What the MAX16821BATI+ actually does
The MAX16821BATI+ from Maxim Integrated is a DC DC controller IC designed specifically for LED backlighting applications. It is a controller, not a converter with integrated switches — meaning you supply the external MOSFET and inductor, and the chip handles the PWM dimming and regulation loop. The part supports three topologies — SEPIC, step-down (buck), and step-up (boost) — which gives a single BOM line the flexibility to drive LED strings in series or parallel depending on the input rail and output voltage needed. The switching frequency is programmable from 125 kHz to 1.5 MHz, letting you trade inductor size and switching losses against each other. A higher frequency shrinks the magnetics but increases FET gate-drive loss; a lower frequency improves efficiency at the cost of a larger inductor. The single output drives an external N-channel MOSFET, and the PWM dimming input allows direct LED brightness control without an external DAC or microcontroller PWM pin. The supply voltage range spans 4.75 V to 28 V. The operating temperature range is -40°C to 125°C.
Lifecycle and sourcing reality
The MAX16821BATI+ carries an active lifecycle status with ROHS3 compliance. No stock or lead-time number is published here because the spot market moves daily; a quick RFQ will return the real picture.