PCAL6408ABSHP

I/o Expanders Overview

The PCAL6408ABSHP is an 8-bit general-purpose I/O expander manufactured by NXP Semiconductors, designed for remote I/O expansion via the I2C-bus interface. It operates within a supply voltage range of 1.65 V to 5.5 V and supports fast-mode communication up to 400 kHz. The device features bidirectional voltage-level translation between the SDA/SCL lines and Port P, which can operate at 1.8 V, 2.5 V, 3.3 V, or 5 V. Packaged in an HVQFN16 format (SOT758-1), it includes an active LOW reset input, an open-drain interrupt output, and Agile I/O capabilities such as programmable drive strength and internal pullup/pulldown resistors.

I/o Expanders Feature Summary

• Bidirectional voltage-level translation allows seamless communication between low-voltage microcontrollers and higher-voltage peripherals.
• Agile I/O features include software-configurable push-pull or open-drain outputs, programmable drive strength, and latchable inputs.
• Integrated interrupt logic with maskable channels and status registers minimizes host controller response time for fast-moving inputs.
• Internal power-on reset and active LOW external reset pin ensure reliable initialization without de-powering the device.

I/o Expanders Applications

• Battery-powered mobile applications requiring sensor and keypad interfacing
• Industrial control systems needing mixed-signal environment compatibility
• Consumer electronics utilizing push buttons and LED arrays

I/o Expanders Procurement Notes

Verify the ordering part number PCAL6408ABSHP against the manufacturer's datasheet to confirm the HVQFN16 package type and standard marking. Ensure the application design accounts for the dual power rail requirements: VDD(I2C-bus) for the interface side and VDD(P) for the port side. Confirm that the system voltage levels fall within the specified 1.65 V to 5.5 V operating range for proper functionality.

I/o Expanders Selection Notes

Select this component when an 8-bit GPIO expansion is required alongside voltage translation between incompatible logic levels. The PCAL6408A serves as a pin-to-pin replacement for the PCA6408A but offers enhanced Agile I/O features. Consider the HVQFN16 package if space constraints require a compact footprint. Verify that the target application benefits from the latched input feature and configurable interrupt masking for noise immunity.

I/o Expanders Part Context

The PCAL6408A belongs to NXP's family of low-voltage translating I/O expanders. It is functionally similar to the PCA6408A but includes additional configuration registers for Agile I/O features. The ABSHP suffix indicates the specific HVQFN16 package variant supplied in reel packaging. This series is designed to simplify interconnections in systems where processors and peripherals operate at different voltage domains.

I/o Expanders Replacement Considerations

The PCA6408A is a compatible predecessor; however, the PCAL6408A powers up with all interrupts masked by default, unlike the PCA6408A. Designers must update firmware to handle the new Agile I/O registers if migrating from the older part. Other packages like TSSOP16 or XQFN16 are available but require board layout adjustments due to pinout differences.