AT9917数据手册集成电路（IC）的LED驱动器规格书PDF

描述 Description

The AT9917 is an advanced fixed frequency PWM IC designed to control single-switch, boost, SEPIC, and buck LED drivers in a constant current mode. The controller uses a peak current-mode control scheme (with programmable slope compensation) and includes an internal transconductance amplifier to control the output current with high accuracy. The IC includes a +/-1A gate driver that makes the AT9917 suitable for high power applications. An internal 40V linear regulator powers the IC eliminating the need for a separate power supply for the IC. The IC provides a FAULT output, which can be used to disconnect the LEDs in case of a fault condition (such as an alternator load dump in automobiles) using an external disconnect FET. AT9917 also provides a TTL compatible, low-frequency PWM dimming input that can accept an external control signal with a duty ratio of 0-100% and a frequency of up to several kilohertz. Temperature foldback of the output current is possible, using an external NTC resistor.The AT9917-based LED driver is suited for automotive LED driver applications. The AT9917 based LED lamp drivers can achieve efficiencies in excess of 90% when buck or boost topologies are used.

特性 Features

Switch mode controller for boost, SEPIC & buck converters
Closed loop control of output current
High PWM dimming ratio
Internal 40V linear regulator
Internal 3% voltage reference
Constant frequency operation with programmable slope compensation
Linear and PWM dimming
Programmable jitter to reduce EMI
+/-1.0A MOSFET gate driver
Output short circuit protection
Output over voltage protection
Programmable hiccup timer
Temperature fold-back with external NTC resistor
Soft start
Meets AEC-Q100 requirements

简介

AT9917属于集成电路（IC）的LED驱动器。由制造生产的AT9917LED 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。