New Industry Products

Constant-Voltage Primary-Side-Regulation PWM Controller for PFC

August 28, 2017 by Paul Shepard

The FL7740 from ON Semiconductor provides accurate CV regulation in the steady state with differentiated dynamic function to minimize overshoot and undershoot of output voltage in line and load transient condition.

Standby power is less than 0.3W for smart lighting application and power factor is higher than 0.9 even at half load condition when enabling PF optimizer for wide output power scalability.

Startup time is less than 0.2 seconds with built-in high voltage startup circuit and output voltage quickly reaches to the target CV level by loop gain transition technique during startup.

Various protections such as over load, output diode short, sensing resistor short, output short and output over voltage protection guarantee high system reliability.

Features include:

  • Wide universal input range (90- to 305-VacAC)
  • Precise CV regulation in the steady state : < ± 3 %
  • CV regulation in the load transient : < ±10 %
  • Overshoot-less fast HV start up time (< 0.2 sec )
  • Low standby power
  • PF higher than 0.9 at high-line and half load by PF optimizer
  • Pulse-by-pulse current limit
  • Output short protection
  • Output over voltage protection
  • Output diode short protection
  • Sensing resistor short & open protection
  • Over load protection

Typical applications are expected to include LED lighting systems, ac-dc adapters, TVs, monitors, and a variety of off-line appliances requiring power factor correction.