ZXLD1320中文资料low-voltage-dc-dc-led-drivers数据手册Diodes规格书

描述 Description

The ZXLD1320 is an inductive DC-DC converter, with an internal switch, designed for driving single or multiple LEDs in series up to a total of 1.5A output current. Applications cover both commercial and automotive environments with input voltages ranging from 4V to 18V. Depending upon supply voltage and external components, this can provide up to 24W of output power. The device employs a variable 'on' and 'off' time control scheme with adjustable peak switch current limiting and operates in the step-down (Buck) operating mode, offering higher power efficiency and lower system cost than conventional PFM circuitry. The device includes the DC-DC converter, a high-side current monitor and an NPN switching transistor to provide an integrated solution offering small PCB size, competitive cost/performance, high power efficiency of DC-DC conversion and maximum LED brightness/reliability. More importantly, it retains design flexibility to add customer specific features. The feedback control circuitry inside the ZXLD1320 provides excellent load and current regulation, resulting in very stable LED current over the full operating voltage and temperature range. The LED current can be adjusted from 100% down to 10% of the set value by applying a dc voltage to the ADJ pin and down to 1% by applying a PWM signal. An on-chip LED protection circuit also allows output current to be reduced linearly above a predetermined threshold temperature using an external thermistor at the TADJ pin. External resistors set nominal average LED current and coil peak current independently. The 'Power-OK' (POK) output flag remains high during normal operation, but switches low if the switch transistor remains on for more than 500μs. This provides indication of a low battery, or fault condition. The POK output may be used to drive an LED or the input of an MCU. The device can be shut down by applying a continuous low level dc voltage to the ADJ pin.

特性 Features

Step-down LED driver
4V to 18V input voltage range
Up to 1.5A output current
Typical efficiency > 85%
User-defined thermal control of LED output current using external thermistor
High output current stability over input voltage and temperature
12μA typical standby current
LED current adjustable from 100% down to 2%
Adjustable soft-start
Power 'OK' flag output
Capable of driving 4 LEDs in series

应用 Application

Low voltage halogen lamp replacement with LEDs
High power LED flashlights
LED back-up lighting
General LED lighting
Automotive lighting

简介

ZXLD1320属于集成电路（IC）的LED驱动器。由制造生产的ZXLD1320LED 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。