L99LD01 is a complete constant current DC-DC converter LED driver, manufactured in a BCD5S 70 V technology and assembled in a LQFP32TMpackage.
The device is designed to be used in boost, buck-boost and fly back converter topologies. An internal random dither oscillator works in low frequency modulation, allowing spreading the RF spectrum of the switching frequency, so reducing EMC emissions. The slope compensation ensures good converter loop stability whatever is the duty cycle needed by the application.
The converter is able to work either in full power mode or in low frequency dimming mode.
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.
**Key Features**
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 over voltage shut down 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)
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
Regulated output for micro supply 5 V ± 2 % - 20 mA
