Auto-grade buck regulator drives LEDs
Article By : Allegro
The A6217 LED driver, made with N-channel DMOS switch for DC-to-DC buck conversion, caters to a variety of automotive lighting applications.
Allegro has unveiled the A6217 single IC switching regulator designed to drive current output to LEDs especially in automotive applications.
The A6217 utilises an N-channel DMOS switch for DC-to-DC step-down (buck) conversion. True average current uses a cycle-by-cycle, controlled ontime method.
This LED driver can be used in automotive applications, such as daytime running lights, front and rear fog lights, turn/stop lights, map lights, and dimmable interior lights.
The output current is user-selectable via an external current sense resistor. Output voltage is adjusted automatically to control multiple LEDs in a single string. LED dimming can be accomplished by using "chopped battery" PWM or analogue dimming capability. The A6217 also uses switching frequency dithering for reduced EMI signature.
The A6217, successor of the A6213 LED driver, is available in a pinout-equivalent eSOIC-8 package (LJ) or a 3mm x 3mm wettable flank DFN-10 (EJ). Either package has an exposed pad for thermal dissipation and is lead-free with matte-tin leadframe plating.
