Fairchild Semiconductor International, Inc. (Fairchild) has introduced a 6MHz 600mA synchronous Buck regulator, FAN5361. The FAN5361 delivers high efficiency in a compact and razor-thin footprint for designers of cell phones, datacards and netbooks. The higher switching frequencies lead to lower efficiencies and the FAN5361’s optimized design eases these losses with 91% peak efficiency. The light load efficiency of FAN5361 is 82% at 1mA load current.
By reducing wasted energy, this synchronous DC/DC step-down converter enables longer battery life and less heat dissipation in portable applications that continually strive to accommodate rich functionality.
The FAN5361 allows the use of tiny 470nH chip inductors and 0402 case size input and output capacitors. Compatibility with these passive components allows system designers to pick chip inductors and capacitors that consume less board space at a lower cost, resulting in smaller and more affordable end applications. This DC/DC converter is packaged in a 0.99 x 1.39mm WL-CSP package with a sleek, low profile of 0.6mm, conserving board space for these space-constrained applications.
This product uses a proprietary ultra-fast architecture offering robust transient response while consuming very low quiescent current, making the application more resilient to sudden fluctuations in processor or I/O loads. “In addition to handling large load steps with ease, this architecture minimizes system disturbances during gradual mode transitions as well,” said Peter Khairolomour, technical marketing manager at Fairchild. “When slowly ramping up the load across the pulse-frequency modulation (PFM) to pulse-width modulation (PWM) transition point, our customers will notice a very seamless transition as opposed to the output voltage overshoot often seen in more traditional architectures. This is especially important because the transition point occurs in the 150mA range where many loads spend a significant amount of their time.”
This solution operates at input voltages ranging from 2.3V to 5.5V, meeting the requirements for today’s single Li-Ion and multiple alkaline/NiMH cell applications. Fixed output voltage options are available ranging from 1.0V to 1.82V.
The FAN5361 is a portable solution from Fairchild that offer novel ways to address the daunting efficiency, space and performance challenges for portable applications. As portable applications continue to move to smaller and thinner geometries, power conservation and effective heat dissipation will become an even more critical design challenge and Fairchild will continue to develop new ways to tackle these power challenges.