LC5555LD

LC5550LD Series Single-Stage Power Factor Corrected High Efficiency Non-Isolated Buck LED Driver Features and Benefits PWM and quasi-resonant topology Integrated on-time control circuit (it realizes high power factor by average current control) Integrated soft-start circuit (reduces power stress during start-up on the incorporated power MOSFET and output rectifier) Integrated bias assist circuit (improves startup performance, suppresses VCC voltage droop during operation, and allows use of low-rated ceramic capacitor on VCC pin) Integrated Leading Edge Blanking (LEB) circuit Integrated maximum on-time limit circuit Protection features: ▫ Overcurrent protection (OCP): pulse-by-pulse ▫ Overvoltage protection (OVP): latched shutdown ▫ Overload protection (OLP): latched shutdown ▫ Thermal shutdown (TSD): latched shutdown Package: 8-pin DIP Description LC5550LD series are PWM and quasi-resonant topology non-isolated buck LED driver ICs. They incorporate separate controller and power MOSFET chips, and are designed for input capacitorless applications. The controller adapts the average current control method for realizing high power factors. The rich set of protection features helps to realize low component counts, and high performance-to-cost power supply. Applications LED lighting fixtures LED light bulbs Not to scale Typical Application R1 D6 R2 U1 NF 5 LC5550LD COMP 4 3 OCP/BD 2 1 V CC S/GND R5 Contro1 6 ISENSE D3 V AC D1 D2 D4 D/ST 8 C2 C3 C4 C5 C...