Voltage converter, RGB driving chip and display screen lamp bead assembly

Abstract

The embodiment of the present application discloses a voltage converter, comprising a conversion control distribution processing module, a control output unit, an input voltage detection unit and a plurality of charge pump units, the plurality of charge pump units are connected in series, the output end of the last charge pump unit is connected with the control output unit, the input end of the first charge pump unit is connected with the voltage input end, the input end of the plurality of charge pump units is connected with the control output unit, the input voltage detection unit is connected with the voltage input end, the conversion control distribution processing module is connected with the input voltage detection unit, the control output unit and the plurality of charge pump units, so as to control the working of the control output unit and the plurality of charge pump units according to the input voltage collected by the input voltage detection unit, and the output end of the control output unit is the voltage output end of the voltage converter. The present application also discloses an RGB driving chip and a display screen lamp bead assembly.

Description

Technical Field

[0001] This invention relates to the field of LED display technology, and in particular to a voltage converter, an RGB driver chip, and a display LED assembly. Background Technology

[0002] Currently, most outdoor LED displays on the market use a common anode 5V power supply, employing common anode RGB three-in-one LED chips. This means that the red LED (R), green LED (G), and blue LED (B) all use a 5V power supply. However, the actual power supply voltage required for normal LED operation is 2-3.5V. Specifically, the power supply voltage for the red LED (R) is approximately 1.8-2.2V, and the power supply voltage for the green LED (G) and blue LED (B) is approximately 3.2-3.4V. LED displays using a common anode 5V power supply will have a significant amount of wasted power, resulting in low efficiency. Furthermore, when there is a significant amount of wasted power, it will be converted into heat, generating a large amount of heat. This can easily lead to a significant increase in the temperature of the constant current chip and the entire display cabinet, affecting the reliability and lifespan of the LED display product. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a voltage converter, an RGB driver chip and a display LED assembly to reduce useless power, improve the working efficiency of the LEDs and reduce heat generation.

[0004] In a first aspect, embodiments of the present invention provide a voltage converter, including a conversion control and distribution processing module, a control output unit, an input voltage detection unit, and multiple charge pump units. The multiple charge pump units are connected in series, with the output terminal of the last charge pump unit connected to the control output unit, the input terminal of the first charge pump unit connected to a voltage input terminal, and the input terminals of all the charge pump units connected to the control output unit. The input voltage detection unit is connected to the voltage input terminal. The conversion control and distribution processing module is connected to the input voltage detection unit, the control output unit, and the multiple charge pump units respectively, so as to control the operation of the control output unit and the multiple charge pump units according to the input voltage collected by the input voltage detection unit. The output terminal of the control output unit is the voltage output terminal of the voltage converter.

[0005] The further technical solution is as follows: there are three charge pump units, namely a first charge pump unit, a second charge pump unit and a third charge pump unit. The input terminal of the first charge pump unit is connected to the voltage input terminal. The first charge pump unit, the second charge pump unit and the third charge pump unit are connected in series in sequence. The input terminals of the first charge pump unit, the second charge pump unit and the third charge pump unit are all connected to the control output unit. The output terminal of the third charge pump unit is connected to the control output unit.

[0006] The further technical solution is as follows: The charge pump unit includes a first NMOS transistor, a second NMOS transistor, a third NMOS transistor, a fourth NMOS transistor, a fifth NMOS transistor, a sixth NMOS transistor, a seventh NMOS transistor, an eighth NMOS transistor, a ninth NMOS transistor, a tenth NMOS transistor, an eleventh NMOS transistor, a twelfth NMOS transistor, a first capacitor, and a second capacitor. The drains of the first NMOS transistor, the third NMOS transistor, the seventh NMOS transistor, and the ninth NMOS transistor are all connected to the input terminal. The sources of the first NMOS transistor and the third NMOS transistor are respectively connected to the two ends of the first capacitor. The drains of the second NMOS transistor and the fourth NMOS transistor are respectively connected to the sources of the first NMOS transistor and the third NMOS transistor. The sources of the seventh NMOS transistor and the ninth NMOS transistor are respectively connected to the two ends of the second capacitor. The drains of the eighth NMOS transistor and the tenth NMOS transistor are respectively connected to the sources of the seventh NMOS transistor and the ninth NMOS transistor. The second NMOS transistor, the third NMOS transistor, the fourth NMOS transistor, the fifth NMOS transistor, the sixth NMOS transistor, the seventh NMOS transistor, the eighth NMOS transistor, the ninth NMOS transistor, the eleventh NMOS transistor, the twelfth NMOS transistor, the first capacitor, and the second capacitor. The sources of the fourth NMOS transistor, the eighth NMOS transistor, and the tenth NMOS transistor are all connected to the drain of the twelfth NMOS transistor. The source of the twelfth NMOS transistor is connected to the output terminal. A grounding capacitor is connected between the output terminal and the source of the twelfth NMOS transistor. The drain of the fifth NMOS transistor is connected to the source of the third NMOS transistor and the drain of the sixth NMOS transistor. The source of the sixth NMOS transistor is connected to the drain of the eighth NMOS transistor. The sources of the fifth NMOS transistor and the eleventh NMOS transistor are both grounded. The drain of the eleventh NMOS transistor is connected to the source of the ninth NMOS transistor. The gates of the first NMOS transistor, the second NMOS transistor, the third NMOS transistor, the fourth NMOS transistor, the fifth NMOS transistor, the sixth NMOS transistor, the seventh NMOS transistor, the eighth NMOS transistor, the ninth NMOS transistor, the tenth NMOS transistor, the eleventh NMOS transistor, and the twelfth NMOS transistor are all connected to the conversion control and distribution processing module.

