LED driver controller for high-brightness strings
The Maxim Integrated MAX16834AUP+ is a DC DC controller designed for driving external N-channel MOSFETs in LED lighting applications. It supports both analog and PWM dimming, giving the designer control over brightness range and flicker-free operation. The controller can be configured in SEPIC, step-down (buck), or step-up (boost) topologies, covering a wide range of LED string voltages and current levels. Typical applications include automotive lighting (headlamps, daytime running lights, interior backlighting) and general backlight panels where the supply voltage can range from 4.75 V to 28 V.
Switching frequency and inductor sizing
The switching frequency is programmable from 100 kHz to 1 MHz, allowing the designer to optimize the inductor size and efficiency trade-off. At higher frequencies, the inductor shrinks — useful for space-constrained automotive modules — but switching losses increase. The 1 MHz upper end is typical for compact backlight drivers where board area is tight. The controller does not integrate the power switch (Internal Switch(s): No), so the external MOSFET and sense resistor must be selected for the peak LED current and thermal budget.
Temperature grade and automotive fit
Rated for -40°C to 125°C ambient, the MAX16834AUP+ is specified for automotive under-hood and cabin environments where thermal cycling and high ambient temperatures are routine. The 20-TSSOP-EP package with exposed pad helps conduct heat to the PCB ground plane, which is essential when driving high-current LEDs at elevated ambient temperatures. The 27 V output rating (Voltage - Output: 27 V) sets the ceiling for the LED string voltage; for higher-voltage strings, a boost topology with an external MOSFET rated above 27 V is needed.
Lifecycle and sourcing
ROHS3 compliant. For dual-sourcing or second-source evaluation, no direct pin-compatible alternate is listed in the official record; the designer should qualify the part for the BOM based on the topology and dimming requirements.