Description

The SC4539 is designed to regulate current for a series string of white LEDs in LCD backlighting applications where small size and high efficiency are priorities. This device integrates an 800kHz current-mode PWM boost converter and a 30mA programmable low dropout current sink regulator.

Features

■ Input voltage range — 2.8V to 5.5V

■ Programmable LED current up to 30mA

■ Current-mode PWM control — 800kHz

■ Soft-start to reduce in-rush current

■ PWM dimming — 100Hz to 50kHz

■ PWM dimming at ISET — Analog and filtered

■ Over-voltage protection — 22V (minimum)

■ Under-voltage lockout (UVLO)

■ Thermal shutdown

■ Shutdown current — <0.1μA (typical)

■ Ultra-thin package — 2mm x 2mm x 0.6mm

■ Lead-free package, WEEE and RoHS compliant

Applications

■ DSLR, DSC, and Video Cameras

■ Cellular handsets

■ Portable media players

■ Personal navigation systems

■ Satellite radio

■ Handheld video games

SC4539屬于集成電路（IC） > LED 驅(qū)動器。Semtech Corporation制造生產(chǎn)的SC4539LED 驅(qū)動器器件屬于 LED 驅(qū)動器電源管理集成電路 (PMIC) 系列，可通過標(biāo)稱固定電壓的電源為負(fù)載（通常為發(fā)光二極管）提供電流，并且電流可控。它與用于電壓調(diào)節(jié)的類似產(chǎn)品的主要區(qū)別在于，這類器件提供較低的反饋電壓（以提高系統(tǒng)能效），而且通?？蓪ζ骷ぷ鼽c(diǎn)進(jìn)行外部控制，可在照明應(yīng)用中用于實(shí)現(xiàn)調(diào)光功能。