PCA9535ECMTTXG

I/o Expanders Overview

The PCA9535ECMTTXG is a 16-bit I/O expander manufactured by onsemi, designed for I2C and SMBus interfaces. It operates within a supply voltage range of 1.65V to 5.5V and supports clock frequencies up to 100 kHz. The device features open-drain outputs capable of sourcing or sinking 25mA, with an interrupt output capability. It is housed in a 24-QFN (4x4) package with exposed pad and functions across an extended temperature range of -55°C to +125°C. This component includes Power-On Reset (POR) functionality and is classified as obsolete.

I/o Expanders Feature Summary

• Provides 16 general-purpose digital input and output expansion via standard I2C and SMBus communication protocols.
• Includes an interrupt output pin that signals state changes to the host processor without continuous polling.
• Integrates internal configuration registers allowing individual pin direction setting and persistent state retention during power cycles.

I/o Expanders Applications

• Embedded systems requiring additional GPIO pins for sensor interfacing or peripheral control.
• Industrial automation controllers operating in wide temperature environments.
• Consumer electronics utilizing low-voltage logic levels for system expansion.

I/o Expanders Procurement Notes

This part number is officially marked as obsolete and no longer manufactured by onsemi. Verification of availability should focus on surplus distributors or secondary markets rather than direct manufacturer channels. Buyers must confirm the authenticity and storage history of existing stock due to the component's discontinued status. Cross-referencing with valid replacement parts from the same family or compatible manufacturers is recommended for new designs.

I/o Expanders Selection Notes

Designers should evaluate the 100 kHz maximum clock speed against higher-speed alternatives if system latency is critical. The 1.65V minimum supply voltage allows compatibility with low-power logic families, but the 25mA output current may limit direct driving of high-load peripherals. The 24-QFN package requires specific PCB footprint considerations for thermal dissipation and soldering processes compared to through-hole options.

I/o Expanders Part Context

The PCA9535ECMTTXG belongs to the broader PCA9535 series of I/O expanders produced by onsemi. While other variants like the PCA9535ECDTR2G offer similar functionality in TSSOP packages, this specific QFN variant is optimized for compact surface-mount applications. The series is widely recognized for its simplicity in expanding microcontroller I/O capabilities over serial buses.

I/o Expanders Replacement Considerations

Publicly confirmed substitute part numbers include MAX7313ATG+ from Analog Devices/Maxim Integrated. Designers should verify pinout compatibility and electrical specifications before substitution.