Power Factor Controller Provides Low THD Plus Maximum Efficiency over Wide Voltage Ranges

Intersil Corporation has introduced a new active power factor controller that delivers minimal harmonic distortion (THD) and high power factor (PF) correction. The ISL6730A features a patent-pending breakthrough in negative capacitance technology which reduces EMI filter size, improves THD and PF and provides maximum efficiency over a wide input supply range and output power (input voltages from 85VAC to 270VAC and power range from 50W to 2kW). This technology also minimizes zero crossing distortion, compensates for input filter capacitance PF displacement error and reduces the magnetic component size by up to 66 percent. For example, in an 85W power supply, the EMI filter inductor can be reduced from 150uH to 56uH. The small external components result in a lower cost design with improved performance.

The device’s power factor correction capability is compatible with the requirements for a power factor higher than 0.9, as currently required by ENERGY STAR Program Requirements for Computers Version 5.0. The ISL6730A also achieves excellent light load efficiency using integrated skip-mode, and includes an internally clamped 12.5V gate driver delivering 1.5A peak current to the external power MOSFET. The ISL6730A enables a reliable system that is fully protected with features such as cycle-by-cycle over-current, power limiter, over-temperature, input brownout, output over-voltage and under-voltage protection.

Features and specifications of the new controller include: Negative capacitance generator reduces component size requirements; Excellent power factor and total harmonic distortion over a wide supply and output power range; Excellent light load efficiency; and Internally clamped 12.5V gate driver delivers 1.5A peak current to the external power MOSFET.

The ISL6730A is available now in compact 10-lead MSOP package, with prices starting at $0.95 each in 1,000-unit quantities.