The ML4841 is a controller for power factor corrected, switched mode power supplies. Power Factor Correction (PFC) allows the use of smaller, lower cost bulk capacitors, reduces power line loading and stress on the switching FETs, and results in a power supply that fully complies with IEC1000-2-3 specifications. The ML4841 includes circuits for the implementation of a leading edge, average current, "boost" type power factor correction, and a trailing edge, pulse width modulator (PWM).