STMicroelectronics L99LD High-Efficiency Constant Current LED Driver

STMicroelectronics L99LD High-Efficiency Constant Current LED Driver is a complete constant current DC-DC converter LED driver for automotive applications. STMicroelectronics L99LD is manufactured with BCD5S 70V technology and assembled in a LQFP32 package. The L99LD is designed to be used in Boost, Buck-Boost and Fly back converter topologies.

The device includes an internal low drop voltage regulator, that can be used to supply a microcontroller, and a reset pin, that is useful for resetting the microcontroller at the start up and every time that the regulated output voltage falls down below an established voltage threshold.

Features

Automotive qualified
Constant current operation
Current LED settable by external sensing resistor and adjustable via SPI
Converter switching frequency adjustable by external resistor (RSF)
EMC reduction by internal spread spectrum dither oscillator
Low frequency PWM dimming operation
Maximum input current limiter
Maximum switching duty cycle limiter
Slope compensation adjustable by external resistor (R9)
Battery overvoltage shutdown protection (ext. R3, R4 resistors required)
LED chain OV detection (ext. R5, R6)

Multiplexed output for monitoring and control of LED temperature (external NTC resistor required), voltage of LED chain, and low frequency PWM
SPI communication serial interface transceiver (SDI, SDO, SCK, CSN)
Regulated output for micro supply 5V ±2% -20mA
Parameter programming and settings of internal memory registers by the dedicated SPI interface:
LED current reference adjusting (±66.7%)
Maximum input current limiter reference adjusting (±55.5%)
Random dither frequency sweeping, modulation frequency and deviation percentage
Power on reset pin output
ESD protection