A8519KETTR-R

• Product Introduction

The A8519 is a multi-output LED driver for small LCD backlighting. It integrates a current-mode boost converter with an internal power switch and four current absorbers. The boost converter can drive up to 44 white LEDs, 11 LEDs per string of 100 mA current. LED current absorbers can be connected in parallel to achieve higher LED currents up to 400 mA. The A8519 operates from a single supply from 4.5 V to 40 V, allowing the component to withstand load dumps that occur in automotive systems.

The A8519 controls the brightness of the LEDs via a digital (PWM) signal. By PWM dimming at 100 Hz, a 10,000:1 LED brightness contrast ratio 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 system's input power in the event of a failure. The A8519 provides protection including output short-circuit and over-voltage protection, secondary open-circuit or short-circuit protection, LED pin open-circuit or short-circuit protection, and over-temperature protection. Cycle-by-cycle current limiting prevents high current overloads on the internal boost switch.

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

• 符合汽车行业 AEC-Q100 标准
• 适用于升压转换器的完全整合型 42 V MOSFET
• 完全整合的 LED 电流吸收器
• 可承受高达 40 VIN 的浪涌输入，以应对负载突降情况
• 可在降至 3.9 VIN（最高）的电压下运行以便进行怠速停止
• 可驱动四串 LED
• 最大输出电压为 40 V
  • 多达 11 个白光 LED 串连在一起
• 每串的驱动电流为 100 mA
• 可编程的升压开关频率（400 kHz 至 2.15 MHz）
• 同步的升压开关频率选择（300 kHz 至 2.3 MHz）
• 抖动升压开关频率以降低 EMI
• 非常高的 LED 亮度对比率
  • 仅使用 PWM 调光时为 10,000:1
  • 将 PWM 和模拟调光结合在一起使用时为 100,000:1
• 在 PWM 占空比最低的情况下具有出色的输入电压瞬态响应性能
• 适用于可选 P 通道 MOSFET 输入断开开关的门驱动器
• LED 电流精度为 0.7%
• LED 串电流匹配精度为 0.8%
• 提供以下保护：
  • ƒƒ升压开关、电感器或输出电容器短路保护
  • FSET 或 ISET 电阻器短路保护
  • LED 引脚和 LED 串开路或短路保护
  • 升压二极管开路保护
  • 过热保护