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TCA9555

ACTIVE

16-bit 1.65- to 5.5-V I2C/SMBus I/O expander with interrupt, weak pull-up & config registers

Product details

Number of I/Os 16 Features Configuration registers, Interrupt pin Supply voltage (min) (V) 1.65 Supply voltage (max) (V) 5.5 Addresses 8 Rating Catalog Frequency (max) (MHz) 0.4 Operating temperature range (°C) -40 to 85
Number of I/Os 16 Features Configuration registers, Interrupt pin Supply voltage (min) (V) 1.65 Supply voltage (max) (V) 5.5 Addresses 8 Rating Catalog Frequency (max) (MHz) 0.4 Operating temperature range (°C) -40 to 85
SSOP (DB) 24 63.96 mm² 8.2 x 7.8 TSSOP (PW) 24 49.92 mm² 7.8 x 6.4 VQFN (RGE) 24 16 mm² 4 x 4 WQFN (RTW) 24 16 mm² 4 x 4
  • Low Standby-Current Consumption of 3.5 µA Maximum
  • I2C to Parallel Port Expander
  • Open-Drain Active-Low Interrupt Output
  • 5-V Tolerant I/O Ports
  • Compatible With Most Microcontrollers
  • 400-kHz Fast I2C Bus
  • Configurable Slave Address with 3 Address Pins
  • Polarity Inversion Register
  • Latched Outputs With High-Current Drive Capability for Directly Driving LEDs
  • Latch-Up Performance Exceeds 100 mA Per JESD 78, Class II
  • ESD Protection Exceeds JESD 22
    • 2000-V Human-Body Model (A114-A)
    • 1000-V Charged-Device Model (C101)
  • Low Standby-Current Consumption of 3.5 µA Maximum
  • I2C to Parallel Port Expander
  • Open-Drain Active-Low Interrupt Output
  • 5-V Tolerant I/O Ports
  • Compatible With Most Microcontrollers
  • 400-kHz Fast I2C Bus
  • Configurable Slave Address with 3 Address Pins
  • Polarity Inversion Register
  • Latched Outputs With High-Current Drive Capability for Directly Driving LEDs
  • Latch-Up Performance Exceeds 100 mA Per JESD 78, Class II
  • ESD Protection Exceeds JESD 22
    • 2000-V Human-Body Model (A114-A)
    • 1000-V Charged-Device Model (C101)

This 16-bit I/O expander for the two-line bidirectional bus (I2C) is designed for 1.65-V to 5.5-V VCC operation. It provides general-purpose remote I/O expansion for most microcontroller families via the I2C interface.

The TCA9555 consists of two 8-bit Configuration (input or output selection), Input Port, Output Port, and Polarity Inversion (active high or active low operation) registers. At power on, the I/Os are configured as inputs. The system master can enable the I/Os as either inputs or outputs by writing to the I/O configuration bits. The data for each input or output is kept in the corresponding Input or Output register. The polarity of the Input Port register can be inverted with the Polarity Inversion register.

The TCA9555 is identical to the TCA9535, except for the inclusion of the internal I/O pull-up resistor, which pulls the I/O to a default high when configured as an input and undriven.

Three hardware pins (A0, A1, and A2) are used to program the I2C address, which allows up to eight TCA9555 devices to share the same I2C bus or SMBus. The fixed I2C address of the TCA9555 is the same as the PCF8575, PCF8575C, and PCF8574, allowing up to eight of these devices in any combination to share the same I2C bus or SMBus.

This 16-bit I/O expander for the two-line bidirectional bus (I2C) is designed for 1.65-V to 5.5-V VCC operation. It provides general-purpose remote I/O expansion for most microcontroller families via the I2C interface.

The TCA9555 consists of two 8-bit Configuration (input or output selection), Input Port, Output Port, and Polarity Inversion (active high or active low operation) registers. At power on, the I/Os are configured as inputs. The system master can enable the I/Os as either inputs or outputs by writing to the I/O configuration bits. The data for each input or output is kept in the corresponding Input or Output register. The polarity of the Input Port register can be inverted with the Polarity Inversion register.

The TCA9555 is identical to the TCA9535, except for the inclusion of the internal I/O pull-up resistor, which pulls the I/O to a default high when configured as an input and undriven.

Three hardware pins (A0, A1, and A2) are used to program the I2C address, which allows up to eight TCA9555 devices to share the same I2C bus or SMBus. The fixed I2C address of the TCA9555 is the same as the PCF8575, PCF8575C, and PCF8574, allowing up to eight of these devices in any combination to share the same I2C bus or SMBus.

