APM80904 Datasheet | Allegro MicroSystems

FEATURES AND BENEFITS - Automotive AEC-Q100 qualified - Supply voltage 4.5 to 36 V, maximum 40 V - plete 1.5 A output pact LED driver - Integrated inductor, VIN and boot capacitors - Ultra-low EMI architecture, f SW > 2 MHz - Spread spectrum for improved EMC - Integrated high-side and low-side MOSFETs: 80 mΩ / 60 mΩTYP , 90% efficiency at 1 A - 5 V, 14 m A LDO regulator for peripheral circuits - Dimming via external PWM or EN pin - Programmable internal PWM dimming - Analog dimming for brightness calibration and thermal foldback - Low power shutdown (1 μA typical) - High side current sense, ±3% accuracy - Fault flag output - LED open fault mask setting for low VIN operation - Undervoltage lockout (UVLO) and thermal shutdown protection - Robust protection against: - Adjacent pin-to-pin short - Pin-to-ground short - ponent open/short faults PACKAGE: Not to scale 32-pin QFN 4 mm × 6 mm × 2.1 mm with wettable flank (suffix NB) DESCRIPTION The APM80904 is a plete synchronous buck switching regulator module that provides constant current output to drive high-power LEDs. It integrates both high-side and low-side N-channel switches, inductor, high frequency VIN and boot capacitors. A true average current is output using a cycle-bycycle, controlled on-time method. Output current is user-selectable by an external current sense resistor. Output voltage automatically adjusts to the LED string voltage to ensure optimal system efficiency. LED dimming is acplished by a direct logic input pulsewidth modulation (PWM) signal at the PWM pin while EN is enabled. Alternatively, applying a PWM signal at the EN pin while the PWM pin is high provides “chopped battery” PWM dimming for legacy control modules. Additionally, the APM80904 includes programmable internal dimming. The analog dimming input (ADIM pin) can be used to calibrate the LED current or implement thermal foldback in conjunction with an external NTC thermistor. The APM80904 is provided in a pact, thermally enhanced 4 mm × 6...