Slope configurable wide range input LED drive control circuit and method

Abstract

The present invention relates to a slope-configurable wide-range input LED drive control circuit and method. The circuit comprises a plurality of LED drive control modules, wherein the LED drive control module comprises a slope-controllable drive module and a switch signal transmission module, wherein a switch control signal reference slope is configured in the slope-controllable drive module; the slope-controllable drive module uses the configured switch control signal reference slope to configure the rising section slope of the high-voltage switch control signal HV_PWM_IN and / or the falling section slope of the high-voltage switch control signal HV_PWM_IN, so as to generate a switch tube drive control signal DRV_G for driving and controlling the switch state of the corresponding power switch tube after the required slope configuration is performed based on the switch control signal reference slope. The present invention can realize LED drive control with a wide range input, improve EMI characteristics, and increase the response speed and reliability of the drive control.

Description

Technical Field

[0001] The invention relates to a driving control circuit and method, in particular to a slope-configurable wide-range input LED driving control circuit and method. Background Art

[0002] In recent years, LED light strings have been increasingly used in automobiles and new consumer electronics. Many applications require single-point PWM operation control of LED lights on an LED matrix. Therefore, the control of LEDs in practical applications is becoming more and more complex.

[0003] At present, common LED light strings and dot matrixes can be connected in series or in parallel. When there are a large number of LED lights, if the LED parallel connection method is used, the current of all LED lights will be very large, which will not only increase the voltage drop on the wire, but also make the anti-electromagnetic interference characteristics worse. When the series cascade method is used, the current on the bus can be made equal to the current of a single LED lamp, the voltage drop on the wire will be significantly reduced, and the EMI characteristics will be significantly improved. Therefore, the series LED light cascade method is becoming more and more common in LED light string and matrix light applications.

[0004] In order to achieve PWM dimming, flashing light effects and other effects on LED light strings, each LED needs to be independently controlled. In order to control each LED light independently, an LED switch control module is needed to achieve independent control of the LED lights. Figure 1 This is an existing typical LED switch control circuit.

[0005] Figure 1 In the circuit, the charge pump module (Charge pump) increases the VBAT voltage to a higher voltage to drive the switch tube M10 to be fully turned on or off. When the switch control signal OFF is 1, the lower lock switch 0 is closed. At the same time, the switch control signal ON is 0, and the upper lock switch 0 is disconnected. At this time, the node GA is pulled to a high potential, the NMOS tube M20 is turned on, the node GB is pulled down to a low potential, the switch tube M1 is turned off, and the current on LED_P flows through LED10, and LED10 is in the light-on state.

[0006] When the switch control signal OFF is 0, the lower locking switch 0 is disconnected. At the same time, the switch control signal ON is 1, and the upper locking switch 0 is closed. At this time, the node GA is pulled to a low potential, the NMOS tube M20 is disconnected, the node GB is pulled up to a high potential, the switch tube M10 is turned on, the current on LED_P flows through the switch tube M10, LED10 is bypassed, and LED10 is in the off state.

[0007] Above Figure 1The LED switch control circuit has the following disadvantages in the current LED driver chip application:

[0008] 1) The power supply of the driving end is VBAT. When the voltage difference between VBAT and LED_N is large, when the switch tube M1 and NMOS tube M2 are turned on, the corresponding gate oxide voltage may exceed the maximum gate oxide withstand voltage of the device, which will reduce the reliability of the circuit and affect the performance of the switch control circuit;

[0009] 2) The existing solution has a slow switch control response speed, and the switch control slope of the LED is a fixed value. It does not have the characteristics of dynamic slope control and cannot adapt to the application requirements of different scenarios. In addition, the anti-EMI performance is poor in actual applications.

[0010] In summary, the existing LED switch control cannot meet the requirements of LED light string driver chip performance and power consumption in practical applications. Summary of the invention

[0011] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a slope configurable wide-range input LED drive control circuit and method, which can realize wide-range input LED drive control, improve EMI characteristics, and increase the response speed and reliability of drive control.

[0012] According to the technical solution provided by the present invention, the slope configurable wide-range input LED drive control circuit includes a plurality of LED drive control modules, wherein an LED drive control module drives and controls the working state of an LED unit through a power switch tube, the source terminal of the power switch tube is connected to the LED_N terminal of the LED unit, and the drain terminal of the power switch tube is connected to the LED_P terminal of the LED unit;

[0013] The LED driving control module includes a slope controllable driving module for generating a switch tube driving control signal DRV_G and a switch signal transmission module for loading a required high voltage switch control signal HV_PWM_IN to the slope controllable driving module, wherein a switch control signal reference slope is configured in the slope controllable driving module;

[0014] When generating the switch tube drive control signal DRV_G based on the received high-voltage switch control signal HV_PWM_IN, the slope-controllable drive module configures the rising slope of the high-voltage switch control signal HV_PWM_IN and / or the falling slope of the high-voltage switch control signal HV_PWM_IN using the configured switch control signal reference slope, so as to generate the switch tube drive control signal DRV_G for driving and controlling the switching state of the corresponding power switch tube after performing the required slope configuration based on the switch control signal reference slope.

[0015] For the generated switch tube drive control signal DRV_G, the rising section slope for controlling the switch state change of the power switch tube and the falling section slope for controlling the switch state change of the power switch tube in the switch tube drive control signal DRV_G are both in a smooth changing state.

[0016] The slope controllable driving module includes a controllable slope driving circuit and a switch tube state locking circuit adaptively connected to the controllable slope driving circuit, wherein:

[0017] The switch control signal reference slope is configured in the controllable slope driving circuit. When the controllable slope driving circuit receives the high-voltage switch control signal HV_PWM_IN loaded by the switch signal transmission module, the controllable slope driving circuit configures the rising slope of the high-voltage switch control signal HV_PWM_IN and the falling slope of the high-voltage switch control signal HV_PWM_IN based on the switch control signal reference slope, so as to generate the required switch tube driving control signal DRV_G after the slope configuration;

[0018] The switch state locking circuit locks the level state of the power switch gate based on the high voltage switch control signal HV_PWM_IN and the switch drive control signal DRV_G until the drive control state of the high voltage switch control signal HV_PWM_IN is reversed.

[0019] The controllable slope driving circuit includes a controllable slope reference circuit for configuring a reference slope of a switch control signal and a negative feedback loop for negative feedback regulation of a switch tube drive control signal DRV_G, wherein:

[0020] The controllable slope reference circuit includes a PMOS tube MP1, a PMOS tube MP2, an NMOS tube MN4 and an NMOS tube MN2, the gate end of the PMOS tube MP2 and the gate end of the NMOS tube MN4 receive a high voltage domain switch control signal HV_PWM_IN, and the source end of the PMOS tube MP2, the power supply end of the current source IB1, and the power supply end of the adjustable bias current source IB3 are all connected to the drive control power supply voltage VREG;

[0021] The output end of the current source IB1 is connected to the source end of the PMOS transistor MP1, the gate end of the PMOS transistor MP1 is connected to the drain end of the PMOS transistor MP2, the drain end of the NMOS transistor MN4 and the gate end of the NMOS transistor MN2, the drain end of the PMOS transistor MP1 is connected to the drain end of the NMOS transistor MN2, one end of the capacitor C1 and the gate end of the NMOS transistor MN3, the other end of the capacitor C1, the drain end of the NMOS transistor MN3 and the output end of the adjustable bias current source IB3 are connected to each other to form an SR_REF node;

[0022] The source terminal of the NMOS tube MN4 and the source terminal of the NMOS tube MN3 are both connected to the LED_N terminal of the corresponding LED unit, and the source terminal of the NMOS tube MN2 is grounded through the current source IB2;

[0023] The controllable slope reference circuit is connected to the negative feedback loop through the SR_REF node, and outputs the switch tube drive control signal DRV_G through the negative feedback loop.

