PCA9557BS,118

I/o Expanders Overview

The PCA9557BS,118 is an 8-bit I/O expander designed for SMBus and I2C applications. It features a 2.3 V to 5.5 V supply range and supports clock frequencies up to 400 kHz. The device includes an internal power-on reset, noise filters on SCL/SDA inputs, and a low-active reset input. It offers open-drain outputs with 5 V tolerance and operates within a temperature range of -40°C to +85°C. Packaged in HVQFN16, it provides parallel I/O expansion with configurable input/output settings.

I/o Expanders Feature Summary

• Configurable 8-bit I/O ports via dedicated configuration registers
• Integrated polarity inversion register for input signal manipulation
• Low-active reset input allows system initialization without power cycling
• Noise filtering on serial interface lines enhances signal integrity

I/o Expanders Applications

• SMBus and I2C bus peripheral expansion
• Parallel-to-serial data conversion in embedded systems
• General-purpose input/output extension for microcontrollers
• Industrial control interfaces requiring voltage level shifting

I/o Expanders Procurement Notes

This component is officially marked as obsolete by NXP Semiconductors and is no longer manufactured. Distributors may list remaining stock or recommend substitutes. Verify end-of-life status directly with the manufacturer before finalizing designs. Availability is not guaranteed, and lead times vary significantly if surplus inventory exists.

I/o Expanders Selection Notes

Select this part only if legacy compatibility with existing PCB layouts is required. Consider newer NXP I/O expanders with active production status for new designs. Ensure the HVQFN16 package footprint matches your assembly capabilities. Verify that the 400 kHz speed and 5 V tolerant inputs meet your system requirements.

I/o Expanders Part Context

The PCA9557 series belongs to NXP's family of I2C/SMBus I/O expanders. The BS suffix indicates the HVQFN16 package variant. This specific part number represents a discontinued generation of silicon CMOS circuits designed for reliable parallel I/O expansion in constrained space applications.

I/o Expanders Replacement Considerations

NXP recommends checking their official substitution guide for active alternatives. Common replacements include the PCA9557BR or other members of the PCA95xx series with updated packaging. Verify pinout compatibility and electrical specifications before swapping.

I/o Expanders FAQ

Does the PCA9557BS,118 support interrupt-driven operations?

No, the datasheet specifies that this variant does not include an interrupt output pin.

What is the maximum clock frequency supported?

The device supports standard mode I2C and SMBus operations up to 400 kHz.