New Industry Products

Dimmable LED Driver with Primary Side CC/CV Control and Digital PFC

August 12, 2018 by Paul Shepard

The NCL30386 from ON Semiconductor is a power factor corrected controller targeting isolated and non−isolated “smart−dimmable” constant−current LED drivers. Designed to support flyback, buck−boost and SEPIC topologies, the controller operates in a quasi−resonant mode to provide high efficiency.

Thanks to a novel control method, the device is able to tightly regulate a constant LED current and voltage from the primary side. This removes the need for secondary−side feedback circuitry, its biasing and for an optocoupler. The device also provides near−unity power factor correction.

The device is highly integrated with a minimum number of external components. A robust suite of safety protection is built in to simplify the design. This device is specifically intended for very compact space efficient designs and supports analog and digital dimming with two dedicated dimming inputs control ideal for Smart LED Lighting applications.

Typical applications are expected to include integrated LED bulbs, LED power driver supplies and LED light engines.

Performance advantages include:

  • Accurate brightness regulation
  • High integration with a minimum number of external components - simple design
  • High PF/Low THD that meets and exceeds regulatory standards
  • High efficiency
  • Enables the devices to tightly regulate a constant LED current from the primary side - no secondary side feedback circuitry necessary

Typical Application Schematic for NCL30386 (click on schematic to enlarge)

Summary of features & specifications:

  • High Voltage Startup
  • Quasi−resonant Peak Current−mode Control Operation
  • Primary Side Feedback
  • CC / CV Control
  • Tight LED Constant Current Regulation of ±2% Typical
  • Digital Power Factor Correction
  • Analog and Digital Dimming
  • Cycle by Cycle Peak Current Limit
  • Wide Operating VCC Range
  • Operating temperature range of −40 to + 125°C
  • Robust Protection Features
    • Brown−Out
    • OVP on VCC
    • Constant Voltage / LED Open Circuit Protection
    • Winding Short Circuit Protection
    • Secondary Diode Short Protection
    • Output Short Circuit Protection
    • Thermal Shutdown