[0024] The current I1 output by the current source IB1 is equal to the current I2 output by the current source IB2.

[0025] The negative feedback loop includes an operational amplifier OP1 for forming a unit gain negative feedback, wherein the non-inverting terminal of the operational amplifier OP1 is connected to the SR_REF node, the inverting terminal of the operational amplifier OP1 is connected to the output terminal of the operational amplifier OP1, and the switch tube drive control signal DRV_G is output through the output terminal of the operational amplifier OP1.

[0026] The switch tube state locking circuit includes a hysteresis comparator CMP1, a first signal selector and a second signal selector, wherein:

[0027] The non-inverting terminal of the hysteresis comparator CMP1 receives the switch tube drive control signal DRV_G, and the reference terminal of the hysteresis comparator CMP1 receives the threshold signal DRV_H or the threshold signal DRV_L, so as to compare the switch tube drive control signal DRV_G with the threshold signal DRV_H or the threshold signal DRV_L by using the hysteresis comparator CMP1;

[0028] The output end of the hysteresis comparator CMP1 is adaptively connected to the first signal selector and the second signal selector, and the first signal selector and the second signal selector also receive the high voltage switch control signal HV_PWM_IN;

[0029] When the switch tube drive control signal DRV_G is greater than the threshold signal DRV_H, the hysteresis comparator CMP1 locks the gate terminal of the power switch tube to a high level through the first signal selector, so that the power switch tube is turned on;

[0030] When the switch tube driving control signal DRV_G is less than the threshold signal DRV_L, the hysteresis comparator CMP1 locks the gate terminal of the power switch tube to a low level through the second signal selector, so that the power switch tube is turned off.

[0031] The reference terminal of the hysteresis comparator CMP1 receives the threshold signal DRV_H through the switch SW3 and receives the threshold signal DRV_L through the switch SW4;

[0032] The output end of the first signal selector is connected to the control end of the upper locking switch, and the output end of the second signal selector is connected to the control end of the lower locking switch; one end of the upper locking switch is connected to the output end of the current source IB4, the power supply end of the current source IB4 is connected to the drive control power supply voltage VREG, and the other end of the upper locking switch is connected to one end of the lower locking switch, the gate end of the power switch tube and the output end of the controllable slope driving circuit; the other end of the lower locking switch is connected to the LED_N end of the corresponding LED unit through the current source IB5;

[0033] When the switch tube drive control signal DRV_G is greater than the threshold signal DRV_H, the upper locking switch is turned off by controlling the first signal selector, so as to lock the gate terminal of the power switch tube to a high level by using the current source IB4;

[0034] When the switch tube driving control signal DRV_G is less than the threshold signal DRV_L, the second signal selector controls the lower locking switch to be turned off, so as to use the current source IB5 to lock the gate terminal of the power switch tube to a low level.

[0035] The first signal selector includes a multiplexer MUX1 or a gate circuit first selector, wherein:

[0036] The first selector of the gate circuit includes an XOR gate NXOR1 and an inverter INV1 connected to the XOR gate NXOR1, wherein the XOR gate NXOR1 is connected to the output end of the hysteresis comparator CMP1 and receives the high voltage switch control signal HV_PWM_IN, and the output end of the XOR gate NXOR1 is connected to the input end of the inverter INV1.

[0037] The second signal selector includes a multiplexer MUX2 or a gate circuit second selector, wherein:

[0038] The gate circuit second selector includes an XOR gate XOR1 and an inverter INV2, wherein the XOR gate XOR1 is connected to the output end of the hysteresis comparator CMP1 and receives the high voltage switch control signal HV_PWM_IN, and the output end of the XOR gate XOR1 is connected to the input end of the inverter INV2.

[0039] The upper locking switch includes a switch SW1 or a CMOS switch transmission gate SW5; the lower locking switch includes a switch SW2 or a CMOS switch transmission gate SW6.

[0040] For any LED drive control module, it also includes a high-voltage linear modulation module for providing the required drive control power supply voltage VREG to the slope controllable drive module, wherein:

[0041] The high-voltage linear modulation module generates a drive control supply voltage VREG based on the linear reference voltage HV_SUP and the voltage at the LED_N terminal of the LED unit, wherein the drive control supply voltage VREG is the sum of the voltage at the LED_N terminal of the LED unit and the modulation drive voltage, so that the slope controllable drive module operates under the drive control supply voltage VREG and the corresponding voltage at the LED_N terminal of the LED unit.

[0042] It also includes a charge pump circuit, which is adaptively connected to the corresponding high-voltage linear modulation modules in all LED drive control modules, wherein:

[0043] The charge pump circuit generates a linear reference voltage HV_SUP based on the voltage at the LED_P terminal of the LED unit, and loads the generated linear reference voltage HV_SUP to the high-voltage linear modulation modules in the corresponding LED drive control modules.

[0044] The high-voltage linear modulation module includes a PMOS tube MP10 and a PMOS tube MP20, wherein:

[0045] The source terminal of the PMOS tube MP10 is connected to the source terminal of the PMOS tube MP210 and the drain terminal of the NMOS tube N20, and is connected to the linear reference voltage HV_SUP; the gate terminal of the PMOS tube MP10, the gate terminal of the PMOS tube MP20 and the drain terminal of the PMOS tube MP10 are grounded through the current source IB6;

[0046] The drain terminal of the PMOS tube MP20 is connected to the drain terminal of the NMOS tube MN10, the gate terminal of the NMOS tube MN10 and the gate terminal of the NMOS tube MN20, the source terminal of the NMOS tube MN10 is connected to the LED_N terminal through the resistor R4, the source terminal of the NMOS tube MN20 is connected to one end of the resistor R5 and one end of the capacitor C2, the other end of the resistor R5 and the other end of the capacitor C2 are connected to the LED_N terminal, and the source terminal of the NMOS tube MN20 is connected to the resistor R5 and the capacitor C20 to output the driving control supply voltage VREG.

[0047] The switch signal transmission module receives the low-voltage domain switch control signal PWM_IN_L, converts the received low-voltage domain switch control signal PWM_IN_L into a high-voltage domain switch control signal HV_PWM_IN, and loads the converted high-voltage domain switch control signal HV_PWM_IN to the slope controllable driving module.

[0048] An LED unit includes at least one LED lamp;

[0049] The power switch tube includes an NMOS tube MN1, and the switch tube drive control signal DRV_G generated by the slope controllable drive module is loaded to the gate terminal of the NMOS tube MN1;

[0050] When the switch tube driving control signal DRV_G controls the NMOS tube MN1 to be turned on, the LED unit corresponding to the NMOS tube MN1 is in an off state; when the switch tube driving control signal DRV_G controls the NMOS tube MN1 to be turned off, the LED unit corresponding to the NMOS tube MN1 is in a lit state.

[0051] A slope-configurable wide-range input LED drive control method uses the above-mentioned LED drive control circuit to perform required drive control on any LED unit.