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Technical documentation

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Type Title Date
* Data sheet TCA9555 Low-Voltage 16-Bit I2C and SMBus I/O Expander with Interrupt Output and Configuration Registers datasheet (Rev. E) PDF | HTML 01 Apr 2019
Application note How to Configure an I2C Push-Pull IO Expander to Operate as Open Drain PDF | HTML 17 Jul 2024
Application note I2C: What is the Auto Increment Feature? PDF | HTML 05 Jul 2024
Application note Understanding Transient Drive Strength vs. DC Drive Strength in Level-Shifters (Rev. A) PDF | HTML 03 Jul 2024
Application note I2C Dynamic Addressing 25 Apr 2019
Application note Choosing the Correct I2C Device for New Designs PDF | HTML 07 Sep 2016
Application note Understanding the I2C Bus PDF | HTML 30 Jun 2015
Application note I2C Bus Pull-Up Resistor Calculation PDF | HTML 13 Feb 2015
EVM User's guide I/O Expander EVM User's Guide (Rev. A) 25 Jul 2014

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Evaluation board

IO-EXPANDER-EVM — IO-EXPANDER-EVM: I2C and SMBus IO Expander Evaluation Module

The IO expander evaluation module (EVM) lets you evaluate TI's portfolio of SMBus and I2C IO expander line devices. The TCA6424A and TCA9539 come installed on the board. The 24-pin TSSOP footprint also supports TCA6408A, TCA6416A, TCA9534, TCA9534ATCA9535, TCA9538, TCA9554, TCA9554A and TCA9555.

User guide: PDF
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Firmware

SLVC564 I/O Expander Software and Firmware Package

Supported products & hardware

Supported products & hardware

Products
I2C general-purpose I/Os (GPIOs)
TCA6408A 8-bit translating 1.65- to 5.5-V I2C/SMBus I/O expander with interrupt, reset & config registers TCA6408A-Q1 Automotive 8-bit translating I2C/SMBus I/O expander with interrupt, reset & config registers TCA6416A 16-bit translating 1.65- to 5.5-V I2C/SMBus I/O expander with interrupt, reset & config registers TCA6424A 24-bit translating 1.65- to 5.5-V I2C/SMBus I/O expander with interrupt, reset & config registers TCA9534 8-bit 1.65- to 5.5-V I2C/SMBus I/O expander with interrupt & config registers TCA9534A 8-bit 1.65- to 5.5-V I2C/SMBus I/O expander with interrupt, & config registers TCA9535 16-bit 1.65- to 5.5-V I2C/SMBus I/O expander with interrupt & config registers TCA9538 8-bit 1.65- to 5.5-V I2C/SMBus I/O expander with interrupt, reset & config registers TCA9539 16-bit 1.65- to 5.5-V I2C/SMBus I/O expander with interrupt, reset & config registers TCA9554 8-bit 1.65- to 5.5-V I2C/SMBus I/O expander with interrupt, weak pull-up & config registers TCA9554A 8-bit 1.65- to 5.5-V I2C/SMBus I/O expander with interrupt, weak pull-up & config registers TCA9555 16-bit 1.65- to 5.5-V I2C/SMBus I/O expander with interrupt, weak pull-up & config registers
Hardware development
Evaluation board
IO-EXPANDER-EVM IO-EXPANDER-EVM: I2C and SMBus IO Expander Evaluation Module
Simulation model

TCA9555 IBIS Model

SCPM041.ZIP (86 KB) - IBIS Model
Design tool

I2C-DESIGNER — I2C designer tool

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Simulation tool

PSPICE-FOR-TI — PSpice® for TI design and simulation tool

PSpice® for TI is a design and simulation environment that helps evaluate functionality of analog circuits. This full-featured, design and simulation suite uses an analog analysis engine from Cadence®. Available at no cost, PSpice for TI includes one of the largest model libraries in the (...)
Simulation tool

TINA-TI — SPICE-based analog simulation program

TINA-TI provides all the conventional DC, transient and frequency domain analysis of SPICE and much more. TINA has extensive post-processing capability that allows you to format results the way you want them. Virtual instruments allow you to select input waveforms and probe circuit nodes voltages (...)
User guide: PDF
Package Pins CAD symbols, footprints & 3D models
SSOP (DB) 24 Ultra Librarian
TSSOP (PW) 24 Ultra Librarian
VQFN (RGE) 24 Ultra Librarian
WQFN (RTW) 24 Ultra Librarian

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Information included:
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  • Assembly location

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