Dimmable Quasi-Resonant Primary Side Current-Mode Controller for LED Lighting with Thermal Fold-back

The NCL30083 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 VCC Range
• Source 300 mA/Sink 500 mA Totem Pole Driver with 12 V Gate Clamp
• 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 (13 A typ.)
• 5 State Quasi−log Dimmable
• Thermal Fold−back
• Programmable soft−start
• Wide Temperature Range of −40 to +125°C
• Pb−free, Halide−free MSL1 Product
• Robust Protection Features
   ♦ Over Voltage / LED Open Circuit Protection
   ♦ Over Temperature 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