[0052] The advantages of the present invention are as follows: the charge pump circuit and the high-voltage linear modulation module are used to power the slope controllable driving module in the LED driving control module where the high-voltage linear modulation module is located, so that the driving control power supply voltage VREG can be dynamically adjusted based on the voltages of the LED_P terminal and the LED_N terminal of the LED unit, and is always within the safe working voltage range, meeting the wide range power supply requirements; the slope controllable driving module is configured with a switch control signal reference slope, and the rising and falling slopes of the high-voltage domain switch control signal HV_PWM_IN are configured based on the switch control signal reference slope, so that the generated switch tube driving control signal DRV_G does not generate overshoot when driving the power switch tube, thereby improving the EMI characteristics of the driving control LED unit. The charge pump circuit 1 can be connected and coordinated with one LED driving control module or multiple LED driving control modules, thereby increasing the application range of LED driving, reducing the chip area of ​​the driving control, having good dynamic response, and can be widely used in LED driving chips or power management chips. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 It is a circuit schematic diagram of an existing LED switch control circuit.

[0054] Figure 2 This is a circuit block diagram of the LED drive control circuit of the present invention.

[0055] Figure 3 The present invention is a circuit block diagram including multiple LED drive control modules.

[0056] Figure 4 The figure is a schematic diagram of a specific implementation circuit of the slope controllable driving module of the present invention.

[0057] Figure 5 This is a circuit schematic diagram of another specific implementation of the slope controllable driving module of the present invention.

[0058] Figure 6 This is a circuit schematic diagram of the high voltage linear modulation module of the present invention.

[0059] Figure 7 Schematic diagram of the comparison between the switch tube driving control signal DRV_G and the high voltage switch control signal HV_PWM_IN of the present invention.

[0060] Explanation of the reference numerals: 1 - charge pump circuit, 2 - high voltage linear modulation module, 3 - slope controllable driving module, 4 - switch signal transmission module and 5 - LED driving control module. DETAILED DESCRIPTION

[0061] The present invention will be further described below in conjunction with specific drawings and embodiments.

[0062] In order to improve the EMI characteristics during LED driving control, the slope configurable wide-range input LED driving control circuit of the present invention specifically includes: a plurality of LED driving control modules 5, wherein one LED driving control module 5 drives and controls the working state of one LED unit through a power switch tube, the source terminal of the power switch tube is connected to the LED_N terminal of the LED unit, and the drain terminal of the power switch tube is connected to the LED_P terminal of the LED unit;

[0063] The LED driving control module 5 includes a slope controllable driving module 3 for generating a switch tube driving control signal DRV_G and a switch signal transmission module 4 for loading a required high voltage switch control signal HV_PWM_IN to the slope controllable driving module 3, wherein a switch control signal reference slope is configured in the slope controllable driving module 3;

[0064] When generating the switch tube drive control signal DRV_G based on the received high-voltage switch control signal HV_PWM_IN, the slope-controllable driving module 3 uses the configured switch control signal reference slope to configure the rising slope of the high-voltage switch control signal HV_PWM_IN and / or the falling slope of the high-voltage switch control signal HV_PWM_IN, so as to generate the switch tube drive control signal DRV_G for driving and controlling the switching state of the corresponding power switch tube after performing the required slope configuration based on the switch control signal reference slope.

[0065] Specifically, an LED unit generally includes at least one LED lamp, that is, the control of a single LED lamp mentioned in the above description is realized. Of course, in the specific implementation, the number of LED lamps in an LED unit can be more than one, and the number of LED lamps in an LED unit can be selected as needed to meet the actual application requirements. For any LED unit, a power switch tube is generally used to control the working state of the LED unit. When a power switch tube is used to control the working state of an LED unit, the source terminal of the power switch tube is connected to the LED_N terminal of the LED unit, and the drain terminal of the power switch tube is connected to the LED_P terminal of the LED unit, such as Figure 1 The connection coordination shown in the figure is consistent with the existing specific coordination of the power switch tube and the LED unit. Controlling the working state of the LED unit specifically refers to controlling the LED unit to be in a lit state or in a dark state.

[0066] In specific implementation, when the LED driving control module 5 cooperates with the power switch tube, the LED driving control module 5 and the power switch tube are in one-to-one correspondence, that is, the LED driving control module 5 and the LED unit are also in one-to-one correspondence. Figure 2 The figure shows a LED unit, wherein the LED unit includes only one LED lamp, and an LED driving control module 5 is used to correspond to the LED unit; Figure 3 In the figure, it is shown that a plurality of LED units are included, each of which includes an LED lamp. At this time, the number of LED drive control modules 5 is consistent with the number of LED units, and the plurality of LED lamps are connected in series. At this time, there are power switch tubes that are consistent with the number of LED units. The specific connection between the power switch tubes and the LED units is explained below.

[0067] In the embodiment of the present invention, the LED driving control module 5 can adopt the same form. Figure 2 and Figure 3In the embodiment, the LED driving control module 5 at least includes a slope adjustable driving module 3 and a switch signal transmission module 4 adapted to be connected to the slope adjustable driving module 3. Specifically, the slope controllable driving module 3 is used to generate a switch tube driving control signal DRV_G, and the switch signal transmission module 4 is used to load the required high voltage switch control signal HV_PWM_IN to the slope controllable driving module 3 according to actual control requirements, that is, the switch tube driving control signal DRV_G generated by the slope adjustable driving module 3 is based on the high voltage switch control signal HV_PWM_IN, therefore, when the working state of a corresponding LED unit is controlled by the power switch tube, that is, the switch state of the power switch tube is controlled by the slope adjustable driving module 3 under the high voltage switch control signal HV_PWM_IN, thereby realizing the driving control of the working state of the corresponding LED unit. The specific situation of the high voltage switch control signal HV_PWM_IN can be determined according to actual application requirements. The specific situation of the high voltage switch control signal HV_PWM_IN is determined to be consistent with the existing situation, that is, after determining the working state of the LED unit, the high voltage switch control signal HV_PWM_IN corresponding to the working state can be determined.

[0068] In order to improve the EMI characteristics during LED drive control, in an embodiment of the present invention, a switch control signal reference slope needs to be configured in the slope controllable drive module 3. The specific situation of the switch control signal reference slope can be determined according to actual application requirements, that is, corresponding to a certain application scenario, the switch control signal reference slope corresponding to the application scenario is configured in the slope controllable drive module 3, and the configured switch control signal reference slope remains stable in the actual application scenario.

[0069] It can be seen from the above description that the switch tube drive control signal DRV_G generated by the slope-controllable driving module 3 is based on the high-voltage switch control signal HV_PWM_IN. After the switch control signal reference slope is configured in the slope-controllable driving module 3, the slope of the high-voltage switch control signal HV_PWM_IN can be configured using the configured switch control signal reference slope. The slope configuration performed specifically refers to configuring the rising segment slope of the high-voltage switch control signal HV_PWM_IN and / or the falling segment slope of the high-voltage switch control signal HV_PWM_IN, so that the switch tube drive control signal DRV_G is generated according to the high-voltage switch control signal HV_PWM_IN after the rising segment slope and / or the falling segment slope is configured.

[0070] In a specific implementation, for the generated switch tube drive control signal DRV_G, the rising slope of the switch tube drive control signal DRV_G used to control the switch state change of the power switch tube and the falling slope of the switch tube drive control signal DRV_G are both in a smooth change state, so as to meet the requirements of optimizing EMI characteristics. Controlling the switch state change of the power switch tube specifically refers to controlling the power switch tube from the on state to the off state, or controlling the power switch tube from the off state to the on state.

