Dimmable Quasi-Resonant Primary Side Current-Mode Controller for LED Lighting

The NCL30081 is a PWM current mode controller targeting isolated flyback and non−isolated constant current topologies. The controller operates in a quasi−resonant mode to provide high efficiency. Thanks to a novel control method, the device is able to precisely regulate a constant LED current from the primary side. This removes the need for secondary side feedback  circuitry, biasing and an optocoupler.

FEATUREs
• Quasi−resonant Peak Current−mode Control Operation
• Primary Side Sensing (no optocoupler needed)
• Wide VCCRange
• Precise LED Constant Current Regulation ±1% Typical
• Line Feed−forward for Enhanced Regulation Accuracy
• Low LED Current Ripple
• 250 mV ±2% Guaranteed Voltage Reference for Current Regulation
• ~ 0.9 Power Factor with Valley Fill Input Stage
• Low Start−up Current (10 A typ.)
• Small Space Saving Low Profile Package
• 5State Quasi−log Dimmable
• Wide Temperature Range of −40 to +125°C
• Pb−free, Halide−free MSL1 Product
• Robust Protection Features
  ♦ Over Voltage / LED Open Circuit Protection
  ♦ Secondary Diode Short Protection
  ♦ Output Short Circuit Protection
  ♦ Shorted Current Sense Pin Fault Detection
  ♦ Latched and Auto−recoverable Versions
  ♦ Brown−out
  ♦ VCC Under Voltage Lockout
  ♦ Thermal Shutdown

Typical Applications
• Integral LED Bulbs
• LED Power Driver Supplies
• LED Light Engines