RT9742GGJ5F

Overview

The RT9742GGJ5F is a single N-channel high-side power switch IC designed for USB applications. It operates within a voltage range of 2.7V to 6V and features a maximum on-resistance of 70mΩ with a typical output current of 1A. The device integrates comprehensive protection mechanisms including fixed over-current protection, short circuit fold-back, thermal shutdown, and under-voltage lockout (UVLO). A flag output indicates fault conditions, while an embedded delay function prevents misoperation from inrush currents. It is housed in a TSOT-23-5 package.

Feature Summary

• Integrates over-current protection, short fold-back, thermal shutdown, and UVLO circuits.
• Features a flag output to indicate fault conditions to the local controller.
• Includes an embedded delay function to prevent misoperation due to inrush current.

Applications

• USB peripherals
• Notebook PCs

Procurement Notes

Verify the specific suffix GGJ5F against official Richtek documentation to confirm the exact current rating and resistance parameters, as these vary across the RT9742 family. Ensure the ordering code matches the required package type and electrical specifications for your design.

Selection Notes

Select this component when a low-voltage high-side switch with integrated fault indication is required. The 1A current rating and 70mΩ resistance suit standard USB peripheral loads. Consider the TSOT-23-5 package for space-constrained designs requiring surface mount installation.

Part Context

The RT9742 series comprises cost-effective, low-voltage power switches optimized for USB power distribution. Variants differ by current handling capabilities ranging from 0.5A to 3A and on-resistance values of 55mΩ or 70mΩ. All variants share similar protection features and package options like TSOT-23-5.

Replacement Considerations

Other RT9742 variants such as RT9742AGJ5F (3A) or RT9742VGJ5F (2A) may serve as functional substitutes if higher current capacity is acceptable. Verify pin compatibility and parameter alignment before substitution.

FAQ

What is the purpose of the flag output?

The flag output provides a signal to the local USB controller to indicate that a fault condition has occurred.

How does the device handle inrush current?

The chip integrates an embedded delay function to prevent misoperation caused by inrush currents during turn-on.