Capacitive linear output LED driving power supply

The invention discloses a capacitive linear output LED driving power supply. Voltage conversion is carried out directly based on the principle of high-frequency capacitor charging and discharging. Two MOSFETs respectively control capacitor charging and discharging at working frequency of 20KHZ to 200KHZ to realize voltage conversion. Based on the fact that the input voltage and output power have a linear relationship when the capacity of a capacitor is fixed and the capacitor has constant power characteristic within a certain scope of output power, damage to LED lamps due to voltage change is avoided, and the service life of LED lamps is prolonged. The LED driving power supply disclosed by the invention has the advantages of simple structure, low cost, and small size. The LED driving power supply meets the driving requirement for constant power output within the large range of change of the number of LED lamp beads from 100% to 200%. The effect is more obvious at low power. The efficiency is 84-94% at 3-50 watts. The power factor is 0.9-0.98. When the power is 50 watts to hundreds of watts, the conversion efficiency can reach 95-97%, and the power factor is up to 0.92 to 0.98.