The FPF1321UCX is a dual-input single-output (DISO) IntelliMAX™ load switch designed for seamless power-source transitions between two input power rails. It features a low on-resistance of 50 mΩ (typical at 3.3V) and operates over a wide input voltage range of 1.5V to 5.5V. The device provides True Reverse-Current Blocking (TRCB) to prevent unwanted current flow from output to input. A key feature of the FPF1321UCX is its integrated 65 Ω resistor for quick output discharge and a controlled slew rate with a typical rise time of 130 µs to prevent inrush current. This switch is ideal for power management in portable devices such as smartphones, tablet PCs, and NFC-capable SIM card power supplies.