PCA9555BS,118

I/o Expanders Overview

The PCA9555BS,118 is a 24-pin CMOS device providing 16-bit General Purpose parallel Input/Output (GPIO) expansion for I²C-bus/SMBus applications. It operates within a power supply voltage range of 2.3 V to 5.5 V and supports clock frequencies from 0 Hz to 400 kHz. The device features 5 V tolerant I/Os, an active LOW interrupt output, and low standby current. It includes noise filters on SCL/SDA inputs, internal power-on reset, and ESD protection exceeding 2000 V HBM. Packaged in HVQFN24 (SOT616-1), it allows up to eight devices to share the same bus via hardware address pins A0, A1, and A2.

I/o Expanders Feature Summary

• Provides 16 bits of GPIO expansion with individual input/output configuration capabilities
• Features an open-drain interrupt output activated when input states differ from port registers
• Includes polarity inversion registers to allow active HIGH or active LOW operation

I/o Expanders Applications

• ACPI power switches
• Sensor interface connections
• Push button scanning
• LED driving circuits
• Fan control systems

I/o Expanders Procurement Notes

Verify the ordering suffix ',118' corresponds to the HVQFN24 package in reel packing method Q1/T1. Confirm that the component meets RoHS compliance standards as specified in the product data sheet. Ensure the supplier provides documentation verifying the part number matches NXP Semiconductors specifications for the PCA9555 series.

I/o Expanders Selection Notes

Select this component when pin-to-pin compatibility with PCF8575 is required but enhanced drive capability and lower supply current are needed. Note that software changes are necessary due to enhancements over the PCF8575 family. Use this device if the application requires 5 V I/O tolerance and independent I/O configuration for mixed input/output scenarios on a single I²C bus.

I/o Expanders Part Context

The PCA9555BS,118 belongs to the PCA9555 series developed to enhance the NXP Semiconductors family of I²C-bus I/O expanders. It shares the same fixed I²C-bus address as the PCA9554, allowing mixed combinations of these devices on the same bus. The BS variant specifically denotes the HVQFN24 package, offering smaller packaging compared to traditional SO or SSOP options while maintaining thermal performance through the exposed pad.

I/o Expanders Replacement Considerations

The PCA9555 is pin-to-pin compatible with the PCF8575; however, software modifications are required due to functional enhancements. Other variants in the PCA9555 family include PCA9555D, PCA9555DB, PCA9555PW, and PCA9555HF, which offer different package types such as SO24, SSOP24, TSSOP24, and HWQFN24.