Simple electric bicycle LED constant-current driving circuit capable of switching high beam and low beam

Abstract

The utility model discloses an electric bicycle LED constant-current driving circuit capable of simply switching high and low beams. The electric bicycle LED constant-current driving circuit comprises a power input module, a switch switching circuit module, an LED chip driving circuit module and an LED load circuit module, the power supply input module is connected with the switch switching circuit module, the switch switching circuit module is connected with the LED chip driving circuit module, the LED chip driving circuit module is connected with the LED load circuit module, and the switch switching circuit module is connected with the LED load circuit module. The switch switching circuit module comprises a single-pole three-throw switch SW1 and is provided with three working gears of low beam, high beam and closing, high beam and low beam switching of the electric bicycle can be conveniently achieved, meanwhile, the device has the advantages of being simple in structure, low in cost and high in reliability, and the lighting requirement for safe driving of the electric bicycle at night is met.

Description

Technical Field

[0001] This utility model relates to the field of circuit technology, specifically to a simple high / low beam switching LED constant current drive circuit for electric bicycles. Background Technology

[0002] With the increasing number of electric bicycles on the road, their nighttime lighting systems have become crucial. During actual riding, riders need to flexibly switch between high and low beams according to road conditions to ensure their own safety and the safety of others. Existing high / low beam switching circuits are often complex in structure and expensive, failing to meet the market demand for cost-effective, stable, and reliable electric bicycle lighting systems. Therefore, developing a low-cost, stable, and reliable simplified high / low beam switching LED driver circuit for electric bicycles is of significant practical importance. Utility Model Content

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing a simple LED constant current drive circuit for switching between high and low beams in electric bicycles, thereby solving the problems of complex structure and high cost of existing high and low beam switching circuits.

[0004] This utility model provides a simple LED constant current drive circuit for electric bicycles with high / low beam switching, comprising: a power input module, a switch switching circuit module, an LED chip driver circuit module, and an LED load circuit module; the power input module is connected to the switch switching circuit module, the switch switching circuit module is connected to the LED chip driver circuit module, the LED chip driver circuit module is connected to the LED load circuit module, and the switch switching circuit module is connected to the LED load circuit module; the switch switching circuit module includes a single-pole three-throw switch SW1, which has three working positions: low beam, high beam, and off, and a common terminal; the power input module is connected to the common terminal, and the low beam and high beam working positions are connected to the LED chip driver circuit module and the LED load circuit module.

[0005] Furthermore, the power input module includes a control converter that sets the input voltage to DC12V.

[0006] Furthermore, the LED chip driving circuit module includes a driving chip, which has pins VIN, CS, D, and NC; pin VIN is a power input pin used to receive DC12V power input; pin CS is an output current sampling pin used to control the current output in the circuit; pin D is a drive output pin connected to the LED load circuit module; and pin NC is an unused pin on the chip.

[0007] Furthermore, the driver chip is an LM9003B chip.

[0008] Further, the LED load circuit module includes LED1, LED2, LED3, diodes D1 and D2, resistors R1, R2, R3, R4, R4A, R5, and MOSFET Q1; the high beam mode of the single-pole three-throw switch SW1 is connected to diode D1; one end of LED1 and LED2 connected in parallel is connected in series with diode D1, and the other end is connected to pin D of the driver chip; the low beam mode of the single-pole three-throw switch SW1 is connected to LED3, and LED3 is connected to pin D of the driver chip; one end of diode D2 is connected between the high beam mode of the single-pole three-throw switch SW1 and diode D1, and the other end of diode D2... One end of resistor R1 is connected between the low beam position of single-pole three-throw switch SW1 and LED3; one end of resistor R5 is connected between diode D2 and LED3, and the other end of resistor R5 is connected to pin VIN of the driver chip; one end of resistor R1 is connected between the low beam position of single-pole three-throw switch SW1 and diode D2, and the other end of resistor R1 is connected to one end of resistor R2, and the other end of resistor R2 is connected to GND; MOSFET Q1 is connected between resistors R1 and R2, one end of resistor R3, and GND; the other end of resistor R3 is connected to pin CS of the driver chip; resistors R4 and R4A are connected in parallel, with one end connected to pin CS of the driver chip and the other end connected to GND.

