ALT80802: Wide Input Voltage, Adjustable Frequency, Buck-Boost or Buck 2 Amp LED Driver

ALT80802 Package Image


Top Features

The ALT80802 is a high-frequency switching regulator that provides constant output current to drive high-power LEDs. It integrates a power MOSFET for step-down or inverting buck boost conversion. The wide input range of 3.8 to 50 V makes the ALT80802 suitable for a wide range of lighting applications, including those in an automotive input environment. The device rating also enables a simple solution for driving 3 to 4 WLEDs in buck boost configuration—a very common application requirement for automotive lighting applications.

The ALT80802 is designed to aid in EMC/EMI design by frequency dithering, soft freewheel diode turn-off, and well controlled switch node slew rates. A programmable oscillator allows the ALT80802 to switch outside EMI-sensitive frequency bands such as the AM band.

With current-mode control and simple external compensation, the ALT80802 can achieve fast transient response. The control loop of the ALT80802 is designed for PWM dimming operation to achieve low dimming on-time and low turn-on overshoot. In buck-boost operation, the ALT80802 reduces the current overshoot normally caused by right half plane zero effect during a PWM diming turn-off transient. Extensive protection features of the ALT80802 include pulse-by pulse current limit, hiccup mode short-circuit protection, open/ short freewheeling diode protection, BOOT open/short voltage protection, VIN under voltage lockout, and thermal shutdown. Also, it includes internal clamp to prevent output voltage runaway if output LED string is opened in buck-boost operation.

The ALT80802 is available in a small 10 pin DFN package with thermal pad and wettable flank (automotive qualified).


  • AEC-Q100 qualified—Automotive-Grade; Facilitates system level certification
  • Simple operation—Same PN can be in buck-boost or buck mode
  • Supply voltage from 3.8 to 50 V
  • Handles automotive load dump and cold crank
  • Can be run in buck mode from a pre-boost supply
  • Supports up to 16 V output in buck-boost mode
  • Addresses automotive market need for 3-4 WLED solution
  • 150 mΩ integrated MOSFET switch
  • Supports up to ~2A in buck mode and ~750mA in buck-boost (Vinmin dependent)
  • Programmable switching frequency up to 2.5 MHz, with frequency dithering
  • Designed for low EMC
  • Operation can be above AM band
  • Small solution size
  • Integrated level shifting
  • Allows ground-referenced enable and fault flag in buck-boost mode
  • PWM dimming via direct logic input or power supply voltage
  • Supports all automotive PWM techniques including “single-wire”
  • Extensive protection and fault table
  • Robust, does not require extra protection components
  •  3x3mm DFN-10 wettable flank exposed pad package
  • Small yet thermally efficient
  • Wettable flank eliminates need for x-ray inspection

Part Number Specifications and Availability

Part Number Package Type Temperature RoHS
Part Composition /
RoHS Data
Comments Samples Check Stock
APEK80802KEJ-01-MH-BB DEMO BOARD -20°C to 85°C No -- Contact your
local sales rep
Distributor Stock
ALT80802KEJJTR 10-lead DFN -40°C to 125°C Yes View Data Contact your
local sales rep
Distributor Stock

Allegro’s products are not to be used in any devices or systems, including but not limited to life support devices or systems, in which a failure of Allegro’s product can reasonably be expected to cause bodily harm.


10 Lead QFN


Design Support Tools

ALT80802 Buck-Boost Design Tool (Excel)

ALT80802 Buck Design Tool (Excel)