[0007] A further technical solution is as follows: the voltage converter further includes an output voltage detection unit, which is connected to the output terminal of the control output unit and the conversion control distribution processing module respectively, so as to collect and transmit the output voltage of the control output unit to the conversion control distribution processing module.

[0008] Secondly, embodiments of the present invention provide an RGB driver chip, including two voltage converters as described above, an RGB data processing module, and three constant current driving modules. The output terminals of the three constant current driving modules are respectively connected to the anodes of red, green, and blue LEDs. One of the voltage converters is connected to the red LED through one of the constant current driving modules, and the remaining two constant current driving modules are each connected to another voltage converter and respectively connected to the green and blue LEDs. The RGB data processing module is connected to a signal input terminal, a signal output terminal, the three constant current driving modules, and the voltage input terminal.

[0009] Thirdly, embodiments of the present invention provide an RGB driver chip, including three voltage converters as described above, an RGB data processing module, and three constant current driving modules. The output terminals of the three constant current driving modules are respectively connected to the anodes of red LEDs, green LEDs, and blue LEDs. The voltage converters correspond one-to-one with the constant current driving modules and are electrically connected to each other. The RGB data processing module is respectively connected to a signal input terminal, a signal output terminal, the three constant current driving modules, and the voltage input terminal.

[0010] A further technical solution is as follows: the RGB driver chip also includes a voltage converter that is connected to the voltage input terminal and the RGB data processing module respectively.

[0011] The further technical solution is as follows: the constant current drive module includes a constant current control unit and a PWM control unit. The constant current control unit includes a constant current control transistor and an operational amplifier. The source of the constant current control transistor is connected to the voltage output terminal of the voltage converter. The gate of the constant current control transistor is connected to the output terminal of the operational amplifier. The non-inverting input terminal of the operational amplifier is connected to a reference standard voltage. The inverting input terminal of the operational amplifier is connected to the drain of the constant current control transistor through a constant current resistor. The input terminal of the PWM control unit is electrically connected between the constant current resistor and the inverting input terminal of the operational amplifier. The PWM control unit is connected to the RGB data processing module.

[0012] The further technical solution is as follows: the PWM control unit includes a PWM control transistor, the source of the PWM control transistor is the input terminal of the PWM control unit, the source of the PWM control transistor is electrically connected between the constant current resistor and the inverting input terminal of the operational amplifier, the gate of the PWM control transistor is connected to the RGB data processing module, and the drain of the PWM control transistor is the output terminal of the constant current driving module.

[0013] Fourthly, embodiments of the present invention provide a display screen LED assembly, including an RGB LED group and the aforementioned RGB driver chip. The RGB LED group is electrically connected to the RGB driver chip. The RGB LED group includes red LEDs, green LEDs, and blue LEDs. The red LEDs, green LEDs, and blue LEDs are connected to a common cathode. The anodes of the red LEDs, green LEDs, and blue LEDs are respectively connected to the output terminals of the corresponding constant current driving modules.

