SANKEN LC5546LF

The LC5540LF series is the power IC for the isolated type LED driver which has an incorporated power MOSFET, designed for input capacitorless applications, and making it possible for systems to comply with the harmonics standard (IEC61000-3-2 class C), even during light load condition. The controller adapts the average current control method for realizing high power factors, and the quasi-resonant topology contributes to high efficiency and low EMI noise. The series is housed in TO-220 packages. The rich set of protection features helps to realize low component counts, and high performance-to-cost power supply. The incorporated MOSFET has a VDSS(min) rating from 650 V (LC5546LF and LC5547LF) to 800 V (LC5549LF). The RDS(on)(max) is 1.1 Ω (LC5547LF) to 1.9 Ω (LC5546LF). It is capable of a maximum output power of 80 W on 230\VAC supply to 55 W on universal input supply (85 to 265VAC) (LC5547LF) based on the thermal rating. Note that the maximum output power can be up to 120% to 140% of this value. However, it may be limited in applications with low output voltage or short duty cycle.

• Integrated on-time control circuit (it realizes high power factor by average current control)
• Integrated startup circuit (no external startup circuit necessary)
• 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

• LED lighting fixtures
• LED light bulbs