse attention processing on the scene feature matrix to generate a scene attention feature matrix; The human voice attention feature matrix is used as a position bias term and injected into the sparse attention processing process to generate a cross-modal interaction matrix; The human voice attention feature matrix, the scene attention feature matrix and the cross-modal interaction matrix are subjected to feature fusion and compression to generate a context compression matrix.

8. The high-voltage linear LED driving circuit according to claim 6, wherein: The step of dynamically fusing and decoding the human voice energy vector, the scene category vector, and the cross-modal association matrix based on the decoding layer to generate a context description information sequence includes: Initializing the context state of the human voice energy vector and the scene category vector to generate a gating coefficient matrix; Performing dual pointer network processing on the gating coefficient matrix and the cross-modal association matrix to generate human voice part-of-speech selection probability and scene word sampling probability; Performing energy-driven mixed distribution calculation on the human voice part-of-speech selection probability and the scene word sampling probability to generate an output word probability vector; The output word probability vector is serialized and decoded and candidate pruned to generate a context description information sequence.

9. An electronic device, characterized in that: The electronic device comprises the high-voltage linear LED driving circuit according to any one of claims 1 to 8.

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