[0014] The beneficial technical effects of this invention are as follows: The voltage converter of this invention, by setting up a conversion control and distribution processing module, a control output unit, an input voltage detection unit, and multiple charge pump units, enables the conversion control and distribution processing module to control the working mode of each charge pump unit according to the input voltage collected by the input voltage detection unit, thereby converting the input voltage into the required output voltage, and outputting the corresponding output voltage through the control output unit, so that the output voltage is close to the voltage required by the LED, thereby reducing useless power, improving conversion efficiency, improving LED working efficiency, reducing heat generation, avoiding the problem of accelerated LED aging due to high temperature, and extending the life of the LED. Furthermore, the output terminal of the voltage converter is connected to the anode of the LED, so that the LED can be connected to a common cathode, which can prevent the display color deviation problem caused by the unstable output voltage when the LED is connected to a common anode. Moreover, the voltage conversion through the charge pump unit realizes automatic voltage regulation output for wide voltage input, simplifies the circuit structure, and facilitates miniaturization and small size. Meanwhile, the RGB driver chip and display LED assembly of the present invention also have the above-mentioned functions. Moreover, the RGB driver chip generates the current required for the LED to work more accurately by setting a constant current drive module connected to the voltage converter. The RGB driver chip also sets an RGB data processing module to obtain the corresponding PWM duty cycle according to the data to be displayed and adjusts and controls the brightness of the LED through the constant current drive module. The output terminal of the constant current drive module is connected to the anode of the LED. The LEDs of the RGB LED group are connected to a common cathode, which can effectively reduce the voltage drop on the constant current drive module. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a block diagram of the architecture of a voltage converter provided in an embodiment of the present invention;

[0017] Figure 2 A circuit diagram of a charge pump unit provided in an embodiment of the present invention;

[0018] Figure 3 A circuit diagram of a display screen LED assembly provided in an embodiment of the present invention;

[0019] Figure 4 A circuit diagram of a display screen LED assembly is provided for another embodiment of the present invention. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0022] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. 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.

[0023] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0024] Please see Figure 1 , Figure 1This is a block diagram of a voltage converter architecture provided in an embodiment of the present invention. The voltage converter 10 includes a conversion control and distribution processing module 11, a control output unit 12, an input voltage detection unit 13, and multiple charge pump units 14. The multiple charge pump units 14 are connected in series. The output terminal of the last charge pump unit 14 is connected to the control output unit 12, and the input terminal of the first charge pump unit 14 is connected to the voltage input terminal VIN. The input terminals of the multiple charge pump units 14 are all connected to the control output unit 12. The input voltage detection unit 13 is connected to the voltage input terminal VIN. The conversion control and distribution processing module 11 is connected to the input voltage detection unit 13, the control output unit 12, and the multiple charge pump units 14 respectively, so as to control the operation of the control output unit 12 and the multiple charge pump units 14 according to the input voltage collected by the input voltage detection unit 13. The output terminal of the control output unit 12 is the voltage output terminal VOUT of the voltage converter 10.

[0025] The voltage input terminal VIN can be connected to the power supply VDD, so that the input terminals of the input voltage detection unit 13 and the first charge pump unit 14 are both connected to the power supply VDD. The input voltage collected by the input voltage detection unit 13 is the voltage of the power supply VDD. Collecting the input voltage through the input voltage detection unit 13 facilitates the subsequent conversion control and distribution processing module 11 to control each charge pump unit 14 to operate for voltage conversion. Finally, the output unit 12 outputs a voltage close to the voltage required by the corresponding LED. The conversion control and distribution processing module 11 analyzes and calculates the collected input voltage to obtain the conversion coefficient of the charge pump unit 14 that needs to perform output conversion and controls the corresponding charge pump unit 14 to operate, thereby obtaining the optimal output combination for the required output voltage. The conversion coefficient of the charge pump unit 14 can be 0.33, 0.5, 0.66, 1.5, and 2.0. Different charge pump units 14 are connected in series, and the input terminal of each charge pump unit 14 is connected to the control output unit 12. The required output voltage can be obtained and output through multi-stage connection and conversion coefficient. This makes the output voltage obtained by conversion more accurate and can convert more input voltages into the required output voltage, thus expanding the application range. The voltage converter 10 is configured with a conversion control and distribution processing module 11, a control output unit 12, an input voltage detection unit 13, and multiple charge pump units 14. The conversion control and distribution processing module 11 controls the operating mode of each charge pump unit 14 based on the input voltage collected by the input voltage detection unit 13, thereby converting the input voltage into the required output voltage. The corresponding output voltage is then output through the control output unit 12, ensuring the output voltage is close to the voltage required by the LED, reducing useless power, improving conversion efficiency, increasing LED operating efficiency, reducing heat generation, avoiding accelerated LED aging due to high temperatures, and extending LED lifespan. Furthermore, the output terminal of the voltage converter 10 is connected to the anode of the LED, allowing for common cathode connection of subsequent LEDs. This prevents color deviation caused by unstable output voltage when LEDs are connected to a common anode. The voltage conversion via the charge pump units 14 enables automatic voltage regulation for wide input voltages, simplifying the circuit structure and facilitating miniaturization and small size.

