Difficulties of electrostatic surge in car atmosphere lights

As the name implies, car atmosphere lights are lighting that enhance the atmosphere in the car, and are a manifestation of the emotional design of the car interior. Generally, there are two types of lights: warm colors (red, etc.) and cool colors (blue, purple, etc.). When turned on at night, they are gorgeous and romantic, creating a mood in the car, making the journey not so boring, and giving people a unique driving experience.

Regarding the surge protection of automotive ambient lights, Shanghai Leimao EMC brother analyzed the difficulties in the following aspects:

1. Complex electrical environment: The electrical system of a car is relatively complex, with various interference sources, such as the ignition system, motors, electronic equipment, etc., which may pose challenges to the surge protection of the ambient light.

2. Voltage fluctuations: When the car is running, the power supply voltage may fluctuate greatly, such as when starting the engine or switching on and off electrical equipment. This requires the surge protection device to effectively cope with these voltage changes to prevent damage to the ambient light.

3. Multi-channel loads: Car ambient lights are usually composed of multiple light strips or bulbs, and each load needs to be protected separately. This increases the complexity and cost of the protection circuit.

4. Reliability requirements: The automotive environment has high reliability requirements for electronic equipment. Surge protection devices must be able to work stably in long-term use and not be affected by factors such as temperature, humidity and vibration.

5. Electromagnetic compatibility: The ambient light system needs to coexist with other electronic devices and cannot interfere with the vehicle's wireless communication system (such as Bluetooth, GPS, etc.). Therefore, the surge protection design needs to consider electromagnetic compatibility issues.

6. Standards and regulations: The automotive industry has strict standards and regulations, and surge protection designs need to comply with these requirements to ensure safety and compatibility

7. Cost and size constraints: In automotive applications, cost and size are usually important considerations. Surge protection devices need to meet protection requirements while minimizing size and cost. How to choose the right device to meet the full set of 7637-2 tests and load dump requirements of car manufacturers? How to select Lin line protection TVS?

Despite these difficulties, Shanghai Leimao can assist electronic engineers in taking some measures to improve the effect of surge protection for ambient lights, such as helping to select appropriate surge protection devices, optimizing circuit design, and conducting rigorous testing. If you are conducting related design or research, it is recommended that you have an in-depth discussion with a professional Shanghai Leimao EMC guy to ensure the effectiveness and reliability of the surge protection solution.

The following is the electrostatic surge protection solution for atmosphere lights for reference

1. The following is a series of LED driver automotive products from a well-known brand. It is recommended to add an ESD diode to the driver power supply to protect the driver chip from electrostatic surges.

2. This solution is the automotive-grade capacitive touch SoC chip TCAE11, which is used to realize functions such as smart buttons or sliders. It is suitable for various application scenarios such as in-car reading lights, ambient lights, central control, air conditioning control, steering wheels, door handles, etc. In this solution, an ESD diode is also required at the power input end to protect the control safety of the back-end SoC chip and ambient lights.

ESD Diode Selection

Advantages of power supply line selection: small package, suitable for small installation space in the car. High surge current IPP, high anti-static ±30kV (air), ±30kV (contact).

For LIN line protection, the 18/24 asymmetric voltage ESD diode PESD1LIN is preferred, and a high-power 24V bidirectional device can also be selected.