A8521KLPTR-T

• Product introduction

The A8521 is a multi-output white light for small LCD backlightsLED drivers。 It combines a current-mode boost converter with internal power switches and four sinks. The boost converter can drive up to 48 LEDs with 12 LEDs per string (80 mA per string). LED sinks can be paralleled to achieve higher LED currents up to 320 mA. The A8521 can operate from a single power supply from 5 V to 40 V, allowing the part to withstand load dump conditions that occur in automotive systems.

In the event of a fault, the A8521 can drive an external P-FET to disconnect the input power supply to the system. The A8521 provides a variety of protections, including output short-circuit and overvoltage, open- or short-circuit diodes, open- or short-circuit LED pins, short-circuit boost switches or inductors, short-circuit FSET or ISET resistors, and IC overtemperature protection. Two-stage wave-by-wave current limit provides soft-start and protection against high current overload in the internal current switch.

The A8521 has a sync pin that synchronizes the PWM switching frequency from 580kHz to 2.3 MHz. The high switching frequency allows the A8521 to operate above the AM radio band.

its with A8514 Much like that, the sink current that allows them to operate at very low PWM thresholds can be fine-tuned. This feature is sometimes required for applications such as head-up displays (HUDs).

The A8521 is available in a 20-pin TSSOP package (suffix LP) with an exposed heatsink mounted for enhanced thermal dissipation. It is packaged as lead (PB) free and is plated with 100% matte tin.

• AEC-Q100 compliant
• Wide input voltage range from 5 to 40 V for start/shutdown, cold crank and load dump requirements
• The LED sink and boost converters are fully integrated with the 60 V DMOS
• The sync function synchronizes the boost converter switching frequency up to 2.3 MHz and operates above the AM band
• Excellent input voltage transient response
• Single resistor first-stage overvoltage protection minimizes VOUT leakage
• Internal secondary overvoltage protection for redundancy protection
• The LED current per channel is 80 mA
• Drives up to 12 LEDs in series (4 series can be paralleled)
• 0.7% to 0.8% LED-to-LED matching accuracy
• PWM and analog dimming inputs
• Achieve 5000:1 PWM dimming at 200 Hz
• Provides a driver for the external PMOS input disconnect switch
• Extensive protection features:
  • Short-circuit boost switch or inductor
  • Short circuit the FSET or ISET resistor
  • Short-circuit output
  • Open or short LED pins
  • Open circuit boost Schottky protection
  • Overtemperature (OTP)