[0026] Specifically, in this embodiment, there are three charge pump units 14, namely a first charge pump unit 141, a second charge pump unit 142, and a third charge pump unit 143. The input terminal of the first charge pump unit 141 is connected to the voltage input terminal VIN. The first charge pump unit 141, the second charge pump unit 142, and the third charge pump unit 143 are connected in series. The output terminal of the first charge pump unit 141 is connected to the input terminal of the second charge pump unit 142, and the output terminal of the second charge pump unit 142 is connected to the input terminal of the third charge pump unit 143. The input terminals of the first charge pump unit 141, the second charge pump unit 142, and the third charge pump unit 143 are all connected to the control output unit 12, and the output terminal of the third charge pump unit 143 is connected to the control output unit 12.

[0027] Specifically, the voltage converter 10 further includes an output voltage detection unit 15, which is connected to both the output terminal of the control output unit 12 and the conversion control distribution processing module 11 to acquire and transmit the output voltage of the control output unit 12 to the conversion control distribution processing module 11. The conversion control distribution processing module 11 acquires the output voltage, analyzes and calculates it, obtains the conversion coefficient of the charge pump unit 14 that needs to perform output conversion, and controls the corresponding charge pump unit 14 to obtain the optimal output combination for the required output voltage.

[0028] The required output voltage for the LED refers to the output voltage required by the voltage converter 10. The corresponding value of the required output voltage can be the sum of the LED's supply voltage and the minimum voltage drop (0.3V) for constant current control. Therefore, the required output voltage for the red LED is 2.3V, while the required output voltages for the green and blue LEDs are both 3.5V. When the input voltage is 5V, the input voltage detection unit 13 transmits the collected input voltage to the conversion control and distribution processing module 11 for analysis and calculation. For the red LED requiring an output voltage of 2.3V, the optimal mode for the corresponding voltage converter 10 is as follows: the conversion control and distribution processing module 11 controls the conversion coefficient of the first charge pump unit 141 to 0.5 and controls the second charge pump unit 142 and the third charge pump unit 143 to be turned off. That is, the first charge pump unit 141 is in 0.5X step-down mode. At this time, an output voltage of 2.5V is obtained, and the light conversion efficiency reaches 80%. The light conversion efficiency is obtained by calculating the percentage ratio of the LED's supply voltage to the actual output voltage of the voltage converter 10. For the green and blue LEDs, which require an output voltage of 3.5V, the optimal configuration of the voltage converter 10 is as follows: the conversion control and distribution processing module 11 controls the conversion coefficient of the first charge pump unit 141 to 0.5 and the conversion coefficient of the second charge pump unit 142 to 1.5, while controlling the third charge pump unit 143 to be turned off. That is, the first charge pump unit 141 is in 0.5X buck mode and the second charge pump unit 142 is in 1.5X boost mode. At this time, an output voltage of 3.75V is obtained, and the light conversion efficiency reaches 85.33%.

[0029] When the input voltage is 10V, the input voltage detection unit 13 transmits the collected input voltage to the conversion control and distribution processing module 11 for analysis and calculation. For the output voltage of 2.3V required by the red LED, the optimal mode of the corresponding voltage converter 10 is as follows: the conversion control and distribution processing module 11 controls the conversion coefficient of the first charge pump unit 141 and the second charge pump unit 142 to be 0.5 and controls the third charge pump unit 143 to be turned off. That is, the first charge pump unit 141 and the second charge pump unit 142 are both in 0.5X step-down mode. At this time, an output voltage of 2.5V is obtained, and the light conversion efficiency reaches 80%. For the green and blue LED chips, which require an output voltage of 3.5V, the optimal configuration for the corresponding voltage converter 10 is as follows: the conversion control and distribution processing module 11 controls the conversion coefficients of the first charge pump unit 141 and the second charge pump unit 142 to be both 0.5, and controls the conversion coefficient of the third charge pump unit 143 to be 1.5. That is, the first charge pump unit 141 and the second charge pump unit 142 are both in 0.5X buck mode, while the third charge pump unit 143 is in 1.5X boost mode. At this time, an output voltage of 3.75V is obtained, and the light conversion efficiency reaches 85.33%.

