PCA9554ARGVR

I/o Expanders Overview

The PCA9554ARGVR is an 8-bit I/O expander for the I2C and SMBus interfaces, manufactured by Texas Instruments. It operates within a supply voltage range of 2.3 V to 5.5 V and supports clock frequencies up to 400 kHz. The device features three hardware address pins (A0, A1, A2) allowing up to eight units on a single bus. It includes configuration registers, polarity inversion, and an open-drain active-low interrupt output. Packaged in a 16-pin VQFN (RGV) format, it provides general-purpose parallel input/output expansion with latched outputs capable of directly driving LEDs.

I/o Expanders Feature Summary

• Open-drain active-low interrupt output signals state changes to the system master
• Three hardware address pins enable multiple devices on the same I2C/SMBus
• Internal power-on reset initializes registers and state machine upon power application

I/o Expanders Applications

• Remote I/O expansion for microcontroller families via I2C interface
• Direct LED driving applications utilizing high-current drive capability
• Systems requiring additional GPIOs for sensors, buttons, or fans

I/o Expanders Procurement Notes

Verify the specific RGV package variant matches the required footprint dimensions of 4.00 mm x 4.00 mm. Confirm that the fixed I2C address corresponds to the PCA9554A series rather than the standard PCA9554, as they share identical functionality but differ in addressing. Ensure pull-up resistors are correctly sized for the INT, SDA, and SCL lines according to the bus capacitance requirements.

I/o Expanders Selection Notes

Select this component when a remote 8-bit I/O expander with interrupt capabilities is needed for I2C systems operating between 2.3 V and 5.5 V. It serves as a pin-compatible alternative to the PCF8574 series, though software modifications are necessary due to enhanced features like configuration registers. Consider the VQFN-16 package if space-constrained surface-mount assembly is required.

I/o Expanders Part Context

The PCA9554A belongs to the broader PCA95xx family of I2C and SMBus logic ICs from Texas Instruments, which includes repeaters, switches, and expanders. This specific model is designed to provide general-purpose I/O expansion for most microcontroller families. It is functionally identical to the PCA9554 except for its fixed I2C address, allowing both variants to coexist on the same bus.

I/o Expanders Replacement Considerations

The PCA9554DW is listed as obsolete with TCA9554DWR and TCA9554PWR suggested as substitutes. Verify compatibility regarding the I2C address differences between the PCA9554 and PCA9554A families before substituting.