Prediction of future development trend of automotive ambient lighting

The future development of ambient lighting will become more and more intelligent and humanized. High-quality automotive ambient lighting has become an indispensable design element in the field of automotive interiors. This article introduces a series of RGB ambient lighting driver chip solutions brought to us by Lumissi.

Things develop from simple to complex, from single to diversified, and so does the atmosphere light. From the commonly used single-color uncontrollable atmosphere light, it has developed into the current multi-color controllable atmosphere light; from simple uncontrollable static light to color stillness/breathing, music/speed rhythm, etc., you can choose dimming, color change, dynamic and static switching, rhythmic rhythm frequency change and other functions through the control panel.

Currently, most LIN RGB driver chips on the market can only drive a single RGB LED. If some location atmosphere lights need to drive multiple RGB lights, multiple LIN RGB LED driver chips will be needed, which will greatly increase the cost of the entire system.

For such applications, Lumissil Microsystems (a sub-brand of ISSI analog mixed signal) recently released a number of in-car ambient lighting driver chips that meet the stringent AEC-Q100 automotive grade standards.

 IS32FL3265A/B: 18-way constant current driver chip with output that can withstand 40V high voltage

 IS32FL3237/3240/3238/3236A/3209: 36/30/18-channel constant current driver IC at 5V

This series of chips can achieve perfect and precise control of the brightness and color of each LED, and is particularly suitable for applications with multiple ambient lights in a local area, such as driving instrument panel indicator lights, car air-conditioning panel ambient lights, various cockpit and door ambient lights, through-type flowing welcome lights/tail lights, and other applications.

Lumissil drives a multi-channel RGB atmosphere light system. The system uses the automotive-grade high-voltage 3A Buck constant-voltage driver chip IS32PM3420 to provide a 5V power supply voltage, and uses the automotive-grade MCU IS32CS89xx to control various lighting effect LED driver chips to drive multiple RGBLEDs (up to 12 or 6 RGBs), thereby greatly reducing the overall system cost and only occupying one LIN address.

IS32FL3265A/B 18-channel high-voltage constant-current LED driver chip

The output withstand voltage can reach 40V, and the maximum output current of a single channel can reach 60mA

 Communication interface: I2C (A) or SPI (B),

Supports 8-bit PWM (200Hz or 25kHz) dimming for each channel, global 5-bit current and single-channel 8-bit DC current white balance adjustment function.

The chip integrates advanced output phase control (Output Phase delay) and clock spread spectrum (Spread Spectrum) functions, which greatly reduces power supply ripple/capacitor high-frequency noise and reduces EMI interference.

The chip supports online real-time LED open circuit fault detection and error reporting, over-temperature current reduction, over-temperature shutdown protection and other protection functions.

IS32FL3237/3240/38 ----36/30/18-channel 5V constant current LED lighting driver chip

The maximum output current of each channel can reach 38mA/76mA

 Communication interface: I2C

It supports up to 16-bit PWM dimming per channel and 8-bit global current and 8-bit single-channel DC current white balance adjustment functions, which can perfectly and accurately mix any RGB color and perform delicate white balance adjustment.

 The frequency of PWM output is adjustable, up to 62KHz, which can eliminate the high-frequency sound of the capacitor.

The chip integrates advanced output phase control (Output Phase delay) and clock spread spectrum (Spread Spectrum) functions, which greatly reduces power supply ripple/capacitor high-frequency noise and reduces EMI interference.

The chip supports online real-time LED open circuit fault detection and error reporting, over-temperature current reduction, over-temperature shutdown protection and other protection functions.

The above multi-channel LED driver chips can operate at temperatures from -40°C to +125°C and have passed the rigorous automotive grade AEC-Q100 standard test. All products are now in mass production.

In the future, cars will become the second intimate private space outside of home. Car interior lighting has become a design element that cannot be ignored. Ambient lighting is in the market introduction and growth stage. Let’s discuss together how to design ambient lighting better and perfectly realize the interaction between people and cars. Let’s wait and see!