[0030] CombinationFigure 2Specifically, the charge pump unit 14 includes a first NMOS transistor S1, a second NMOS transistor S2, a third NMOS transistor S3, a fourth NMOS transistor S4, a fifth NMOS transistor S5, a sixth NMOS transistor S6, a seventh NMOS transistor S7, an eighth NMOS transistor S8, a ninth NMOS transistor S9, a tenth NMOS transistor S10, an eleventh NMOS transistor S11, a twelfth NMOS transistor S12, a first capacitor CF1, and a second capacitor CF2. The drains of the first NMOS transistor S1, the third NMOS transistor S3, the seventh NMOS transistor S7, and the ninth NMOS transistor S9 are all connected to the input terminal Vin. The sources of the first NMOS transistor S1 and the third NMOS transistor S3 are respectively connected to the input terminal Vin. The two ends of the first capacitor CF1 are connected. The drains of the second NMOS transistor S2 and the fourth NMOS transistor S4 are respectively connected to the sources of the first NMOS transistor S1 and the third NMOS transistor S3, such that the drains of the second NMOS transistor S2 and the fourth NMOS transistor S4 are respectively connected to the two ends of the first capacitor CF1. The sources of the seventh NMOS transistor S7 and the ninth NMOS transistor S9 are respectively connected to the two ends of the second capacitor CF2. The drains of the eighth NMOS transistor S8 and the tenth NMOS transistor S10 are respectively connected to the sources of the seventh NMOS transistor S7 and the ninth NMOS transistor S9, such that the drains of the eighth NMOS transistor S8 and the tenth NMOS transistor S10 are respectively connected to the sources of the seventh NMOS transistor S7 and the ninth NMOS transistor S9, such that the drains of the eighth NMOS transistor S8 and the tenth NMOS transistor S10 are respectively connected to the sources of the third NMOS transistor S3. The second NMOS transistor S2, the fourth NMOS transistor S4, the eighth NMOS transistor S8, and the tenth NMOS transistor S10 are all connected to the drain of the twelfth NMOS transistor S12. The source of the twelfth NMOS transistor S12 is connected to the output terminal Vout. A grounding capacitor CO is connected between the output terminal Vout and the source of the twelfth NMOS transistor S12. The drain of the fifth NMOS transistor S5 is connected to the source of the third NMOS transistor S3 and the drain of the sixth NMOS transistor S6. The source of the sixth NMOS transistor S6 is connected to the drain of the eighth NMOS transistor S8. The fifth NMOS transistor S5 and the tenth NMOS transistor S10 are connected to the drain of the twelfth NMOS transistor S12. The sources of all eleven NMOS transistors S11 are grounded, and the drain of the eleventh NMOS transistor S11 is connected to the source of the ninth NMOS transistor S9. The gates of the first NMOS transistor S1, the second NMOS transistor S2, the third NMOS transistor S3, the fourth NMOS transistor S4, the fifth NMOS transistor S5, the sixth NMOS transistor S6, the seventh NMOS transistor S7, the eighth NMOS transistor S8, the ninth NMOS transistor S9, the tenth NMOS transistor S10, the eleventh NMOS transistor S11, and the twelfth NMOS transistor S12 are all connected to the conversion control and distribution processing module 11, so that the switching on and off of each NMOS transistor can be controlled by the conversion control and distribution processing module 11.This adjusts the charge transfer in each capacitor to regulate the output voltage of the charge pump unit 14.

[0031] Please see Figure 3 , Figure 3 This is a circuit diagram of a display screen LED assembly provided in an embodiment of the present invention. The display screen LED assembly includes an RGB LED group 31 and an RGB driver chip 20. The RGB LED group 31 is electrically connected to the RGB driver chip 20. The RGB LED group 31 includes a red LED (LED-R), a green LED (LED-G), and a blue LED (LED-B). The red LED (LED-R), green LED (LED-G), and blue LED (LED-B) are connected to a common cathode. The anodes of the red LED (LED-R), green LED (LED-G), and blue LED (LED-B) are respectively connected to the output terminals of the corresponding constant current driving modules 22. Figure 3 As shown, the RGB driver chip 20 includes three voltage converters 10, an RGB data processing module 21, and three constant current driving modules 22. The output terminals of the three constant current driving modules 22 are respectively connected to the anodes of the red LED-R, green LED-G, and blue LED-B. The voltage converters 10 and the constant current driving modules 22 are in one-to-one correspondence and electrically connected to each other. The RGB data processing module 21 is connected to the signal input terminal DI, the signal output terminal DO, the three constant current driving modules 22, and the voltage input terminal VIN.

