MIC3291数据手册集成电路（IC）的LED驱动器规格书PDF

描述 Description

The MIC3291 is a PWM switching boost regulator that is optimized for constant current white LED (WLED) driver applications. The MIC3291 features an internal Schottky diode, allowing an efficient DC/DC solution that requires only four external components.The MIC3291 allows for a single-wire simple digital interface to control the dimming over 16 steps with a linear scale. The preprogramming feature allows the user to select any one of the 16 WLED current levels as the start up brightness level.The feedback voltage of the MIC3291 is only 250mV, allowing high efficiency while retaining excellent accuracy for the WLED current.The MIC3291 implements a constant frequency 1.2MHz PWM control scheme. The high frequency PWM operation saves board space by reducing external component sizes. The 1.2MHz PWM scheme also reduces switching noise and ripple to the input power source.The 2.5V to 6.5V input voltage range of the MIC3291 allows direct operation from single cell Li-Ion as well as 3- to 4-cell NiCad/NiMH/Alkaline batteries. Battery life is preserved with a low 1µA shutdown current.The MIC3291 is available in a low profile Thin SOT23 6-pin and 2mm x 2mm MLF® 8-pin packages with a junction temperature range of -40°C to +125°C.

特性 Features

• Single wire combines 16 level linear brightness and shutdown control
• 18V/25V OVP options supports up to four and six WLEDs
• Startup in any one of 16 brightness levels
• Internal Schottky diode
• 2.5V to 6.5V input voltage
• 1.2MHz PWM operation
• Over 500mA switch current
• 250mV reference voltage
• ±5% LED current accuracy
• <1µA shutdown current
• UVLO and over-temperature protection
• Thin SOT23-6L package option
• 2mm x 2mm leadless MLF®package option
• -40°C to +125 °C junction temperature range

简介

MIC3291属于集成电路（IC）的LED驱动器。由制造生产的MIC3291LED 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。