Semtech Corporation SC4539
High Effi ciency Boost Converter
| Part No. | SC4539 |
|---|---|
| Datasheet | SC4539 Download |
| Manufacturer |  Semtech Corporation |
| Description | High Effi ciency Boost Converter |
| Buy | Stock & Price |
FEATURES
Input voltage range — 2.8V to 5.5V Current-mode PWM control — 800kHz Programmable LED current up to 30mA Soft-start to reduce in-rush current PWM dimming — 100Hz to 50kHz PWM dimming at ISET — Analog and filtered Over-voltage protection — 25V (max.) Under-voltage lockout (UVLO) Thermal shutdown Shutdown current — <1μA Ultra-thin package — 2mm x 2mm x 0.6mm Lead-free package, WEEE and RoHS compliant DESCRIPTION
The SC4539 is designed to regulate current for a series chain 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. An external resistor sets the LED current up to 30mA. PWM dimming (100Hz to 50kHz) may be applied directly to the enable (EN) pin, or dimming can be controlled by applying an analog signal to the ISET circuit. The boost circuit can output up to 22V (guaranteed) to drive up to 6 LEDs in series.
