ON Semiconductor – NCP785A: Family of Very Wide Input Voltage Range Linear Voltage Regulators

ON Semiconductor’s new NCP785A is a high performance linear regulator, offering a very wide input voltage range of up to 450V, with an output current of 10mA. The NCP785A offers ±5% accuracy, extremely high power supply rejection ratio and ultra low quiescent current. The NCP785A is optimized for high voltage inputs, making it ideal for harsh environment applications.


  • 45V to 450V recommended VIN range allows to operate directly from rectified 120VAC/230VAC mains voltage
  • Ultra low quiescent current of typical 10μA helps to minimize system stand-by power consumption
  • Very high PSRR of typical 80dB at 120Hz allows for effective filtration of mains AC ripple
  • Option with dedicated enable pin (NCP785B) simplifies output voltage ON/OFF control


  • Industrial
  • Home automation
  • White Goods
  • Lighting
Part NumberVout (V)

NCP785A vs. Capacitive Dropper Comparison

NCP785A Power SupplyCapacitive Dropper AC/DC Power Supply
No Load Power324V* 10μA = 3.24mW~90mW (>20 times ON Semi Solution)
Solution Cost EstimationNCP785A IC, SOT89-3 Capacitor 2.2uF/450V Alu ±20% Rectifier diode, 1A, 1000V, DO-41 Capacitor 22uF/6.3V Cer. ±20%Total 80%Capacitor X1 type, 275VAC, 0.22μF Zener diode 5.1V, 0.5W, SOD123 Resistor 120Ω, 0.5W, 1210 ±5% Rectifier diode, 1A, 1000V, DO-41 (x2) Capacitor 220uF/6.3V Alu ±20%Total 100%
Output Accuracy±5%>±5% (AC mains ripple at the output) area
Solution Size~50% smaller sizeNeeds series X1 capacitor large PCB
Output NoisePSRR = 80dB at 100Hz, Noise = 240uVRMSOutput ripple of 200mV to 300mV when loaded