[0071] In the embodiment of the present invention, when the power switch tube is turned on, the LED unit that is connected to the power switch tube in a corresponding manner is in an off state; when the power switch tube is turned off, the LED unit that is connected to the power switch tube in a corresponding manner is in a lit state. Figure 7 In the figure, a is a waveform diagram of the high voltage domain switch control signal HV_PWM_IN, b is a schematic diagram of generating a switch tube drive control signal based on the voltage domain switch control signal HV_PWM_IN, and c is a waveform diagram of generating a switch tube drive control signal DRV_G based on a reference slope of the switch control signal according to the present invention.

[0072] Therefore, by Figure 7 It can be seen from the description that, compared with the prior art, the switch tube drive control signal DRV_G generated by the present invention has a smoother slope change in the rising stage and the falling stage, and the smoothness means that there is no large overshoot in the rising stage and the falling stage of the existing waveform b, which can achieve the purpose of improving the EMI characteristics when controlling the switch state of the power switch tube. In specific implementation, the specific situation of the smoothness can be selected according to needs, that is, different smooth changes can be configured based on the reference slope of the switch control signal, and the specific application requirements can be met. Control the switch state of the power switch tube, that is, control the power switch tube to be in the on state or the off state. In the embodiment of the present invention, the rising section slope and / or the falling section slope of the switch state of the drive control power switch tube are smoothed, so that the EMI characteristics of the corresponding switch state change of the drive control power switch tube can be optimized, that is, when the control power switch tube changes from the on state to the off state, or when it changes from the off state to the on state, it has good EMI characteristics.

[0073] Furthermore, the slope controllable driving module 3 includes a controllable slope driving circuit and a switch tube state locking circuit adaptively connected to the controllable slope driving circuit, wherein:

[0074] The switch control signal reference slope is configured in the controllable slope driving circuit. When the high voltage switch control signal HV_PWM_IN loaded by the switch signal transmission module 4 is received through the controllable slope driving circuit, the controllable slope driving circuit configures the rising slope of the high voltage switch control signal HV_PWM_IN and the falling slope of the high voltage switch control signal HV_PWM_IN based on the switch control signal reference slope, so as to generate the required switch tube driving control signal DRV_G after the slope configuration;

[0075] The switch state locking circuit locks the level state of the power switch gate based on the high voltage switch control signal HV_PWM_IN and the switch drive control signal DRV_G until the drive control state of the high voltage switch control signal HV_PWM_IN is reversed.

[0076] In order to configure the switch control signal reference slope and generate the switch tube drive control signal DRV_G based on the configured switch control signal reference slope, in a specific implementation, the slope controllable drive module 3 includes a controllable slope drive circuit and a switch tube state locking circuit adaptively connected to the controllable slope drive circuit; in a specific implementation, the switch control signal reference slope is configured in the controllable slope drive circuit, and the high voltage domain switch control signal HV_PWM_IN loaded by the switch signal transmission module 4 is received through the controllable slope drive circuit.

[0077] After receiving the high-voltage switch control signal HV_PWM_IN, the controllable slope driving circuit configures the rising slope of the high-voltage switch control signal HV_PWM_IN and the falling slope of the high-voltage switch control signal HV_PWM_IN based on the switch control signal reference slope, that is, generates the switch tube driving control signal DRV_G after configuration.

[0078] In order to improve the stability and reliability of the switch state driving control state of the power switch tube, a switch tube state locking circuit is used to lock the level state of the power switch tube gate. For example, when the level of the power switch tube gate is locked to a high level, for a power switch tube using an NMOS tube, the power switch tube remains in the on state; when the level of the power switch tube gate is locked to a low level, for a power switch tube using an NMOS tube, the power switch tube will be in the off state.

[0079] In specific implementation, when locking the gate level state of the power switch tube, it is necessary to be based on the high-voltage switch control signal HV_PWM_IN and the switch tube drive control signal DRV_G. Specifically, the drive control state of the high-voltage switch control signal HV_PWM_IN is flipped, which specifically refers to the drive control state of the high-voltage switch control signal HV_PWM_IN flipping from the rising stage to the falling stage, or from the falling stage to the rising stage. When the drive control state of the high-voltage switch control signal HV_PWM_IN is flipped, it is necessary to change the state of the gate level of the power switch tube.

[0080] Furthermore, the controllable slope driving circuit includes a controllable slope reference circuit for configuring a reference slope of a switch control signal and a negative feedback loop for negative feedback regulation of the switch tube driving control signal DRV_G, wherein:

[0081] The controllable slope reference circuit includes a PMOS tube MP1, a PMOS tube MP2, an NMOS tube MN4 and an NMOS tube MN2, the gate end of the PMOS tube MP2 and the gate end of the NMOS tube MN4 receive a high voltage domain switch control signal HV_PWM_IN, and the source end of the PMOS tube MP2, the power supply end of the current source IB1, and the power supply end of the adjustable bias current source IB3 are all connected to the drive control power supply voltage VREG;

[0082] The output end of the current source IB1 is connected to the source end of the PMOS transistor MP1, the gate end of the PMOS transistor MP1 is connected to the drain end of the PMOS transistor MP2, the drain end of the NMOS transistor MN4 and the gate end of the NMOS transistor MN2, the drain end of the PMOS transistor MP1 is connected to the drain end of the NMOS transistor MN2, one end of the capacitor C1 and the gate end of the NMOS transistor MN3, the other end of the capacitor C1, the drain end of the NMOS transistor MN3 and the output end of the adjustable bias current source IB3 are connected to each other to form an SR_REF node;

[0083] The source terminal of the NMOS tube MN4 and the source terminal of the NMOS tube MN3 are both connected to the LED_N terminal of the corresponding LED unit, and the source terminal of the NMOS tube MN2 is grounded through the current source IB2;

[0084] The controllable slope reference circuit is connected to the negative feedback loop through the SR_REF node, and outputs the switch tube drive control signal DRV_G through the negative feedback loop.

[0085] Figure 4 and Figure 5, a specific implementation of the controllable slope reference circuit is shown, specifically, the current I1 output by the current source IB1 is equal to the current I2 output by the current source IB2. In addition, the negative feedback loop includes an operational amplifier OP1 for forming a unit gain negative feedback, the non-inverting terminal of the operational amplifier OP1 is connected to the SR_REF node, the inverting terminal of the operational amplifier OP1 is connected to the output terminal of the operational amplifier OP1, and the switch tube drive control signal DRV_G is output through the output terminal of the operational amplifier OP1.

[0086] Figure 4 and Figure 5 In the embodiment, the power switch tube is an NMOS tube MN1, the LED lamp included in the LED unit is LED1, the anode end of LED1 forms the LED_P end, and the cathode end of LED1 forms the LED_N end. The adjustable bias current IB3 can provide a controllable reference signal for the slope change of the rising or falling segment to the power switch tube MN1, that is, the reference slope of the switch control signal can be configured. Therefore, according to the actual application requirements, the current output by the adjustable bias current IB3 can be adjusted to configure the required reference slope of the switch control signal. After the application scenario is determined, the current output by the adjustable bias current IB3 is adjusted to remain fixed, that is, the configured reference slope of the switch control signal is locked.

[0087] The operational amplifier OP1 is used to form a negative feedback loop with unit gain negative feedback, which is used to perform negative feedback regulation on the switch tube drive control signal DRV_G, so that the switch tube drive control signal DRV_G loaded to the gate end of the power switch tube MN1 is the same as the SR_REF node, that is, the required switch tube drive control signal DRV_G is obtained after the slope configuration is realized, thereby achieving the slope control of the switch state of the power switch tube MN1, and improving the EMI characteristics when the power switch tube MN1 is used to drive and control the working state of the LED unit.

