lyt driver not working from square wave UPS

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    We have developed a tube light driver using LYT 4226e with the guidance of der338. Driver is absolutely fine with 230V line supply. But in the abscence of line power supply ,we use UPS( square wave) and the driver turns off. In place of C2 we use 4.7uF/450V.We tried other tube light drivers available in the market(india) and all are running smoothly with this square wave UPS. Kindly suggest a circuit modification to run the lyt driver from a square wave input.  awaiting your immediate reply





Unfortunately, LYT-4 is not designed to work with square wave input. The engine is meant to be used with sine input only. However, I remember it can work with DC input but affects the regulation. Is it possible that the unit is detecting a line OV condition with UPS input? Can you try to increase the RV (Vpin) resistor to confirm that it's not Line OV? If ever it works, the regulation could be significantly off.