The A8502 is a multi-output white LED driver for small LCD backlighting. It integrates a current-mode boost converter with an internal power switch and two current converters. The boost converter can drive up to 24 LEDs of 12 LEDs per string (120 mA per string). LED sink currents can be paralleled to achieve higher LED currents up to 240 mA. The A8502 operates from a single supply from 5 V to 40 V, allowing the component to withstand load dumps in automotive systems.
In the event of a failure, the A8502 can drive an external P-FET to disconnect the system's input power. The A8502 offers a variety of protections, including output short-circuit and overvoltage, open-circuit or short-circuit diodes, open-circuit or short-circuit LED pins, short-circuit boost switches or inductors, short-circuit FSET or ISET resistors, and IC over-temperature protection. The two-stage wave-by-wave current limiting feature provides soft start and protection against high current overloads in the internal current switch.
The A8502 can synchronize PWM switching frequencies from 580kHz to 2.3MHz via the sync pin. The high switching frequency allows the A8502 to operate above the AM radio band.
The A8502 is available in a 16-pin TSSOP package (suffix LP) and is fitted with an exposed heatsink for improved thermal functionality. They are all lead-free and 100% matte tin plated.
apply
LCD backlight or LED lighting is used for:
-
汽车娱乐资讯
-
汽车蓄电池组
-
汽车中控台
-
-
5 至 40 伏特宽输入电压范围，可满足启动/关闭、冷车启动和负载突降要求
-
LED 灌电流和升压转换器与 60 伏特 DMOS 完全整合
-
同步功能可同步高达 2.3 MHz 的升压转换器开关频率，可在 AM 波段以上运行
-
出色的输入电压瞬态响应
-
单电阻器主级过电压保护最大程度减少 VOUT 泄漏
-
用于冗余保护的内部次级过电压保护
-
每通道 120 mA 的 LED 电流
-
驱动多达 12 个串联 LED（分为 2 个并联的串）
-
0.7% 至 0.8% 的 LED 至 LED 匹配准确度
-
PWM 和模拟调光输入
-
为可选的外部 PMOS 输入断开开关提供驱动器
-
广泛的保护功能：
-
短路升压开关或电感器保护
-
短路 FSET 或 ISET 电阻器保护
-
短路输出保护
-
开路或短路 LED 引脚保护
-
开路升压肖特基保护
-
过温保护 (OTP)