RT9742UNGJ5

Overview

The RT9742UNGJ5 is a single N-channel high-side power switch IC designed for USB applications. It operates within a load voltage range of 2.7V to 6V and features an integrated N-MOSFET with a typical on-resistance of 55mΩ. The device supports flexible current ratings, including options for 3A, 2.5A, 2A, 1.5A, 1A, and 0.5A continuous output currents. It incorporates comprehensive protection mechanisms such as fixed current limiting, thermal shutdown, reverse current blocking, and under-voltage lockout (UVLO). An embedded delay function prevents misoperation due to inrush current, while a flag output indicates fault conditions.

Feature Summary

• Integrates an open-drain fault flag output to signal error states to the local controller
• Includes an embedded delay function to prevent misoperation caused by inrush current
• Provides complete protection against over-current, short circuits, thermal overload, and reverse current flow

Applications

• USB power supply distribution
• Portable battery-operated equipment
• Bus-powered Universal Serial Bus applications

Procurement Notes

Verify the specific suffix code to confirm the exact current rating variant, as the RT9742 family offers multiple options ranging from 0.5A to 3A. Ensure the package type matches the design requirements, typically TSOT-23-5 or SOT-23-5. Confirm RoHS compliance status and moisture sensitivity level before integration into the manufacturing process.

Selection Notes

Select this component when a low-cost, low-voltage high-side switch is required for USB interfaces. Consider the specific current rating suffix needed for the load application. The device is suitable for designs requiring compact surface-mount packaging and built-in diagnostic flagging capabilities without external components.

Part Context

The RT9742 series consists of cost-effective, low-voltage single N-MOSFET high-side power switches. These ICs are optimized for USB applications, offering low switch-on resistance and low supply current. The family is available in various packages, including TSOT-23-5, TSOT-23-5 (FC), and SOT-23-3, to support flexible board space constraints.

Replacement Considerations

RT9742AGJ5F

FAQ

Does the RT9742 support hot plug-in applications?

Yes, the device includes an embedded delay function that limits inrush current, making it suitable for hot plug-in applications.

What protection features are integrated into the RT9742?

The IC integrates over-current protection, a short fold-back circuit, thermal shutdown, under-voltage lockout, and reverse current flow blocking.