12-channel boost LED driver with digital dimming
The LP55281TL/NOPB is a 12-output DC-DC boost regulator LED driver from Texas Instruments, designed for backlight applications. Each channel delivers up to 40 mA, with the output voltage adjustable between 4 V and 5.3 V via the integrated boost converter. Dimming is controlled through I²C or SPI interfaces, giving the firmware direct command over individual channel brightness without external PWM generators. The 2 MHz switching frequency keeps the inductor and capacitor small, shrinking the PCB footprint for space-constrained backlight panels.
Output count and current — sizing the LED string
Twelve independent current sinks, each rated 40 mA, sum to a total drive capability of 480 mA. The boost converter's internal switch handles the combined load, so no external FET is needed for the power stage. The output voltage compliance range (4 V to 5.3 V) suits series strings of two to three white LEDs per channel, depending on forward voltage. Operating temperature spans -30°C to 85°C, covering indoor and most outdoor-rated backlight enclosures.