A8519KETTR-R

• Product introduction

A8519is a multi-output for small LCD backlightingLED drivers。 It integrates a current-mode boost converter with an internal power switch and four current sinks. The boost converter can drive up to 44 white LEDs with 11 LEDs per string at 100 mA each. LED current sinks can be paralleled to achieve higher LED currents up to 400 mA. The A8519 can operate from a single supply from 4.5 V to 40 V, allowing the part to withstand load dumps in automotive systems.

The A8519 controls the brightness of LEDs through digital (PWM) signals. With PWM dimming at 100 Hz, a 10,000:1 contrast ratio of LED brightness can be achieved. If PWM and analog dimming are used together, it is possible to achieve a higher ratio of 100,000:1.

If needed, the A8519 can drive an external P-channel MOSFET to disconnect the input power to the system in the event of a fault. Protection provided by the A8519 includes output short-circuit and overvoltage protection, open- or short-circuit protection of diodes, open- or short-circuit protection of LED pins, and overtemperature protection. Cycle-by-cycle current limiting prevents high current overload in the internal boost switch.

The A8519 has a synchronization pin that synchronizes the boost switching frequency from 300 kHz to 2.3 MHz. The high switching frequency allows the converter to operate above the AM radio band. The IC contains a clock output pin that allows other converters to synchronize with the boost switching frequency of the A8519'.

• Automotive AEC-Q100 compliant
• Fully integrated 42 V MOSFETs for boost converters
• Fully integrated LED current sink
• Withstands surge inputs up to 40 VIN to handle load dumps
• Can operate down to 3.9 VIN (max) for start-stop
• Drives four strings of LEDs
• The maximum output voltage is 40 V
  • Up to 11 white LEDs are connected in series
• The drive current per string is 100 mA
• Programmable boost switching frequency (400 kHz to 2.15 MHz)
• Synchronous boost switching frequency selection (300 kHz to 2.3 MHz)
• Jitter boost switching frequency to reduce EMI
• Very high contrast ratio of LED brightness
  • 10,000:1 with PWM dimming only
  • 100,000:1 when PWM and analog dimming are combined
• Excellent input voltage transient response with the lowest PWM duty cycle
• Gate driver for optional P-channel MOSFET input disconnect switch
• LED current accuracy of 0.7%
• LED string current matching accuracy of 0.8%
• Provides the following protections:
  • Boost switch, inductor, or output capacitor short-circuit protection
  • FSET or ISET resistor short-circuit protection
  • LED pins and LEDs are protected against open or short circuits
  • Boost diode open circuit protection
  • Overtemperature protection