HV9919B中文资料Hysteretic, Buck, High Brightness LED Driver w/ High-Side Current Sensing数据手册Microchip规格书

描述 Description

The HV9919B is a PWM controller IC designed to drive high brightness LEDs using a buck topology. It operates from an input voltage of 4.5 to 40VDC and employs hysteretic controlwith a high-side current sense resistor to set the constant output current.The operating frequency range can be set by selecting the proper inductor. Operation at high switching frequency is possible since the hysteretic control maintains accuracy even at high frequencies. This permits the use of small inductors and capacitors minimizing space and cost in the overall system.LED brightness control is achieved with PWM dimming from an analog or PWM input signal. Unique PWM circuitry allows true constant color with a high dimming range. The dimming frequency is programmed using a single external capacitor.The HV9919B comes in a small, 8-Lead DFN package and is ideal for industrial and general lighting applications.

特性 Features

• Hysteretic control with high-side current sensing
• Wide input voltage range: 4.5 to 40V
• >90% Efficiency
• Typical ±5% LED current accuracy
• Up to 2.0MHz switching frequency
• Adjustable constant LED current
• Analog or PWM control signal for PWM dimming
• Over-temperature protection
• -40ºC to +125ºC operating temperature range

简介

HV9919B属于集成电路（IC）的LED驱动器。由制造生产的HV9919BLED 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。