The ML4805 is a controller for power factor corrected, switched mode power supplies. Similar to the ML4801, the ML4805 may be used for voltage mode operation. Key features of this combined PFC and PWM controller are low start-up and operating currents. 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 ML4805 includes circuits for the implementation of a leading edge, average current "boost" type power factor correction and a trailing edge pulse width modulator.