[0088] In specific implementation, by setting the sizes of current source IB1, current source IB2 and adjustable bias current IB3 and the size ratio of NMOS tube MN1 and NMOS tube MN3, the slope of NMOS tube MN1 turning on or off can be further controlled and optimized, thereby achieving the purpose of further improving EMI characteristics.

[0089] Furthermore, the switch tube state locking circuit includes a hysteresis comparator CMP1, a first signal selector and a second signal selector, wherein:

[0090] The non-inverting terminal of the hysteresis comparator CMP1 receives the switch tube drive control signal DRV_G, and the reference terminal of the hysteresis comparator CMP1 receives the threshold signal DRV_H or the threshold signal DRV_L, so as to compare the switch tube drive control signal DRV_G with the threshold signal DRV_H or the threshold signal DRV_L by using the hysteresis comparator CMP1;

[0091] The output end of the hysteresis comparator CMP1 is adaptively connected to the first signal selector and the second signal selector, and the first signal selector and the second signal selector also receive the high voltage switch control signal HV_PWM_IN;

[0092] When the switch tube drive control signal DRV_G is greater than the threshold signal DRV_H, the hysteresis comparator CMP1 locks the gate terminal of the power switch tube to a high level through the first signal selector, so that the power switch tube is turned on;

[0093] When the switch tube driving control signal DRV_G is less than the threshold signal DRV_L, the hysteresis comparator CMP1 locks the gate terminal of the power switch tube to a low level through the second signal selector, so that the power switch tube is turned off.

[0094] Specifically, the threshold signal DRV_H and the threshold signal DRV_L can be selected and determined according to the actual scenario. For example, the threshold signal DRV_H and the threshold signal DRV_L can be set to: DRV_H = 0.8*(VREG-V LED_N ), DRV_L=0.2*(VREG-V LED_N ), the hysteresis comparator CMP1 can be used to compare the switch tube driving control signal DRV_G with the threshold signal DRV_H or the threshold signal DRV_L.

[0095] Figure 5 FIG. 1 shows an implementation of setting the threshold signal DRV_H and the threshold signal DRV_L. Figure 5 In the embodiment, the driving control supply voltage VREG is connected to one end of the resistor R1, the other end of the resistor R1 is connected to one end of the resistor R2, and the resistor R2 is connected to the LED_N end of the LED unit through the resistor R3, wherein the threshold signal DRV_H can be obtained by using the node formed by the combination of the resistor R1 and the resistor R2, and the threshold signal DRV_L can be obtained by using the node formed by the combination of the resistor R2 and the resistor R3. Of course, in the specific implementation, other implementation methods can also be used to realize the setting of the threshold signal DRV_H and the threshold signal DRV_L, which can be selected according to the needs to meet the actual application requirements.

[0096] right Figure 4 and Figure 5In the implementation of the medium power switch tube being the NMOS tube MN1, when the switch tube drive control signal DRV_G is greater than the threshold signal DRV_H, the hysteresis comparator CMP1 locks the gate terminal of the power switch tube to a high level through the first signal selector, so that the power switch tube is turned on;

[0097] When the switch tube drive control signal DRV_G is less than the threshold signal DRV_L, the hysteresis comparator CMP1 locks the gate terminal of the power switch tube to a low level through the second signal selector, so that the power switch tube is turned off. Specifically, when the NMOS tube MN1 is turned on, the LED unit corresponding to the NMOS tube MN1 is in an off state; when the NMOS tube MN1 is turned off, the LED unit corresponding to the NMOS tube MN1 is in a lit state.

[0098] In a specific implementation, the first signal selector includes a multiplexer MUX1 or a gate circuit first selector, wherein:

[0099] The first selector of the gate circuit includes an XOR gate NXOR1 and an inverter INV1 connected to the XOR gate NXOR1, wherein the XOR gate NXOR1 is connected to the output end of the hysteresis comparator CMP1 and receives the high voltage switch control signal HV_PWM_IN, and the output end of the XOR gate NXOR1 is connected to the input end of the inverter INV1.

[0100] The second signal selector includes a multiplexer MUX2 or a gate circuit second selector, wherein:

[0101] The gate circuit second selector includes an XOR gate XOR1 and an inverter INV2, wherein the XOR gate XOR1 is connected to the output end of the hysteresis comparator CMP1 and receives the high voltage switch control signal HV_PWM_IN, and the output end of the XOR gate XOR1 is connected to the input end of the inverter INV2.

[0102] Figure 4 , it is shown that the first signal selector uses a multiplexer MUX1, and the second signal selector uses a multiplexer MUX2, Figure 5 In the figure, the first signal selector adopts the first gate circuit selector, and the second signal selector adopts the second gate circuit selector. Of course, in the specific implementation, the first signal selector and the second signal selector can also adopt other implementations, which can be selected according to needs, so as to achieve the required signal selection.

[0103] Further, the reference terminal of the hysteresis comparator CMP1 receives the threshold signal DRV_H through the switch SW3 and receives the threshold signal DRV_L through the switch SW4;

[0104] When the output CMP_OUT of the hysteresis comparator CMP1 is at a high level, the high level output by the hysteresis comparator CMP1 is used to open the switch SW3 and close the switch SW4, so that the reference end of the hysteresis comparator CMP1 is selected to the threshold signal DRV_L;

[0105] When the output CMP_OUT of the hysteresis comparator CMP1 is at a low level, the low level output by the hysteresis comparator CMP1 is used to close the switch SW3 and open the switch SW4, so that the reference end of the hysteresis comparator CMP1 is selected to DRV_H.

[0106] The output end of the first signal selector is connected to the control end of the upper locking switch, and the output end of the second signal selector is connected to the control end of the lower locking switch; one end of the upper locking switch is connected to the output end of the current source IB4, the power supply end of the current source IB4 is connected to the drive control power supply voltage VREG, and the other end of the upper locking switch is connected to one end of the lower locking switch, the gate end of the power switch tube and the output end of the controllable slope driving circuit; the other end of the lower locking switch is connected to the LED_N end of the corresponding LED unit through the current source IB5;

[0107] When the switch tube drive control signal DRV_G is greater than the threshold signal DRV_H, the upper locking switch is turned off by controlling the first signal selector, so as to lock the gate terminal of the power switch tube to a high level by using the current source IB4;

[0108] When the switch tube driving control signal DRV_G is less than the threshold signal DRV_L, the second signal selector controls the lower locking switch to be turned off, so as to use the current source IB5 to lock the gate terminal of the power switch tube to a low level.

[0109] In the embodiment of the present invention, the threshold signal DRV_H or the threshold signal DRV_L can be selected by switches SW3 and SW4. Switches SW3 and SW4 can be CMOS transmission gates, and of course, other controllable switch forms can also be used, which can be selected according to needs.

[0110] In a specific implementation, the upper locking switch includes a switch SW1 or a CMOS switch transmission gate SW5; the lower locking switch includes a switch SW2 or a CMOS switch transmission gate SW6. Figure 4 FIG. 4 shows an implementation in which the upper locking switch uses switch SW1 and the lower locking switch uses switch SW2. Figure 5 The figure shows the implementation of the upper locking switch using the CMOS switch transmission gate SW5 and the lower locking switch using the CMOS switch transmission gate SW6; of course, in the specific implementation, the upper locking switch and the lower locking switch can also adopt other implementation forms, which can be selected according to needs.

