Any available units are from existing stock, not new manufacture. RoHS non-compliant — verify the BOM's environmental compliance requirements before committing. This part does not carry a current RoHS exemption.
Boost LED driver with dual 44V outputs
The LM3503SQ-44 is a DC-DC boost regulator designed for backlight applications. It integrates two switch outputs each rated for 750 mA switch current, allowing independent control of two LED strings. Output voltage reaches 44V, which supports driving multiple series-connected LEDs per channel — typical for medium-size LCD backlight panels. Dimming is supported via both Analog and PWM methods, giving the designer flexibility in brightness control and EMI management.
Supply range and package fit
Operates from a supply voltage of 2.5V to 5.5V, covering single-cell Li-Ion and 3.3V/5V rails. Housed in a 16-WFQFN Exposed Pad package, supplier device package 16-WQFN (4x4 mm).
Second-source and replacement options
The closest functional sibling is the LM3500TL-16, a single-output boost driver with 0.4 A switch current and the same 1 MHz frequency and backlight application. It is not a direct pin-for-pin replacement — the package and output count differ. The LM3508TL/NOPB is a lower-current (0.03 A) single-output PWM-dimming boost driver with 850 kHz switching.