Stmicroelectronics CAN FD Light multi-pixel drive to help design the next generation of automotive lighting

     Stmicro's L99LDLH32 linear current stabilizer provides a simple integrated solution for controlling dynamic automotive lighting using the lightweight CAN FD Light protocol. The new drive is a perfect match for OLED lights, which emit bright, uniform and high-contrast light from a small surface, allowing designers to create complex patterns and light effects that enhance vehicle safety and exterior design visuals.

    The L99LDLH32 has 32 independently programmed steady current power supplies in the 1mA to 15mA range, which can individually drive each pixel of the light fixtures inside and outside the car, and also provides overall dimming with 8-bit resolution. When powered by vehicle battery voltage, the maximum output voltage of the driver is 35 V, covering a wide emitter forward voltage range.

     The on-chip integrated CAN FD Light protocol processor and transceiver simplify the connection of the streamer chip to the vehicle communication infrastructure and the ECU in the control domain. CAN FD Light's controller/transponder synchronous communication is based on established industry standards and is used to control simple devices such as lamps and sensors, saving costly external components such as timing crystals. On the other hand, the 1Mbit/s data bandwidth allows designers to create complex animated patterns, achieve modulated smooth transitions between light and dark and dimming effects.

     In addition, the on-chip storage unit allows setting of independently working current intensity and PWM dimming parameters to provide system failure protection in the event of a functional failure of the communication bus or controller. Targeted applications for the L99LDLH32 include safety-critical lighting such as taillights, brake lights, and turn signals, providing the features needed to achieve high functional safety, including fail-state pins, voltage monitors, temperature monitors, programmable timeout watchdogs, and short - and open-circuit load detection. In addition, frequency jitter technology minimizes electromagnetic radiation.