[0009] This invention offers the following advantages: It provides a simple LED constant current drive circuit for electric bicycles with high / low beam switching. The switching between high and low beams can be achieved using a simple single-pole three-throw switch SW1, allowing riders to easily and quickly switch lighting modes according to road conditions, thus improving the user experience. The circuit uses common and inexpensive electronic components, such as LM9003B chips, ordinary diodes, MOSFETs, and resistors. While ensuring functionality, this effectively reduces manufacturing costs, facilitating large-scale application and promotion of the product. Attached Figure Description

[0010] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 This is the overall framework diagram of the simple high / low beam switching LED constant current drive circuit for electric bicycles according to this utility model;

[0012] Figure 2 This is a detailed circuit diagram of the simplified high / low beam switching LED constant current drive circuit for electric bicycles according to this utility model. Detailed Implementation

[0013] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be pointed out that the following detailed description is illustrative and intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0014] Please see Figures 1 to 2 This utility model provides a simple LED constant current drive circuit for electric bicycles with high / low beam switching, comprising: a power input module, a switch switching circuit module, an LED chip driver circuit module, and an LED load circuit module. The power input is DC12V, and the ground terminal is GND. The power input module is connected to the switch switching circuit module, the switch switching circuit module is connected to the LED chip driver circuit module, the LED chip driver circuit module is connected to the LED load circuit module, and the switch switching circuit module is connected to the LED load circuit module.

[0015] Specifically, in the power input module, the electric bicycle's battery uses its own control converter to ensure that the voltage input to the headlight section is DC12V.

[0016] Specifically, the switch switching circuit module includes a single-pole three-throw switch SW1. SW1 has three operating positions: low beam, high beam, and off, as well as a common terminal. The power input module is connected to the common terminal, and the low beam and high beam operating positions are connected to the LED chip driver circuit module and the LED load circuit module, respectively. When SW1 is switched to the low beam position, the circuit connects to the low beam lighting circuit; when switched to the high beam position, the circuit connects to the high beam lighting circuit; and when lighting is not needed during the day, it can be switched to the off position.

[0017] Specifically, the LED chip driver circuit module uses the LM9003B chip as the core driver chip. This driver chip has pins VIN, CS, D, and NC. Pin VIN is the power input pin, used to receive DC12V power input; pin CS is the output current sampling pin, used to control the current output in the circuit; pin D is the drive output pin, connected to the LED load circuit module; and pin NC is an unused pin on the chip.

[0018] Specifically, the LED load circuit module includes LED1, LED2, LED3, diode D1, diode D2, resistor R1, resistor R2, resistor R3, resistor R4, resistor R4A, resistor R5, and MOSFET Q1; LED1, LED2, and LED3 are high-power 9V LEDs.

[0019] The high beam mode of the single-pole three-throw switch SW1 is connected to diode D1; LED1 and LED2 are connected in parallel, with one end connected in series with diode D1 and the other end connected to pin D of the driver chip; the low beam mode of the single-pole three-throw switch SW1 is connected to LED3, which is also connected to pin D of the driver chip; one end of diode D2 is connected between the high beam mode of the single-pole three-throw switch SW1 and diode D1, and the other end of diode D2 is connected between the low beam mode of the single-pole three-throw switch SW1 and LED3; one end of resistor R5 is connected between diode D2 and LED. Between D3, the other end of resistor R5 is connected to the VIN pin of the driver chip; one end of resistor R1 is connected between the low beam working position of the single-pole three-throw switch SW1 and diode D2, the other end of resistor R1 is connected to one end of resistor R2, and the other end of resistor R2 is connected to the GND terminal; MOSFET Q1 is connected between resistors R1 and R2, one end of resistor R3, and the GND terminal; the other end of resistor R3 is connected to the CS pin of the driver chip; resistors R4 and R4A are connected in parallel, one end of which is connected to the CS pin of the driver chip, and the other end is connected to the GND terminal.

[0020] In high beam mode, LED1, LED2, and LED3 all operate; in low beam mode, only LED3 operates. Diodes D1 and D2 ensure unidirectional current flow while also guaranteeing consistent voltage across all outputs during high beam operation. Furthermore, the circuit includes resistors R1, R2, R3, R4, R4A, and MOSFET Q1. These components work together to regulate and control the circuit's current and voltage.