[0032] The cathodes of the red LED-R, green LED-G, and blue LED-B are all grounded. Three voltage converters 10 are used to convert the output voltage corresponding to the different colored LEDs, allowing for better control of the LEDs of different colors. The RGB driver chip 20 uses different voltage converters 10 and constant current drive modules 22 connected to the corresponding voltage converters 10 to control the operation of the corresponding LEDs according to their required output voltage. The voltage converters 10 include a conversion control distribution processing module 11, a control output unit 12, an input voltage detection unit 13, and multiple charge pump units 14. The conversion control distribution processing module 11 can control the operating mode of each charge pump unit 14 based on the input voltage collected by the input voltage detection unit 13, thereby converting the input voltage into the required output voltage and outputting it through the control output unit 12. The corresponding output voltage ensures that the output voltage is close to the voltage required by the LED, thereby reducing useless power, improving conversion efficiency, increasing LED working efficiency, reducing heat generation, avoiding accelerated LED aging due to high temperature, and extending LED lifespan. Furthermore, the output terminal of the voltage converter 10 is connected to the anode of the corresponding LED via the constant current drive module 22, enabling all LEDs to share a common cathode connection. This effectively prevents color deviation caused by unstable output voltage when LEDs are connected to a common anode. The voltage conversion via the charge pump unit 14 enables automatic voltage regulation for wide input voltages, simplifying the circuit structure and facilitating miniaturization and small size. Moreover, the RGB driver chip 20, through the constant current drive module 22 connected to the voltage converter 10, more accurately generates the current required for LED operation to drive and control the LEDs. The RGB driver chip 20 also uses an RGB data processing module 21 to convert and obtain the corresponding PWM duty cycle based on the data to be displayed, and adjusts and controls the LED brightness through the constant current drive module 22. Meanwhile, the display LED assembly 30 also has the above-mentioned functions. Moreover, the output terminal of the constant current drive module 22 is connected to the anode of the LED, and the LEDs of the RGB LED group 31 are connected to a common cathode, which can effectively reduce the voltage drop on the constant current drive module 22.

[0033] Specifically, in this embodiment, the RGB driver chip 20 further includes a voltage converter 10 connected to both the voltage input terminal VIN and the RGB data processing module 21. By configuring the voltage converter 10 connected to the RGB data processing module 21, the voltage can be controlled more precisely according to the voltage required by the RGB data processing module 21, thereby improving the working efficiency of the RGB data processing module 21.

[0034] Specifically, the constant current drive module 22 includes a constant current control unit 221 and a PWM control unit 222. The constant current control unit 221 includes a constant current control transistor and an operational amplifier. The source of the constant current control transistor is connected to the voltage output terminal of the voltage converter 10, and the gate of the constant current control transistor is connected to the output terminal of the operational amplifier. The non-inverting input terminal of the operational amplifier is connected to a reference standard voltage Vref, and the inverting input terminal of the operational amplifier is connected to the drain of the constant current control transistor via a constant current resistor. The input terminal of the PWM control unit 222 is electrically connected between the constant current resistor and the inverting input terminal of the operational amplifier. The PWM control unit 222 is connected to the RGB data processing module 21. By setting the constant current control unit 221, the rated current required by the LED bead is generated more accurately to drive and control the LED bead. By setting the PWM control unit 222 connected to the RGB data processing module 21, the PWM duty cycle of the LED bead calculated by the RGB data module 21 based on the data to be displayed is generated according to the driving of the RGB data module 21, and output to the corresponding LED bead to control the brightness of the LED bead.

[0035] Specifically, the PWM control unit 222 includes a PWM control transistor. The source of the PWM control transistor is the input terminal of the PWM control unit 222. The source of the PWM control transistor is electrically connected between the constant current resistor and the inverting input terminal of the operational amplifier. The gate of the PWM control transistor is connected to the RGB data processing module 21. The drain of the PWM control transistor is the output terminal of the constant current driving module 22, which is connected to the anode of the corresponding LED.

[0036] In this configuration, both the constant current control transistor and the PWM control transistor can be PMOS transistors. The constant current control transistor, operational amplifier, and constant current resistor of the constant current control unit 221 of the constant current drive module 22 connected to the red LED-R are denoted as QR, AR, and R1, respectively; the constant current control transistor, operational amplifier, and constant current resistor of the constant current control unit 221 of the constant current drive module 22 connected to the green LED-G are denoted as QG, AG, and R2, respectively; and the constant current control transistor, operational amplifier, and constant current resistor of the constant current control unit 221 of the constant current drive module 22 connected to the blue LED-B are denoted as QB, AB, and R3, respectively. The PWM control transistor of the PWM control unit 222 of the constant current drive module 22 connected to the red LED-R is denoted as PR; the PWM control transistor of the PWM control unit 222 of the constant current drive module 22 connected to the green LED-G is denoted as PG; and the PWM control transistor of the PWM control unit 222 of the constant current drive module 22 connected to the blue LED-B is denoted as PB.

