PCA9535AHF,128

I/o Expanders Overview

The PCA9535AHF,128 is a low-voltage 16-bit General Purpose Input/Output (GPIO) expander designed for I2C-bus and SMBus applications. It provides a flexible set of GPIOs with an operating power supply voltage range of 1.65 V to 5.5 V. The device features four pairs of 8-bit Configuration, Input, Output, and Polarity Inversion registers. It includes an open-drain active LOW interrupt output activated when input states differ from the Input Port register state. The component supports Fast-mode I2C-bus communication up to 400 kHz and offers Schmitt-trigger action on SCL and SDA inputs. It operates within a temperature range of -40 °C to +85 °C and is housed in a HWQFN24 package.

I/o Expanders Feature Summary

• Pin and function compatible with PCA9535
• Open-drain active LOW interrupt output
• Internal power-on reset initializes default states
• Latch-up performance exceeds JESD78 Class II

I/o Expanders Applications

• ACPI power switches
• Sensor interfaces
• Push button detection
• LED control
• Fan control systems

I/o Expanders Procurement Notes

Verify the specific ordering suffix HF against the manufacturer's current documentation to confirm the HWQFN24 package type. Ensure the procurement channel sources directly from NXP Semiconductors or authorized distributors to guarantee authenticity. Confirm that the received components match the specified RoHS compliance status and are free from physical damage prior to integration into the design.

I/o Expanders Selection Notes

Select this component when interfacing with microprocessors requiring additional I/Os while minimizing interconnections. The wide VDD range supports next-generation devices with dropping supply levels. Verify that the system requires an open-drain interrupt output and that the 25 mA sink capability meets the load requirements. Ensure the PCB layout accommodates the thermal pad requirements of the HWQFN24 package for proper heat conduction.

I/o Expanders Part Context

This part belongs to the PCA9535A series, which serves as a pin-to-pin replacement for the standard PCA9535. It is distinct from the PCAL9535A, which offers Agile I/O features. The device is manufactured by NXP Semiconductors and is designed to interface with industry-standard I2C/SMBus controllers. It provides a simple solution for expanding GPIO capabilities in embedded systems.

I/o Expanders Replacement Considerations

The PCA9535AHF,128 is a direct pin-to-pin replacement for the PCA9535. Designers should verify compatibility with existing designs using the standard PCA9535. Other variants such as the PCA9535APW offer different packaging options but maintain functional equivalence.