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20 Feb 2017, 12:02

The Benefits of Very High Input Voltage Linear Regulators

Most home appliances and connected devices such as occupancy sensors and smoke alarms take direct AC input from the mains of the home. This presents the challenge of integrating an AC/DC power supply into the often tiny enclosure, along with the components that make up the core functionality of the device. The traditional solution is to utilize a capacitive dropper power supply. However, these solutions are often large, inefficient, and noisy due to the large capacitor required. 

Wide input voltage regulator based AC/DC power supplies offer a unique solution that addresses the disadvantages of the capacitive dropper method. These devices provide a small, stable, and accurate solution that consumes very little power at no load when compared to capacitive dropper solutions.

Value Advantage Compared to Non-Isolated SMPS or Capacitive Dropper Solutions:

  • Provides Smaller Solution Size
  • Enables Reduction in Solution Cost
  • Assures Lower Output Noise and Better Accuracy
  • Improves Standby Power Consumption
  • No Inductor or Transformer Required



ON Semiconductor’s family of high-performance 5 mA and 10 mA linear regulators offer a very wide operating input voltage range of up to 450 V DC operating and 700V DC maximum. The devices are an ideal choice for high input voltage applications under harsh environmental conditions such as industrial and home automation, smart metering, and home appliances. The devices offer ±5% output voltage accuracy, extremely high power supply rejection ratio, and ultra-low quiescent current. The NCP786L (123-8829) is offered as adjustable voltage regulator with output voltages from 1.27V to 15V, and the NCP785A (882-9770) is available with fixed output voltages: 3.3 V, 5.0 V, 12 V, 15 V.


  • Up to 450 V DC operating Vin & 700 V DC Maximum Vin
  • Guaranteed Output Current of 5mA (NCP786L) and 10 mA (NCP785)
  • ±5% Accuracy Over Line and Temperature
  • Over-current and Short-Circuit Protection
  • Thermal Shutdown Protection
  • PSRR
    • NCP786L: 70 dB @60 Hz, 90dB @ 100kHz
    • NCP785: 80 dB @ 120 Hz
  • Quiescent Current
    • NCP786L: 10µA typ.
    • NCP785: 15µA typ.


  • Directly converts AC high voltage down to low-voltage DC
  • Immune against VIN spikes
  • Effectively reduces input ripple
  • Greatly reduces power consumption
  • Ideal for space constrained applications
  • Considerably simplifies Power Supply design

Markets & Applications:

  • IoT Connected Devices, Home Appliances, and Home Automation
  • Smart E-meters, Circuit Breakers, Fire Alarms, and Occupancy Sensors
  • Low-power MCU Applications Power Supply
  • Smaller Size, No-load Efficient replacement for Capacitive Dropper



ON Semiconductor Channel Marketing

20 Feb 2017, 12:02


April 5, 2017 07:10

Good idea, however to create a microcontroller based application that communicates frequently with only 10mA budget could be quite challenging.

0 Votes

August 16, 2017 07:16

@marjanhanc Great feedback! Check out the NCP781, our latest release in this family supporting up to 100 mA.