BP5178FH is a highly integrated high-precision single-stage linear LED constant current driver chip that supports high-voltage triac dimming. It is mainly used to drive various light sources and lamps with high power factor for mains input, and at the same time has good compatibility with triac dimmers. Based on linear constant current technology, BP5178FH can eliminate electrolytic capacitors and magnetic elements, helping LED drivers achieve small size, long life, and comply with EMI standards. BP5178FH can accurately set the LED current through an external resistor. By optimizing the input current under different input voltages, the chip can reduce losses and optimize system efficiency. BP5178FH can achieve good compatibility with triac dimmers by setting the bleeder current. BP5178FH has an over-temperature adjustment function. When the chip temperature is too high, the output current will be reduced.