[0111] Below Figure 4 The situation of the slope controllable driving module 3 is shown in FIG. 1 , and the specific working process of the slope controllable driving module 3 is specifically described.

[0112] When the high voltage switch control signal HV_PWM_IN changes from low level to high level, the NMOS tube MN2 is turned off, the switch SW1 is disconnected, and the current source IB1 charges the gate terminal of the NMOS tube MN3 through the PMOS tube MP1. At this time, the SR_REF node is discharged through the NMOS tube MN3, and the operational amplifier OP1 modulates the switch tube drive control signal DRV_G to follow the SR_REF node discharge and decrease.

[0113] When V DRV_G (Voltage of switch tube drive control signal DRV_G) <V DRV_L (the voltage of the threshold signal DRV_L), the hysteresis comparator CMP1 outputs a high level, so that the multiplexer MUX2 controls the switch SW2 to turn on, and the current source IB5 discharges the switch tube drive control signal DRV_G, so that the switch tube drive control signal DRV_G is further pulled down and locked at V LED_N (V LED_N is the voltage at the LED_N terminal). At this time, the NMOS tube MN1 used by the power switch tube is turned off. When the NMOS tube MN1 is turned off, the current flows through the LED1, and the LED1 is in the lighting state.

[0114] When the high voltage switch control signal HV_PWM_IN changes from high level to low level, the PMOS tube MP1 is turned off, the switch SW2 is disconnected, and the current source IB1 discharges to the gate terminal of the NMOS tube MN3 through the NMOS tube MN2. At this time, the SR_REF node is charged by the adjustable bias current IB3, and the operational amplifier OP1 modulates the switch tube drive control signal DRV_G to follow the SR_REF node charging increase.

[0115] When V DRV_G >V DRV_H (the voltage of the threshold signal DRV_H), the hysteresis comparator CMP1 outputs a high level, so that the multiplexer MUX1 controls the switch SW1 to turn on, and the current source IB4 charges the switch tube drive control signal DRV_G, so that the switch tube drive control signal DRV_G is further pulled up and locked at VREG. At this time, the NMOS tube MN1 used by the power switch tube is turned on. After the NMOS tube MN1 is turned on, the current flows through the NMOS tube MN1, and the LED1 is in a non-lit state.

[0116] right Figure 5 For the specific situation of the slope controllable driving module 3 shown in FIG, the specific working process can refer to the above description, which will not be repeated here.

[0117] Furthermore, any LED driving control module 5 further includes a high-voltage linear modulation module 2 for providing the required driving control power supply voltage VREG to the slope controllable driving module 3, wherein:

[0118] The high-voltage linear modulation module 2 generates a drive control supply voltage VREG based on the linear reference voltage HV_SUP and the voltage at the LED_N terminal of the LED unit, wherein the drive control supply voltage VREG is the sum of the voltage at the LED_N terminal of the LED unit and the modulation drive voltage, so that the slope controllable drive module 3 operates under the drive control supply voltage VREG and the corresponding voltage at the LED_N terminal of the LED unit.

[0119] Specifically, in order to achieve a wide range of operation, the high-voltage linear modulation module 2 is used to generate the driving control supply voltage VREG required for the slope controllable driving module 3 to work, that is, the high-voltage linear modulation module 2 is also included in the LED driving control module 5. In specific implementation, the high-voltage linear modulation module 2 generates the driving control supply voltage VREG based on the linear reference voltage HV_SUP and the voltage at the LED_N terminal of the LED unit. The driving control supply voltage VREG is the sum of the voltage at the LED_N terminal of the LED unit and the modulation driving voltage. The modulation driving voltage can be 5V. When the modulation driving high voltage is 5V, in the common mode domain of VLED_N, the slope controllable driving module 3 can be designed using conventional 5V devices or 3.3V devices to save the area in the chip. When the slope controllable driving module 3 works under the driving control supply voltage VREG and the corresponding voltage at the LED_N terminal of the LED unit, a wide range of operating voltage intervals can be achieved.

[0120] like Figure 6 As shown, the high voltage linear modulation module 2 includes a PMOS tube MP10 and a PMOS tube MP20, wherein:

[0121] The source terminal of the PMOS tube MP10 is connected to the source terminal of the PMOS tube MP210 and the drain terminal of the NMOS tube N20, and is connected to the linear reference voltage HV_SUP; the gate terminal of the PMOS tube MP10, the gate terminal of the PMOS tube MP20 and the drain terminal of the PMOS tube MP10 are grounded through the current source IB6;

[0122] The drain terminal of the PMOS tube MP20 is connected to the drain terminal of the NMOS tube MN10, the gate terminal of the NMOS tube MN10 and the gate terminal of the NMOS tube MN20, the source terminal of the NMOS tube MN10 is connected to the LED_N terminal through the resistor R4, the source terminal of the NMOS tube MN20 is connected to one end of the resistor R5 and one end of the capacitor C2, the other end of the resistor R5 and the other end of the capacitor C2 are connected to the LED_N terminal, and the source terminal of the NMOS tube MN20 is connected to the resistor R5 and the capacitor C20 to output the driving control supply voltage VREG.

[0123] Specifically, the current source IB6 is transferred from the low voltage domain to the high voltage domain through the PMOS transistor MP10 and mirrored to the PMOS transistor MP20. Through the embedding of the NMOS transistors MN10 and MN2, the following is obtained:

[0124] VREG-V LED_N =I IB6 *R4

[0125] Among them, V LED_N is the voltage at LED_N, I IB6 is the current output by the current source IB6, and R4 is the resistance value of the resistor R4.

[0126] It can be seen from the above description that, through the high-voltage linear modulation module 2, the slope-controllable driving module 3 can dynamically adjust the driving control supply voltage VREG as the reference ground changes as the voltage at the LED_N terminal, thereby realizing a wide range of operating voltage intervals for the slope-controllable driving module 3 and improving the response speed of the slope-controllable driving module 3.

[0127] Furthermore, it also includes a charge pump circuit 1, which is adaptively connected to the corresponding high-voltage linear modulation modules 2 in all LED drive control modules 5, wherein:

[0128] The charge pump circuit 1 generates a linear reference voltage HV_SUP based on the voltage at the LED_P terminal of the LED unit, and loads the generated linear reference voltage HV_SUP to the high-voltage linear modulation modules 2 in the corresponding LED drive control modules 5 .

[0129] like Figure 1 , Figure 2 and Figure 3As shown, when driving and controlling the LED unit, a charge pump circuit 1 is generally required, wherein the charge pump circuit 1 operates at the power supply voltage VDD and can boost the voltage at the LED_P terminal of the LED unit, thereby generating a linear reference voltage HV_SUP. After the charge pump circuit 1 boosts the voltage at the LED_P terminal to the linear reference voltage HV_SUP, there is sufficient driving voltage margin when driving the LED unit, ensuring that the power switch tube can be fully turned on or off under any conditions.

[0130] During specific implementation, the charge pump circuit 1 may adopt an existing commonly used driving method, which may be selected according to specific needs, so as to meet the requirement of boosting the voltage at the LED_P terminal of the LED unit and generating the linear reference voltage HV_SUP.

