SX1508QBIULTRT

Overview

The SX1508QBIULTRT is an ultra-low voltage General Purpose Input/Output (GPIO) expander manufactured by Semtech. It features eight I/O channels and communicates via a standard 400kHz I2C serial interface. The device operates within a supply voltage range of 1.2V to 3.6V, with a maximum clock frequency of 2MHz. It supports open-drain and push-pull output configurations with drive currents of 8mA and 15mA. The component includes interrupt output capabilities, power-on reset, and a reset input (NRESET). It is housed in a 20-pin QFN-UT package with exposed pad, rated for operation between -40°C and +85°C, and offers 2kV ESD protection.

Feature Summary

• Ultra-low voltage operation suitable for battery-powered handheld equipment
• Integrated LED driver and keyboard engine functionality
• Global level shifting capability across multiple voltage domains
• Interrupt output support for efficient event handling

Applications

• Low-power handheld battery-operated devices
• Systems requiring serial expansion of I/O ports
• Remote control and monitoring applications

Procurement Notes

Verify the specific suffix 'QB' against official Semtech documentation to confirm voltage and feature specifications, as suffixes often denote distinct electrical characteristics or packaging variants. Ensure the QFN-20 package footprint matches the target PCB design. Confirm RoHS compliance status through the manufacturer's current datasheet rather than distributor summaries.

Selection Notes

Select this component when microcontrollers lack sufficient I/O ports or require remote serial control. It is appropriate for designs needing global level translation between different voltage domains. Consider the 1.2V minimum operating voltage for compatibility with low-voltage logic families. Verify that the 400kHz I2C speed meets system timing requirements.

Part Context

This part belongs to the SX1508 family of GPIO expanders from Semtech. The family includes variants like SX1507B, SX1508B, and SX1509QB, offering 4, 8, and 16-channel configurations. These devices are designed to provide additional control and monitoring capabilities in systems where direct MCU connections are insufficient.

Replacement Considerations

Check for SX1508BIULTRT if the 'B' variant is available, but verify if the 'QB' specific features are required. Other family members like SX1509QB offer 16 channels if more I/O is needed. Cross-reference pinouts and register maps before substitution.