110V LED T9 Tube HT7L4091 Electrolytic Capacitor Free Characteristics AC 100V ~ 120V input Electrolytic capacitor free Long life Easy design for thermal dissipation Low cost Optional high power factor with low cost design 8S20P 10W LED Simple current-mode buck structure Low start-up current for flexible design to power the HT7L4091 IC over temperature protection Shut down function for serious LED short circuits -- all LEDs are shorted Adaptive voltage for partial LED short circuit - partial LEDs are shorted Inherent LED open circuit protection LED Optional Protection Circuit Optional EMC Circuit HT7L4091 Rectifier Operating Procedure Insert the plug into an AC power socket Buck Circuit Optional Output Capacitor Application Circuit MOV Application Options This design can be adjusted for different application requirements. Efficiency improvement Using the HT7L4091 with higher efficiency design : Buck inductor auxiliary winding : Higher performance Simple linear regulator using BJT + diode : provides power to the other components using the LDO of the HT7L4091 Voltage divider using reactive impedance (capacitor) : On-the-shelf components and low heat generation Full range AC input Remove input voltage sense for power factor improvement Efficiency improvement solutions may be used Intelligent lamps Combine with Holtek’s solutions PIR controller TinyPowerTM MCU Remote controller Power above components using the 5V LDO of the HT7L4091 Linear regulator using BJT + diode may be used