[0131] Figure 2 In FIG. 1 , the charge pump circuit 1 is connected to an LED drive control module 5 in an adaptive manner. Figure 3 2 is an implementation of a charge pump circuit 1 adapted to be connected to multiple LED drive control modules 5. When adapted to be connected to multiple LED drive control modules 5, it is adapted to be connected to the high-voltage linear modulation module 2 in the LED drive control module 5 to provide the required linear reference voltage HV_SUP. Figure 3 In the embodiment, LED00 is used to form an LED unit, and LED0 is used to form another LED unit. At this time, the power switch tubes are NMOS tube MN00 and NMOS tube MN0, respectively, wherein NMOS tube MN00 corresponds to LED00, and NMOS tube MN0 corresponds to LED0.

[0132] Figure 3 In the embodiment, the anode terminal of LED00 is connected to the drain terminal of NMOS tube MN00 to form LED2_P terminal, the cathode terminal of LED00 is connected to LED2_N terminal and the anode terminal of LED0, the cathode terminal of LED0 is connected to the source terminal of NMOS tube MN0 to form LED1_N terminal, and the drain terminal of NMOS tube NM0 is connected to LED2_N terminal. At this time, the voltage of LED2_P terminal is increased by charge pump circuit 1.

[0133] Furthermore, the switch signal transmission module 4 receives the low-voltage domain switch control signal PWM_IN_L, converts the received low-voltage domain switch control signal PWM_IN_L into a high-voltage domain switch control signal HV_PWM_IN, and loads the converted high-voltage domain switch control signal HV_PWM_IN to the slope controllable driving module 3 .

[0134] In the embodiment of the present invention, the switch signal transmission module 4 is used to realize signal conversion and transmission, that is, to convert the low-voltage domain switch control signal PWM_IN_L into the high-voltage domain switch control signal HV_PWM_IN. The low-voltage domain switch control signal PWM_IN_L can be a signal generated at the low-voltage control end, which is specifically related to the required control scenario requirements. Specifically, the high-voltage domain switch control signal HV_PWM_IN can be obtained by using the conversion means commonly used in the technical field. The switch signal transmission module 4 can specifically select the existing commonly used form, which is based on the conversion and transmission of the signal, and will not be repeated here.

[0135] In summary, the slope-configurable wide-range input LED drive control method of the present invention uses the above-mentioned LED drive control circuit to perform the required drive control on any LED unit.

[0136] Specifically, the LED unit, and the method and process of using the LED drive control circuit to perform the required drive control can all refer to the above description, which will not be repeated here.

[0137] It can be seen from the above description that the present invention utilizes the charge pump circuit 1 and the high-voltage linear modulation module 2 to power the slope controllable driving module 3 in the LED driving control module 5 where the high-voltage linear modulation module 2 is located, so that the driving control supply voltage VREG can be dynamically adjusted based on the voltages at the LED_P and LED_N terminals of the LED unit, and is always within a safe operating voltage range, thereby meeting a wide range of power supply requirements.

[0138] The slope controllable driving module 3 is configured with a switch control signal reference slope, and the rising slope and falling slope of the high voltage switch control signal HV_PWM_IN are configured based on the switch control signal reference slope, so that the generated switch tube drive control signal DRV_G will not produce overshoot when driving the power switch tube, thereby improving the EMI characteristics of the drive control LED unit.

[0139] The charge pump circuit 1 can be connected and cooperated with one LED drive control module 5 or multiple LED drive control modules 5, which increases the application scope of LED drive, reduces the chip area of ​​drive control, has good dynamic response, and can be widely used in LED drive chips or power management chips.

Claims

1. A slope configurable wide range input LED drive control circuit, characterized in that: It comprises a plurality of LED drive control modules (5), wherein one LED drive control module (5) drives and controls the working state of an LED unit through a power switch tube, the source terminal of the power switch tube is connected to the LED_N terminal of the LED unit, and the drain terminal of the power switch tube is connected to the LED_P terminal of the LED unit; The LED drive control module (5) comprises a slope controllable drive module (3) for generating a switch tube drive control signal DRV_G and a switch signal transmission module (4) for loading a required high voltage switch control signal HV_PWM_IN to the slope controllable drive module (3), wherein a switch control signal reference slope is configured in the slope controllable drive module (3); When generating a switch tube drive control signal DRV_G based on the received high voltage switch control signal HV_PWM_IN, the slope controllable drive module (3) uses the configured switch control signal reference slope to configure the rising section slope of the high voltage switch control signal HV_PWM_IN and / or the falling section slope of the high voltage switch control signal HV_PWM_IN, so as to generate a switch tube drive control signal DRV_G for driving and controlling the switch state of the corresponding power switch tube after performing the required slope configuration based on the switch control signal reference slope; Any LED drive control module (5) further comprises a high-voltage linear modulation module (2) for providing the slope-controllable drive module (3) with a required drive control power supply voltage VREG, wherein: The high-voltage linear modulation module (2) generates a driving control supply voltage VREG based on a linear reference voltage HV_SUP and a voltage at a terminal LED_N of the LED unit, wherein the driving control supply voltage VREG is the sum of the voltage at a terminal LED_N of the LED unit and a modulation driving voltage, so that the slope controllable driving module (3) operates under the driving control supply voltage VREG and a voltage corresponding to the terminal LED_N of the LED unit; The high-voltage linear modulation module (2) comprises a PMOS tube MP10 and a PMOS tube MP20, wherein: The source terminal of the PMOS tube MP10 is connected to the source terminal of the PMOS tube MP210 and the drain terminal of the NMOS tube N20, and is connected to the linear reference voltage HV_SUP; the gate terminal of the PMOS tube MP10, the gate terminal of the PMOS tube MP20 and the drain terminal of the PMOS tube MP10 are grounded through the current source IB6; The drain terminal of the PMOS tube MP20 is connected to the drain terminal of the NMOS tube MN10, the gate terminal of the NMOS tube MN10 and the gate terminal of the NMOS tube MN20, the source terminal of the NMOS tube MN10 is connected to the LED_N terminal through the resistor R4, the source terminal of the NMOS tube MN20 is connected to one end of the resistor R5 and one end of the capacitor C2, the other end of the resistor R5 and the other end of the capacitor C2 are connected to the LED_N terminal, and the source terminal of the NMOS tube MN20 is connected to the resistor R5 and the capacitor C20 to output the driving control supply voltage VREG.

2. The slope configurable wide range input LED drive control circuit according to claim 1, characterized in that: For the generated switch tube drive control signal DRV_G, the rising section slope for controlling the switch state change of the power switch tube and the falling section slope for controlling the switch state change of the power switch tube in the switch tube drive control signal DRV_G are both in a smooth changing state.

3. The slope configurable wide range input LED drive control circuit according to claim 2, characterized in that: The slope controllable driving module (3) comprises a controllable slope driving circuit and a switch tube state locking circuit adaptively connected to the controllable slope driving circuit, wherein: The switch control signal reference slope is configured in a controllable slope driving circuit. When the controllable slope driving circuit receives the high voltage switch control signal HV_PWM_IN loaded by the switch signal transmission module (4), the controllable slope driving circuit configures the rising slope of the high voltage switch control signal HV_PWM_IN and the falling slope of the high voltage switch control signal HV_PWM_IN based on the switch control signal reference slope, so as to generate the required switch tube drive control signal DRV_G after the slope configuration; The switch state locking circuit locks the level state of the power switch gate based on the high voltage switch control signal HV_PWM_IN and the switch drive control signal DRV_G until the drive control state of the high voltage switch control signal HV_PWM_IN is reversed.