[0021] The working principle of the simple high / low beam switching LED constant current drive circuit for electric bicycles of this utility model in low beam mode and high beam mode is as follows:

[0022] Low Beam Mode: When the single-pole three-throw switch SW1 is set to the low beam position, the DC 12V power supply is connected to the circuit through the low beam line. The power supply passes through resistor R5 and is input to the VIN pin of the LED constant current driver chip LM9003B. Based on its internal circuit structure and the parameters of external resistors and other components, the chip outputs a suitable drive current through pin D to drive LED3 to emit light, thus achieving the low beam illumination function. At this time, resistors R4 and R4A in the circuit participate in current regulation to ensure stable operation of LED3.

[0023] High Beam Mode: When the single-pole three-throw switch SW1 is switched to the high beam position, the DC12V power supply is connected to the circuit through the high beam line. The power supply passes through diode D1 to power LED1 and LED2. Another path passes through diode D2 and splits into two: one path goes through resistor R5 and is input to the VIN pin of the LED constant current driver chip LM9003B; the other path goes to LED3. The chip outputs drive current through pin D, simultaneously driving LED1, LED2, and LED3, which together achieve the high beam illumination function. At this time, resistors R1, R2, R3, R4, R4A, and MOSFET Q1 all participate in current regulation. Because of the involvement of MOSFET Q1 in high beam mode, when MOSFET Q1 is turned on, resistors R3, R4, and R4A are connected in parallel, resulting in a smaller resistance value. This allows the LM9003B chip to output a larger current, meaning a larger output current during high beam operation.

[0024] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0025] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A simple LED constant current drive circuit for switching between high and low beams in electric bicycles, characterized in that, include: Power input module, switch switching circuit module, LED chip driver circuit module and LED load circuit module; The power input module is connected to the switch switching circuit module, the switch switching circuit module is connected to the LED chip driver circuit module, the LED chip driver circuit module is connected to the LED load circuit module, and the switch switching circuit module is connected to the LED load circuit module. The switch switching circuit module includes a single-pole three-throw switch SW1, which has three working positions: low beam, high beam, and off, as well as a common terminal. The power input module is connected to the common terminal, and the low beam and high beam working positions are connected to the LED chip driver circuit module and the LED load circuit module.

2. The simplified high / low beam switching LED constant current drive circuit for electric bicycles as described in claim 1, characterized in that, The power input module includes a control converter that sets the input voltage to DC 12V.

3. The simplified high / low beam switching LED constant current drive circuit for electric bicycles as described in claim 2, characterized in that, The LED chip driving circuit module includes a driving chip, which has pins VIN, CS, D and NC. The VIN pin is the power input pin, used to receive DC12V power input; the CS pin is the output current sampling pin, used to control the current output in the circuit; the D pin is the drive output pin, connected to the LED load circuit module; and the NC pin is an unused pin on the chip.

4. The simplified high / low beam switching LED constant current drive circuit for electric bicycles as described in claim 3, characterized in that, The driver chip is an LM9003B chip.

5. The simplified high / low beam switching LED constant current drive circuit for electric bicycles as described in claim 4, characterized in that, The LED load circuit module includes LED1, LED2, LED3, diode D1, diode D2, resistor R1, resistor R2, resistor R3, resistor R4, resistor R4A, resistor R5, and MOSFET Q1; The high beam mode of the single-pole triple-throw switch SW1 is connected to diode D1; LED1 and LED2 are connected in parallel, with one end connected in series with diode D1 and the other end connected to pin D of the driver chip; the low beam mode of the single-pole triple-throw switch SW1 is connected to LED3, which is also connected to pin D of the driver chip; one end of diode D2 is connected between the high beam mode of the single-pole triple-throw switch SW1 and diode D1, and the other end of diode D2 is connected between the low beam mode of the single-pole triple-throw switch SW1 and LED3; one end of resistor R5 is connected between diode D2 and... Between LED3, the other end of resistor R5 is connected to the VIN pin of the driver chip; one end of resistor R1 is connected between the low beam position of the single-pole three-throw switch SW1 and diode D2, the other end of resistor R1 is connected to one end of resistor R2, and the other end of resistor R2 is connected to the GND terminal; MOSFET Q1 is connected between resistors R1 and R2, one end of resistor R3, and the GND terminal; the other end of resistor R3 is connected to the CS pin of the driver chip; resistors R4 and R4A are connected in parallel, one end of which is connected to the CS pin of the driver chip, and the other end is connected to the GND terminal.

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