Fairchild Semiconductor - Boost Switch Delivers High Efficiency in High-Frequency Step-Up DC-DC Designs

Its Schottky diode has low reverse leakage current over temperature to prevent a lowering of the converter efficiency as the package temperature rises. The FDFME3N311ZT integrates two discrete devices into a compact (1.6mm x 1.6mm) and low-profile (0.55mm) MicroFET™ thin package, answering the need for compact DC-DC boost designs and offering a 36 percent space savings over prior boost switch products.

In applications such as cell phones, the FDFME3N311ZT offers a 30V breakdown voltage to drive up to seven or eight white LEDs, depending on the LEDs selected and design guardband. White LEDs are typically used for display backlighting in mobile devices such as cell phones, and are normally connected in a series path to ensure a uniform forward current and brightness for each LED. With each white LED having a forward voltage of around 3-3.5V, this boost switch is instrumental in “stepping-up” the available battery voltage and in most cases, a single cell lithium type.

This boost switch is another addition to Fairchild’s broad MOSFET portfolio. This portfolio offers a wide range of breakdown voltages (20V-1000V) and cutting-edge packaging technologies to solve the complex power and space challenges of today’s designs.