KP1071LSPA is a highly integrated power switch with Quasi-Resonant Buck (QR-Buck) constant current (CC) control for LED lighting applications without auxiliary winding.KP1071LSPA combines a 500V power MOSFET, 600V FRD, 800V Rectifier Bridge and high voltage startup/IC supply circuit in one chip which reduced system design cost. The IC also adopts high accuracy current sensing control method which maintains accurate output current and good line/load regulation. At the same time, OTP protection point can be adjusted by external resistance in different grades.KP1071LSPA integrates functions and protections of Current Limit and Leading-Edge Blanking, Under Voltage Lockout (UVLO), Cycle-by-cycle Current Limiting (OCP), Thermal Fold back (OTP), LED Short Protection, etc.