A8512中文资料LED Backlight Driver for LCD Monitors and Televisions数据手册Allegro规格书

描述 Description

This device is in production, however, it has been deemed Pre-End of Life. The product is approaching end of life. Within a minimum of 6 months, the device will enter its final, Last Time Buy, order phase. Date of status change: December 5, 2018.

Recommended Substitutions: ALT80600.

The A8512 is a multi-output WLED/RGB driver for backlighting LCD monitors and televisions. It integrates a boost controller to drive external MOSFET, and six internal current-sinks. The boost converter operates in constant frequency (programmable) current mode control.

PWM dimming allows LED currents to be controlled in 500:1 ratio. The LED sink current is set by an external R_ISET resistor (see chart at right). More than one LED sinks can be combined together to achieve even higher current per LED string. Multiple A8512s can be connected in parallel, with one master controller controlling the boost stage, and up to five slave controllers, which act as LED sinks. This allows up to 36 LED strings to be powered by just one boost converter.

The A8512 operates from a single supply of 8 to 24 V. It provides protection against overvoltage, open or shorted LED string, and overtemperature. A dual level cycle-by-cycle current limit function provides soft start and protects against overloads.

The device is provided in a 24-pin SOICW package (LB), with internally fused pins for enhanced thermal dissipation, and a 28-contact 5 mm × 5 mm QFN package (ET) and a 24-pin TSSOP package (LP), both with an exposed thermal pad for enhanced thermal dissipation. All packages are lead (Pb) free, with 100% matte tin leadframe plating.

特性 Features

• Six integrated high current sinks
• Fixed frequency current mode control with integrated gate driver
• 300 kHz to 1 MHz adjustable switching frequency
• Controlled startup using options of Enable, PWM signal, or battery voltage ramp
• Parallel operation with one boost controller (master) and up to five slave controllers
• Active current sharing between LED strings for ±0.6% accuracy and matching
• No audible MLCC noise during PWM dimming
• Adjustable overvoltage protection (OVP)
• Open or shorted LED string protection
• Overtemperature, cycle-by-cycle current limit, and undervoltage protection
• SOIC 24-pin package for easy single-side PCB manufacturing, or TSSOP 24-pin and QFN 28-contact packages with exposed thermal pad for better thermal performance

简介

A8512属于集成电路（IC）的LED驱动器。由制造生产的A8512LED 驱动器器件属于 LED 驱动器电源管理集成电路 (PMIC) 系列，可通过标称固定电压的电源为负载（通常为发光二极管）提供电流，并且电流可控。它与用于电压调节的类似产品的主要区别在于，这类器件提供较低的反馈电压（以提高系统能效），而且通常可对器件工作点进行外部控制，可在照明应用中用于实现调光功能。