[0037] Please seeFigure 4 , Figure 4 The circuit diagram provided in another embodiment of the present invention is a display screen LED assembly. The display screen LED assembly includes an RGB LED group 31 and an RGB driver chip 20. The RGB LED group 31 is electrically connected to the RGB driver chip 20. The RGB LED group 31 includes a red LED (LED-R), a green LED (LED-G), and a blue LED (LED-B). The red LED (LED-R), the green LED (LED-G), and the blue LED (LED-B) are connected to a common cathode. The anodes of the red LED (LED-R), the green LED (LED-G), and the blue LED (LED-B) are respectively connected to the output terminals of the corresponding constant current driving modules 22. Figure 4 As shown, in this embodiment, the RGB driver chip 31 includes two voltage converters 10, an RGB data processing module 21, and three constant current driving modules 22. The output terminals of the three constant current driving modules 22 are respectively connected to the anodes of the red LED-R, green LED-G, and blue LED-B. One voltage converter 10 is connected to the red LED-R through one constant current driving module 22, and the remaining two constant current driving modules 22 are each connected to the other voltage converter 10 and respectively connected to the green LED-G and blue LED-B. The RGB data processing module 21 is connected to the signal input terminal DI, the signal output terminal DO, the three constant current driving modules 22, and the voltage input terminal VIN. The remaining structure and functions are similar to those in the previous embodiment and will not be described again here.

[0038] In summary, the voltage converter of the present invention, by setting up a conversion control and distribution processing module, a control output unit, an input voltage detection unit, and multiple charge pump units, enables the conversion control and distribution processing module to control the working mode of each charge pump unit according to the input voltage collected by the input voltage detection unit, thereby converting the input voltage into the required output voltage. The output unit then outputs the corresponding output voltage, ensuring that the output voltage is close to the voltage required by the LED, thus reducing useless power, improving conversion efficiency, increasing LED working efficiency, reducing heat generation, avoiding accelerated LED aging due to high temperatures, and extending LED lifespan. Furthermore, the output terminal of the voltage converter is connected to the anode of the LED, allowing subsequent LEDs to be connected with a common cathode, preventing color deviation caused by unstable output voltage when LEDs are connected with a common anode. Moreover, voltage conversion via the charge pump units enables automatic voltage regulation output for wide input voltages, simplifying the circuit structure and facilitating miniaturization and small size. Meanwhile, the RGB driver chip and display LED assembly of the present invention also have the above-mentioned functions. Moreover, the RGB driver chip generates the current required for the LED to work more accurately by setting a constant current drive module connected to the voltage converter. The RGB driver chip also sets an RGB data processing module to obtain the corresponding PWM duty cycle according to the data to be displayed and adjusts and controls the brightness of the LED through the constant current drive module. The output terminal of the constant current drive module is connected to the anode of the LED. The LEDs of the RGB LED group are connected to a common cathode, which can effectively reduce the voltage drop on the constant current drive module.

[0039] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention 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 invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A voltage converter, characterized in that, The system includes a conversion control and distribution processing module, a control output unit, an input voltage detection unit, and multiple charge pump units. The charge pump units are connected in series. The output of the last charge pump unit is connected to the control output unit, and the input of the first charge pump unit is connected to a voltage input terminal. The inputs of all the charge pump units are connected to the control output unit. The input voltage detection unit is connected to the voltage input terminal. The conversion control and distribution processing module is connected to the input voltage detection unit, the control output unit, and the multiple charge pump units to control the operation of the control output unit and the multiple charge pump units based on the input voltage acquired by the input voltage detection unit. The output of the control output unit is connected to the voltage input terminal. The voltage output terminal of the voltage converter has conversion coefficients of 0.33, 0.5, 0.66, 1.5, and 2.0 for the charge pump unit. The voltage converter also includes an output voltage detection unit, which is connected to the output terminal of the control output unit and the conversion control distribution processing module to collect and transmit the output voltage of the control output unit to the conversion control distribution processing module. The step of controlling the operation of the control output unit and the multiple charge pump units based on the input voltage collected by the input voltage detection unit is as follows: the conversion control distribution processing module analyzes and calculates the collected input voltage to obtain the conversion coefficients of the charge pump units that need to perform output conversion and controls the corresponding charge pump units to operate.

2. The voltage converter according to claim 1, characterized in that, The number of charge pump units is three, namely a first charge pump unit, a second charge pump unit, and a third charge pump unit. The input terminal of the first charge pump unit is connected to the voltage input terminal. The first charge pump unit, the second charge pump unit, and the third charge pump unit are connected in series in sequence. The input terminals of the first charge pump unit, the second charge pump unit, and the third charge pump unit are all connected to the control output unit. The output terminal of the third charge pump unit is connected to the control output unit.

