The AAT1121IES-0.6-T1 is a high-efficiency, current-limited power switch manufactured by Advanced Analog Technology (now Skyworks Solutions). It is designed to protect USB ports and other power interfaces from overcurrent and short-circuit conditions. This device provides a controlled current limit and automatically shuts down the output when an overcurrent or short-circuit condition is detected.

Applications

• USB port power management
• Peripheral device power
• Hot-swap applications
• Notebook computers
• Desktop computers
• Portable devices

Features

• Adjustable current limit
• Overcurrent and short-circuit protection
• Thermal shutdown
• Reverse blocking
• Low on-resistance (typically around 80 mΩ)
• Enable/disable control
• Soft-start
• Small SOT23-5 package

Benefits

• Protects USB ports and connected devices from damage due to overcurrent and short-circuit conditions.
• Improves system reliability by preventing system crashes caused by power faults.
• Reduces the need for external components, simplifying circuit design.
• Conserves power by shutting down the output during fault conditions.
• Provides a controlled and predictable current limit.

Technical Specifications

The AAT1121IES-0.6-T1 operates with an input voltage range of typically 2.5V to 5.5V. The current limit is adjustable using an external resistor. The device incorporates thermal shutdown protection, which disables the output when the junction temperature exceeds a predetermined threshold. The low on-resistance minimizes power loss and heat dissipation. The SOT23-5 package enables a compact PCB layout.

The enable/disable pin allows the power switch to be turned on or off under external control. The soft-start feature limits inrush current during startup, minimizing voltage droop and stress on the power supply. Reverse blocking prevents current flow from the output to the input when the device is disabled.