Power control ICs

Renesas has announced the R2A20114 series of power factor correction control ICs employing continuous conduction mode interleaving to enable implementation of compact, highly efficient, low-noise power supply units for high-power products such as computer servers and air conditioners.

A PFC IC is a device in the power supply unit of a product, such as a computer server or digital home appliance, that reduces the generation of unnecessary power and harmonics caused by differences between the input voltage and current waveforms during AC to DC conversion.

It accomplishes this by shaping the input current waveform to match the input voltage waveform. In recent years, the use of PFC control ICs in power supply units has become widespread to improve energy efficiency and ensure compliance with international regulations covering harmonics.

The series employs three functions, including interleaving, to enable implementation of power supply units that are more efficient and generate less noise.

With reduction of ripple current, by up to a quarter, the series is the first continuous conduction mode PFC control IC from the company using interleaving for higher efficiency. In interleaved operation a pair of two boost circuits operates alternately to shape the input current waveform.

High conversion efficiency in all load areas is achieved through improvement of efficiency under light loads.

The series has a function that stops one of the boost circuits when operating under a light load not requiring high output power. This makes possible the previously difficult task of improving efficiency under a light load and realises high conversion efficiency to be achieved at almost all load demands.

There is about a 6 dB noise reduction than earlier products.

The series allows a thinner design and more compact power supply units. It also integrates a variety of protection circuits, including a protection function for interleaving operation, which improve the reliability of the power supply system and reduces the number of component parts required for greater simplicity.