3. The voltage converter according to claim 1, characterized in that, The charge pump unit includes a first NMOS transistor, a second NMOS transistor, a third NMOS transistor, a fourth NMOS transistor, a fifth NMOS transistor, a sixth NMOS transistor, a seventh NMOS transistor, an eighth NMOS transistor, a ninth NMOS transistor, a tenth NMOS transistor, an eleventh NMOS transistor, a twelfth NMOS transistor, a first capacitor, and a second capacitor. The drains of the first, third, seventh, and ninth NMOS transistors are all connected to the input terminal. The sources of the first and third NMOS transistors are respectively connected to the two ends of the first capacitor. The drains of the second and fourth NMOS transistors are respectively connected to the sources of the first and third NMOS transistors. The sources of the seventh and ninth NMOS transistors are respectively connected to the two ends of the second capacitor. The drains of the eighth and tenth NMOS transistors are respectively connected to the sources of the seventh and ninth NMOS transistors. The second NMOS transistor, the fourth NMOS transistor... The sources of the first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh, and twelfth NMOS transistors are all connected to the drain of the twelfth NMOS transistor. The source of the twelfth NMOS transistor is connected to the output terminal. A grounding capacitor is connected between the output terminal and the source of the twelfth NMOS transistor. The drain of the fifth NMOS transistor is connected to the source of the third and sixth NMOS transistors. The source of the sixth NMOS transistor is connected to the drain of the eighth NMOS transistor. The sources of the fifth and eleventh NMOS transistors are both grounded. The drain of the eleventh NMOS transistor is connected to the source of the ninth NMOS transistor. The gates of the first, second, third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, eleventh, and twelfth NMOS transistors are all connected to the conversion control and distribution processing module.

4. An RGB driver chip, characterized in that, The device includes two voltage converters as described in any one of claims 1 to 3, an RGB data processing module, and three constant current driving modules. The output terminals of the three constant current driving modules are respectively connected to the anodes of a red LED, a green LED, and a blue LED. One of the voltage converters is connected to the red LED through one of the constant current driving modules. The remaining two constant current driving modules are each connected to the other voltage converter and are respectively connected to the green LED and the blue LED. The RGB data processing module is connected to a signal input terminal, a signal output terminal, the three constant current driving modules, and the voltage input terminal.

5. An RGB driver chip, characterized in that, The device includes three voltage converters as described in any one of claims 1 to 3, an RGB data processing module, and three constant current driving modules. The output terminals of the three constant current driving modules are respectively connected to the anodes of red, green, and blue LED beads. The voltage converters correspond one-to-one with the constant current driving modules and are electrically connected to each other. The RGB data processing module is respectively connected to a signal input terminal, a signal output terminal, the three constant current driving modules, and the voltage input terminal.

6. The RGB driver chip according to claim 4 or 5, characterized in that, The RGB driver chip also includes a voltage converter that is connected to the voltage input terminal and the RGB data processing module respectively.

7. The RGB driver chip according to claim 4 or 5, characterized in that, The constant current drive module includes a constant current control unit and a PWM control unit. The constant current control unit includes a constant current control transistor and an operational amplifier. The source of the constant current control transistor is connected to the voltage output terminal of the voltage converter, and the gate of the constant current control transistor is connected to the output terminal of the operational amplifier. The non-inverting input terminal of the operational amplifier is connected to a reference standard voltage, and the inverting input terminal of the operational amplifier is connected to the drain of the constant current control transistor via a constant current resistor. The input terminal of the PWM control unit is electrically connected between the constant current resistor and the inverting input terminal of the operational amplifier. The PWM control unit is connected to the RGB data processing module.

8. The RGB driver chip according to claim 7, characterized in that, The PWM control unit includes a PWM control transistor. The source of the PWM control transistor is the input terminal of the PWM control unit. The source of the PWM control transistor is electrically connected between the constant current resistor and the inverting input terminal of the operational amplifier. The gate of the PWM control transistor is connected to the RGB data processing module. The drain of the PWM control transistor is the output terminal of the constant current driving module.

9. A display screen LED assembly, characterized in that, The device includes an RGB LED bead group and an RGB driver chip as described in any one of claims 4 to 8. The RGB LED bead group is electrically connected to the RGB driver chip. The RGB LED bead group includes red LED beads, green LED beads, and blue LED beads. The red LED beads, green LED beads, and blue LED beads are connected to a common cathode. The anodes of the red LED beads, green LED beads, and blue LED beads are respectively connected to the output terminals of the corresponding constant current driving modules.

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