AAT1278中文资料1.5A Single Flash LED Driver数据手册Skyworks规格书

描述 Description

Please note: this product is being discontinued and is not recommended for new designs.

The AAT1278 is a high-efficiency, 1.5A high-current boost converter for LED photo flash applications. It maintains output current regulation by switching the internal high-side and low-side switch transistors, pulsewidth modulated at a fixed frequency of 2MHz. The high switching frequency allows the use of a small external inductor and output capacitor, making the AAT1278 ideally suited in all single cell, Li-ion-powered applications.

AnalogicTech’s proprietary AS2Cwire™ (Advanced Simple Serial Control™) serial digital interface is used to enable, disable, configure, and program the operation of the AAT1278. Using the AS2Cwire interface, the movie-mode current level for each LED, and the flash-to-movie-mode current ratio can be programmed to one of 16 levels. The AAT1278 includes a separate Flash Enable input to initiate the flash operation and a Flash Inhibit pin which reduces the flash current to movie-mode levels during high battery demand.

The maximum flash and movie-mode current is set by one external resistor where the ratio of flash to moviemode current is set at approximately 7.3:1. The AAT1278 can drive one high current LED. The AAT1278 contains a thermal management system to protect the device in the event of an output short-circuit condition. Built-in circuitry prevents excessive inrush current during start-up. The shutdown feature reduces quiescent current to less than 1.0μA.

The AAT1278 is available in a Pb-free, thermally-enhanced CSP-12 package and operates over the -40°C to 85°C temperature range.

Please note: AAT1278 is being discontinued and is not recommended for new designs.

特性 Features

• Input Voltage Range: 2.7V to 5.5V
• Single Channel Flash Output
• Up to 1.5A Regulated Output Current
• Up to 88% Efficiency
• 2 MHz Switching Frequency
• Separate Flash Enable
• Single Resistor Sets Flash and Movie Mode Current
• AS2Cwire Single Wire Programming:
• Movie Mode Current
• Flash/Movie Mode Current Ratio
• True Load Disconnect
• Soft-Start and Input Current Limit
• Over-Voltage (Open LED, Open Circuit), Short Circuit,and Over-Temperature Protection
• -40°C to +85°C Temperature Range

简介

AAT1278属于集成电路（IC）的LED驱动器。由制造生产的AAT1278LED 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。