- The use of LED in automotive lighting has increased the visibility of the driver
- The average life of an LED bulb is of up to 42 times the life of an incandescent bulb
The LED technology is gradually finding its way into automobiles. The use of LED devices in automotive lighting has increased the visibility to the driver. This also ensures more road safety when compared to the traditional lighting lamps used in automobiles.
The use of LED introduced some sophisticated challenges to the circuit designers working in the automotive industry. These challenges include designing a complex schematic. An LED array can be used in automobiles. This levels the amount of brightness being provided by the conventional headlight lamps.
Automotive lighting applications can be divided into three categories. These categories are exterior front, exterior rear, and interior lighting. There is a room for improvement at the exterior front which can improve the visibility of the user. This article highlights the advantages of using LED lighting for the exterior front.
Why Use LEDs in automotive applications?
There are two key parameters which support the use of LED in automotive applications. First, LEDs are more efficient than the older incandescent bulbs used in the vehicles. Incandescent bulbs required a huge amount of voltage and current parameters to glow. On the contrary, LED consumes less power for the same or greater illumination intensity. It is observed that LEDs are up to six times more efficient than the incandescent bulbs they replace in vehicles.
The other key parameter is the long service life of an LED when compared to an incandescent bulb. The average life of an LED bulb is of up to 42 times the life of an incandescent bulb. This yields to the service life of the LED to be more than 50000 hours.
Special drivers are needed to operate the LEDs. One driver IC can typically handle a cluster of multiple LEDs. The drivers are current sources with appropriate drive and interface circuits. The typical arrangement consists of connecting the LED in a series configuration. Using this configuration, all the LEDs receive the same current. This is essential to ensure the uniform color and brightness of the lights.
LED drivers are essential dc-dc converters. They are interfaced with the vehicle’s control unit using a CAN interface. This helps the control system in regulating the intensity needed by the vehicle.
The designing of automotive lighting systems face some challenges. Main issues affecting the design of the drivers and their packaging include:
- The vehicle operates in a 12 Volt battery. This battery fluctuation ranges from six Volts up to 16 Volts in different operations. These fluctuations can be noted in different vehicle operations such as start, stop and battery charging.
- The driver should be designed to work over a wide temperature range. This temperature range generally varies from −40°C up to + 85°C.
- The LED driver should have a fault diagnostic system. This helps in quick fault detection in an automobile.
- The designed driver should meet EMI/EMC standard rules for electronic automotive appliances. These drivers generate noise signals which can interfere with nearby devices. These standards check the noise level of the devices and qualify them if the device is working in low-level noises.
These are some of the improvements which can be done for the development of automotive lighting solutions. Although LED’s have already been introduced in the automotive industry, there is still room for improvement in the development of LED drivers used in the vehicles.