Date: 19/02/2009

Fairchild Semiconductor's PFC controller delivers >96 % efficiency

Fairchild Semiconductor launched a new boundary-conduction mode (BCM) interleaving power factor correction (PFC) controller, which provides over 96 % power conversion efficiency for AC-DC power supplies. Applications include power supplies for digital TVs, desktop and entry-level server computers, front-end telecom systems and industrial power systems rated from 100W to 1000W. Historically, the higher-efficiency and lower-cost BCM PFC converters are limited to about 300W of maximum power level. Interleaving extends the power range of BCM control while ripple current cancellation minimizes high peak currents. By interleaving and keeping two power stages precisely at 180 degrees out of phase timing under all operating conditions, the FAN9612 lowers conduction losses. These energy-conservation benefits are integral in helping customers meet the latest ENERGY STAR and Climate Savers Computing Initiative requirements.

By the interleaving of the power trains, the FAN9612 is also able to reduce the input filter size and reduce board space by as much as ten percent compared to alternate solutions.
The FAN9612 incorporates below set of features:

Automatic phase disable to operate with only one channel under light-load conditions, minimizing power losses.
A low start-up and operating current
Valley switching technology, minimizing losses as MOSFET turn-on
Over-current and power-limit protection for each channel
Two-level output over-voltage protection (OVP)
Input brownout protection and line OVP
Minimum restart timer frequency to avoid audible noise
Maximum switching frequency clamp
Programmable closed-loop soft-start, which minimizes output voltage overshoot at start-up.
Input voltage feed-forward function that minimizes output voltage variation versus line voltage.

Package: 16 lead SOIC
Price: Each $1.30 for 1K pieces
Availability: Samples available upon request