4. The slope configurable wide range input LED drive control circuit according to claim 3, characterized in that: The controllable slope driving circuit includes a controllable slope reference circuit for configuring a reference slope of a switch control signal and a negative feedback loop for negative feedback regulation of a switch tube drive control signal DRV_G, wherein: The controllable slope reference circuit includes a PMOS tube MP1, a PMOS tube MP2, an NMOS tube MN4 and an NMOS tube MN2, the gate end of the PMOS tube MP2 and the gate end of the NMOS tube MN4 receive a high voltage domain switch control signal HV_PWM_IN, and the source end of the PMOS tube MP2, the power supply end of the current source IB1, and the power supply end of the adjustable bias current source IB3 are all connected to the drive control power supply voltage VREG; The output end of the current source IB1 is connected to the source end of the PMOS transistor MP1, the gate end of the PMOS transistor MP1 is connected to the drain end of the PMOS transistor MP2, the drain end of the NMOS transistor MN4 and the gate end of the NMOS transistor MN2, the drain end of the PMOS transistor MP1 is connected to the drain end of the NMOS transistor MN2, one end of the capacitor C1 and the gate end of the NMOS transistor MN3, the other end of the capacitor C1, the drain end of the NMOS transistor MN3 and the output end of the adjustable bias current source IB3 are connected to each other to form an SR_REF node; The source terminal of the NMOS tube MN4 and the source terminal of the NMOS tube MN3 are both connected to the LED_N terminal of the corresponding LED unit, and the source terminal of the NMOS tube MN2 is grounded through the current source IB2; The controllable slope reference circuit is connected to the negative feedback loop through the SR_REF node, and outputs the switch tube drive control signal DRV_G through the negative feedback loop.

5. The slope configurable wide range input LED drive control circuit according to claim 4, characterized in that: The current I1 output by the current source IB1 is equal to the current I2 output by the current source IB2.

6. The slope configurable wide range input LED drive control circuit according to claim 4, characterized in that: The negative feedback loop includes an operational amplifier OP1 for forming a unit gain negative feedback, wherein the non-inverting terminal of the operational amplifier OP1 is connected to the SR_REF node, the inverting terminal of the operational amplifier OP1 is connected to the output terminal of the operational amplifier OP1, and the switch tube drive control signal DRV_G is output through the output terminal of the operational amplifier OP1.

7. The slope configurable wide range input LED drive control circuit according to claim 3, characterized in that: The switch tube state locking circuit includes a hysteresis comparator CMP1, a first signal selector and a second signal selector, wherein: The non-inverting terminal of the hysteresis comparator CMP1 receives the switch tube drive control signal DRV_G, and the reference terminal of the hysteresis comparator CMP1 receives the threshold signal DRV_H or the threshold signal DRV_L, so as to compare the switch tube drive control signal DRV_G with the threshold signal DRV_H or the threshold signal DRV_L by using the hysteresis comparator CMP1; The output end of the hysteresis comparator CMP1 is adaptively connected to the first signal selector and the second signal selector, and the first signal selector and the second signal selector also receive the high voltage switch control signal HV_PWM_IN; When the switch tube drive control signal DRV_G is greater than the threshold signal DRV_H, the hysteresis comparator CMP1 locks the gate terminal of the power switch tube to a high level through the first signal selector, so that the power switch tube is turned on; When the switch tube driving control signal DRV_G is less than the threshold signal DRV_L, the hysteresis comparator CMP1 locks the gate terminal of the power switch tube to a low level through the second signal selector, so that the power switch tube is turned off.

8. The slope configurable wide range input LED drive control circuit according to claim 7, characterized in that: The reference terminal of the hysteresis comparator CMP1 receives the threshold signal DRV_H through the switch SW3 and receives the threshold signal DRV_L through the switch SW4; The output end of the first signal selector is connected to the control end of the upper locking switch, and the output end of the second signal selector is connected to the control end of the lower locking switch; one end of the upper locking switch is connected to the output end of the current source IB4, the power supply end of the current source IB4 is connected to the drive control power supply voltage VREG, and the other end of the upper locking switch is connected to one end of the lower locking switch, the gate end of the power switch tube and the output end of the controllable slope driving circuit; the other end of the lower locking switch is connected to the LED_N end of the corresponding LED unit through the current source IB5; When the switch tube drive control signal DRV_G is greater than the threshold signal DRV_H, the upper locking switch is turned off by controlling the first signal selector, so as to lock the gate terminal of the power switch tube to a high level by using the current source IB4; When the switch tube driving control signal DRV_G is less than the threshold signal DRV_L, the second signal selector controls the lower locking switch to be turned off, so as to use the current source IB5 to lock the gate terminal of the power switch tube to a low level.

9. The slope configurable wide range input LED drive control circuit according to claim 7, characterized in that: The first signal selector includes a multiplexer MUX1 or a gate circuit first selector, wherein: The first selector of the gate circuit includes an XOR gate NXOR1 and an inverter INV1 connected to the XOR gate NXOR1, wherein the XOR gate NXOR1 is connected to the output end of the hysteresis comparator CMP1 and receives the high voltage switch control signal HV_PWM_IN, and the output end of the XOR gate NXOR1 is connected to the input end of the inverter INV1.

10. The slope configurable wide range input LED drive control circuit according to claim 7, characterized in that: The second signal selector includes a multiplexer MUX2 or a gate circuit second selector, wherein: The gate circuit second selector includes an XOR gate XOR1 and an inverter INV2, wherein the XOR gate XOR1 is connected to the output end of the hysteresis comparator CMP1 and receives the high voltage switch control signal HV_PWM_IN, and the output end of the XOR gate XOR1 is connected to the input end of the inverter INV2.

11. The slope configurable wide range input LED drive control circuit according to claim 8, characterized in that: The upper locking switch includes a switch SW1 or a CMOS switch transmission gate SW5; the lower locking switch includes a switch SW2 or a CMOS switch transmission gate SW6.

12. The slope-configurable wide-range input LED drive control circuit according to any one of claims 1 to 11, characterized in that: It also includes a charge pump circuit (1), which is adaptively connected to the corresponding high-voltage linear modulation modules (2) in all LED drive control modules (5), wherein: The charge pump circuit (1) generates a linear reference voltage HV_SUP based on the voltage at the LED_P terminal of the LED unit, and loads the generated linear reference voltage HV_SUP to the high-voltage linear modulation modules (2) in the corresponding LED drive control modules (5).

13. The slope-configurable wide-range input LED drive control circuit according to any one of claims 1 to 11, characterized in that: The switch signal transmission module (4) receives a low-voltage domain switch control signal PWM_IN_L, converts the received low-voltage domain switch control signal PWM_IN_L into a high-voltage domain switch control signal HV_PWM_IN, and loads the converted high-voltage domain switch control signal HV_PWM_IN to the slope controllable drive module (3).

14. The slope-configurable wide-range input LED drive control circuit according to any one of claims 1 to 11, characterized in that: An LED unit includes at least one LED lamp; The power switch tube comprises an NMOS tube MN1, and a switch tube drive control signal DRV_G generated by a slope controllable drive module (3) is loaded onto a gate terminal of the NMOS tube MN1; When the switch tube driving control signal DRV_G controls the NMOS tube MN1 to be turned on, the LED unit corresponding to the NMOS tube MN1 is in an off state; when the switch tube driving control signal DRV_G controls the NMOS tube MN1 to be turned off, the LED unit corresponding to the NMOS tube MN1 is in a lit state.

15. A slope configurable wide range input LED drive control method, characterized in that: For any LED unit, the LED drive control circuit according to any one of claims 1 to 14 is used to perform the required drive control.

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