RT9742ANGJ5F

Overview

The RT9742ANGJ5F is a single N-channel high-side power switch IC designed for USB applications. It operates with a load voltage range of 2.7V to 6V and delivers a maximum output current of 1.5A. The device features a typical on-resistance of 55mΩ and requires no supply voltage (Vcc/Vdd). Key specifications include fixed over-current protection, thermal shutdown, reverse current blocking, and under-voltage lockout. A flag output indicates fault conditions, while an embedded delay function prevents inrush current misoperation. It is housed in a TSOT-23-5 package.

Feature Summary

• Integrates comprehensive protection mechanisms including fixed over-current, thermal shutdown, reverse current blocking, and under-voltage lockout.
• Provides a flag output signal to indicate fault conditions to the local USB controller.
• Features an embedded delay function to prevent misoperation caused by inrush current.
• Operates without a separate supply voltage, utilizing a low on-resistance N-channel MOSFET.

Applications

• USB peripheral power switching
• Notebook PC power distribution
• High-side load driver applications

Procurement Notes

Verify the specific suffix 'NGJ5F' against official Richtek documentation to confirm the exact pinout and electrical characteristics, as variations exist within the RT9742 family. Ensure the selected variant matches the required 1.5A current rating and 55mΩ on-resistance for the target application. Cross-reference the package type TSOT-23-5 with design constraints. Confirm RoHS compliance status if required by regulatory standards.

Selection Notes

Select this component when a cost-effective, low-voltage high-side switch is needed for USB interfaces. The 1.5A current rating and 55mΩ resistance suit moderate load requirements. The integrated flag output facilitates system monitoring. Consider the absence of a Vcc requirement for simplified circuit design. Evaluate the -40°C to 85°C operating temperature range against environmental conditions.

Part Context

The RT9742 series comprises single N-MOSFET high-side power switches optimized for USB applications. Variants differ in current ratings (0.5A to 3A) and on-resistance (55mΩ to 70mΩ). The RT9742ANGJ5F specifically denotes the 1.5A version with 55mΩ resistance in a TSOT-23-5 package. The family shares common protection features and interface logic.

Replacement Considerations

Substitutes must match the 1.5A current rating, 55mΩ on-resistance, and TSOT-23-5 package. Verify compatibility with the 2.7V-6V load voltage range and non-inverted input logic. Ensure equivalent protection features are present.

FAQ

Does the RT9742ANGJ5F require a separate supply voltage?

No, the device does not require a separate supply voltage (Vcc/Vdd).

What is the purpose of the flag output?

The flag output indicates fault conditions to the local USB controller.

How does the device handle inrush current?

It integrates an embedded delay function to prevent misoperation due to inrush current.