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PCA9535AHF

PCA9535AHF

MPN: PCA9535AHF,128
NXP USA Inc.
I/O Expander 16 I2C, SMBus 400 kHz 24-HWQFN (4x4)
Active3,790 in stock
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Overview

The PCA9535AHF is a 16-bit I/O expander designed for I2C and SMBus applications, providing a simple solution for expanding GPIO count via a serial interface. It features two 8-bit configurations and an active-low interrupt output, operating across a wide voltage range of 1.65V to 5.5V with very low standby current.

Why Choose This Part

This device offers excellent low-power performance with a standby current of only 1.5 microamps and supports a broad supply voltage range down to 1.65V. The push-pull output stage simplifies design by eliminating the need for external pull-up resistors for logic outputs, while the 4x4mm HWQFN24 package provides a compact footprint for space-constrained designs.

Applications

LED Driving
Utilizing the 25 mA drive capability and latched outputs to directly control status LEDs without external transistors.
User Interface Expansion
Interfacing with multiple push-buttons or DIP switches using the 16 I/O pins and the interrupt output to notify the host MCU of state changes.
System Monitoring
Monitoring board-level signals such as power-good indicators or fault flags while minimizing pin usage on the primary processor.

Key Specifications

Features POR
Interface I2C, SMBus
Output Type Push-Pull
Mounting Type Surface Mount
Number of I/O 16
Package / Case 24-WFQFN Exposed Pad
Clock Frequency 400 kHz
Interrupt Output Yes
Voltage - Supply 1.65V ~ 5.5V
Operating Temperature -40degC ~ 85degC
Supplier Device Package 24-HWQFN (4x4)
Current - Output Source/Sink 10mA, 25mA

Getting Started

To integrate this part, connect the SDA and SCL pins to your I2C host and configure the I2C address using the hardware address pins. On power-up, all channels default to inputs; use the I2C configuration register to switch pins to outputs as needed for your application.

Also Consider

MCP23017 MCHPMicrochip Technology - A popular 16-bit expander with high-speed I2C support up to 1.7 MHz and flexible interrupt configuration.