90W Single stage PFC-flyback using L6562A for LED driver:In these years, power LEDs for lighting is quite hot application. For the reasons: theirlife of LED is significantly longer at 100,000 to 15,000 full-power hours (11+ years) tohalf brightness, the cost of power LEDs is rapidly coming down, and it’s easy to finddifferent sources from the market recently.We are always using the words to talk about LED lighting: high efficiency (light out perwatt in), long life… but if we look back to the power supply solution for LED lighting, it’shard to find the benefit of the long life. The E-caps using in the switching mode powersupply solution are limiting the total solution’s lifetime. And for several tens wattapplication, it’s hard to find suitable solution to meet the regulator requirement: PowerFactor or Harmonic Current requirement, but with low costing also.In this file, introduces the solution without E-cap, using traditional TM PFC controllorL6562A to control the flyback topology, combining the functions of PFC(Power Factorcorrection) and flyback topology (AC-DC converter), to meet the requirements: Longlifetime to match the LED Lighting’s feature, PF or Harmonic Current for regulator, andalso low costing for commerce. In this application, there are big advantages as talkedabove, but also a little drawback maybe somebody don’t like: double line frequency ripplevoltage on output, and also cause the same frequency ripple current on LEDs. It’s possibleto decrease the value of ripple voltage by adding e-caps at output side as adaptors, but it’simpossible to get the same small ripple voltage as adaptors do.