Fairchild Semiconductor’s IntelliMAX™ Load Switches Simplify Complex Power Design Challenges

Fairchild Semiconductor’s FPF1038 / FPF1039 advanced load management switches provide a monolithic, one-chip solution to the designers’ challenge of reducing in-rush current, or high di/dt, when a switch is used to disconnect loads with high (>100µF) output capacitances. If the load is connected directly to a battery or power supply using a conventional MOSFET/discrete solution, the tolerances of discrete components can create conditions where excessive droop can cause voltage rails to go out of regulation as the switch turns on and draws large currents. The FPF1038 / FPF1039 prevents this from occurring by integrating the necessary functionality into one chip, requiring less board space, reducing part counts, eliminating tolerance matching issues and additional design time to compensate the circuitry.

The FPF1038 / FPF1039 integrates a slew-rate controlled low-impedance MOSFET switch (21mΩ typical) and other features useful in embedded applications: ultra-low power consumption (<1µA), load discharge path, ESD protection, GPIO/CMOS compatible-enable circuitry. The devices also features a 1.2V to 5.5V input voltage operating range which aligns with supply rails for the latest embedded processors, custom ASICs, and FPGAs used in these applications. The optimized slew-rate controlled turn-on characteristics with TR=2.7mS prevent voltage droop on supply rails with bulk capacitances as large as 200µF.

The FPF1038 / FPF1039 expands Fairchild’s IntelliMAX™ portfolio to address the more dynamic power challenges of light industrial applications. The devices integrate functionality normally achieved through multi-chip solutions thereby providing designers off-the-shelf capability for their design needs, while reducing component count and increasing efficiency. Demonstration boards are available, by request only, from local Fairchild Semiconductor Sales Representatives.