Fairchild Semiconductor announced that it is providing designers of cell phones, datacards and netbooks a 6MHz synchronous Buck regulator that is said to deliver high efficiency in a compact and razor-thin footprint. Higher switching frequencies typically lead to lower efficiencies. However, Fairchild says that the FAN5361’s carefully optimized design mitigates these losses leading to 91% peak efficiency. The device has a light load efficiency of 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.
The FAN5361, a 6MHz 600mA Buck regulator, allows the use of tiny 470nH chip inductors and 0402 case size input and output capacitors. Fairchild states that 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 Semiconductor. "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 2.3 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 1.0 to 1.82V.
The units are priced (each, 1000 pcs.) at $ US 0.78 with a delivery of12 weeks ARO.