The A8517 is a programmable multi-output LED driver for a wide range of LED driver applications. The driver incorporates a current-type boost regulator with a built-in power switch and 10 current absorbers. The ICs operate from 4.5 to 36 volts and can withstand load dumps of up to 40 volts that occur in automotive systems.
The I2C interface allows users to set the LED current individually, up to 60 mA per LED channel. Adjacent channels can be combined to drive higher current LED strings. The PWM dimming duty cycle can be controlled individually for each LED channel, and individual channels can be enabled/disabled independently if needed.
This flexibility makes the A8517 a single solution for a variety of LED applications, i.e., in some cases, replacing two or more LED driver ICs with one device.
The optimized control loop enables extremely high dimming ratios using only PWM controls, smoothly responds to supply voltage transients and step changes, and eliminates night flickering when display backlight applications are started with a very low PWM duty cycle.
The A8517 detects and prevents various fault conditions and reports fault status via dual communication. It features output short-circuit and over-voltage protection, open-circuit or short-circuit secondary tube protection, open-circuit or short-circuit LED pin protection, short-circuit boost switch or inductor protection, and IC over-temperature protection. Dual cycle-by-cycle current limiting prevents switching overcurrent on the built-in switch. If required, the IC can drive an external PFET that acts as an input disconnect switch, which is triggered by an integrated current sensor.
应用：
Car:
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资讯娱乐
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群集
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车辆中控面板照明
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抬头显示器 (HUD)
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白天行驶灯 (DRL)
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经 AEC Q100 验证的 4.5 到 36 伏宽输入电压范围
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可承受低至 3.9 伏（VIN 下降）的怠速停止和高达 40 伏的甩负荷
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整合带 DMOS 开关的升压稳压器，过压保护高达 39 V
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10 个完全整合的电流吸收器，每通道的电流可单独编程达 60 mA
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I2C™ 接口，用于编程 LED 电流、PWM 调光和每通道的各个保护阈值
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使用单个 IC 驱动多个负荷
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宽广的 PWM 调光范围（在 100 Hz 时高达 10,000:1），可为每个通道单独编程
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广泛的诊断和故障报告
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在较高温度时发出热警告和使 LED 电流降额
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针对所有通道的缓冲 PWM 调光控制，以促进局部调光应用
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多相 PWM 调光：参差调谐的 LED 电流，以降低闪光和输入纹波电流
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同步升压开关频率：400 kHz 至 2.3 MHz，允许低于或高于 AM 段工作
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可编程频率抖动以降低 EMI
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典型 LED 电流准确率为 0.7%，LED 至 LED 匹配准确率为 0.8%。
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保护功能
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开路/短路 LED 引脚检测
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可编程 LED 串短路检测
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开路/短路外部组件（包括升压电感、肖特基二极管、FSET 电阻器等）
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预防输出至 GND 短路的输入过流保护
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逐周期开关电流限制
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过温、输出过压和欠压保护