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TCA9555RTWR

TITCA9555RTWR

Texas Instruments
Interface - I/O Expanders Remote 16B I2C & SMB us I/O Expander
2,030 in stock
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Overview

The TCA9555RTWR is a 16-bit general-purpose I/O expander designed for I2C and SMBus applications. It provides a simple solution when additional I/O is needed for microcontrollers, offering a wide operating voltage range from 1.65V to 5.5V and an integrated interrupt output to signal the host processor of input state changes.

Why Choose This Part

This device features a polarity inversion register, allowing engineers to configure active-high or active-low logic in software. It includes high-current drive capability for LEDs and supports up to eight unique I2C addresses via three hardware address pins, enabling up to 128 I/O pins on a single bus.

Applications

LED Driving
Utilizing the high-current drive capability of 25mA per channel to directly drive status LEDs without external transistors.
Push-Button Monitoring
Scanning keypads or monitoring momentary switches using the interrupt output to wake the host MCU only when a press is detected.
System Configuration Strapping
Reading hardware version jumpers or DIP switches to free up primary microcontroller GPIOs during the boot sequence.
Level Shifting I/O
Interfacing between a low-voltage processor and higher-voltage peripherals by utilizing the wide VDD supply range.

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-WQFN (4x4)
Current - Output Source/Sink 10mA, 25mA

Getting Started

To implement this part, connect the SDA and SCL pins to the I2C bus with appropriate pull-up resistors and set the A0, A1, and A2 pins to define the slave address. Use the interrupt pin (INT) connected to an MCU GPIO to handle asynchronous input changes without constant polling. For prototyping, TI provides several TCA9555 evaluation modules that are compatible with standard breadboards.

TCA9555 Family

Comparing specs that differ across variants. The current part is highlighted.

Part Number Package Stock
TCA9555RTWR (this part) WFQFN-24 2,030
TCA9555PWR TSSOP-24 11,546
TCA9555DBR SSOP-24 1,247
Also available as: TCA9555RGER

Also Consider

MCP23017 MCHPMicrochip Technology - Common 16-bit I2C alternative featuring internal pull-up resistors and a higher 1.7 MHz bus speed in some modes.

Categories

Interface ICs > I/O Expanders