PCA9555 16-bit I2C SMBus I/O Expander

Texas Instruments Signal_Chain — specifications, applications, sourcing support and RFQ.

PCA9555 16-bit I2C SMBus I/O Expander

RFQ Available Sourcing Support Alternative Matching RoHS
Part Number
PCA9555
Manufacturer
Texas Instruments
Package
SSOP-24 DB 8.20 mm x 5.30 mm; SSOP-24 DBQ 8.65 mm x 3.90 mm; TVSOP-24 DGV 5.00 mm x 4.40 mm; SOIC-24 DW 15.4 mm x 7.50 mm; SSOP-24 PW 7.80 mm x 4.40 mm; VQFN-24 RGE 4.00 mm x 4.00 mm
Category
Signal Chain
Product Type
Operational Amplifier

Quick Sourcing Note

PCA9555 from Texas Instruments is a Signal_Chain 16-bit I2C SMBus I/O expander for remote I/O expansion through a fast I2C-compatible interface. It operates from 2.3 to 5.5 V over a -40 to 85 °C free-air temperature range and supports 400 kHz bus operation. The device provides 16 I/O bits, 5-V tolerant I/O ports, push-pull port outputs, and an open-drain active-low interrupt output. Three hardware address pins allow up to 8 devices. Package options include SSOP-24, TVSOP-24, SOIC-24, TSSOP-24, and VQFN-24 formats, with package-dependent junction-to-ambient thermal resistance values.

Specifications

TypeDescription
Part NumberPCA9555
ManufacturerTexas Instruments
Product TypeOperational Amplifier
CategorySignal Chain
Package CaseSSOP-24 DB 8.20 mm x 5.30 mm; SSOP-24 DBQ 8.65 mm x 3.90 mm; TVSOP-24 DGV 5.00 mm x 4.40 mm; SOIC-24 DW 15.4 mm x 7.50 mm; SSOP-24 PW 7.80 mm x 4.40 mm; VQFN-24 RGE 4.00 mm x 4.00 mm
Supply Voltage Operating Range2.3 to 5.5 V; recommended operating conditions
Supply Voltage Absolute Maximum-0.5 to 6 V; over operating free-air temperature range
Input Voltage Absolute Maximum-0.5 to 6 V; input negative-voltage rating may be exceeded if input current rating is observed
Output Voltage Absolute Maximum-0.5 to 6 V; output voltage rating may be exceeded if output current rating is observed
Input Clamp Current-20 mA; VI < 0
Output Clamp Current-20 mA; VO < 0
Input/Output Clamp Current+/-20 mA; VO < 0 or VO > VCC
Continuous Output Low Current50 mA; VO = 0 to VCC
Continuous Output High Current-50 mA; VO = 0 to VCC
Continuous Current Through GND-250 mA; absolute maximum ratings
Continuous Current Through VCC160 mA; absolute maximum ratings
Storage Temperature Range-65 to 150 °C; absolute maximum ratings
Operating Free-Air Temperature-40 to 85 °C; recommended operating conditions
High-Level Input Voltage0.7 x VCC to VCC; SCL, SDA
High-Level Input Voltage0.7 x VCC to 5.5 V; A2-A0, P07-P00, P17-P10
Low-Level Input Voltage-0.5 to 0.3 x VCC; SCL, SDA
Low-Level Input Voltage-0.5 to 0.3 x VCC; A2-A0, P07-P00, P17-P10
High-Level Output Current-10 mA; P07-P00, P17-P10
Low-Level Output Current25 mA; P07-P00, P17-P10
I2C Bus Frequency400 kHz; Fast I2C bus compatibility
Standby Current1 µA max; standby-current consumption
I/O Port Count16 bits; remote I/O expansion via I2C interface
Address Selection3 hardware address pins; up to 8 devices; A0, A1, A2 connected directly to VCC or ground
Default Power-On I/O ConfigurationInputs; at power on
Interrupt Output TypeOpen-drain active-low; INT pin; connect to VCC through pullup resistor
I/O Port Tolerance5-V tolerant; I/O ports
Port Output StructurePush-pull; P00-P07 and P10-P17 pins
HBM ESD Rating2000 V; human body model per ANSI/ESDA/JEDEC JS-001, all pins
CDM ESD Rating1000 V; charged device model per JESD22-C101 or ANSI/ESDA/JEDEC JS-002, all pins
Latch-Up PerformanceExceeds 100 mA; per JESD 78, Class II
Input Diode Clamp Voltage-1.2 V max; II = -18 mA, VCC = 2.3 V to 5.5 V
Thermal Resistance Junction-to-Ambient92.9 °C/W; DB SSOP-24 package
Thermal Resistance Junction-to-Ambient81.8 °C/W; DBQ QSOP-24 package
Thermal Resistance Junction-to-Ambient105.4 °C/W; DGV TVSOP-24 package
Thermal Resistance Junction-to-Ambient66.7 °C/W; DW SOIC-24 package
Thermal Resistance Junction-to-Ambient108.8 °C/W; PW TSSOP-24 package
Thermal Resistance Junction-to-Ambient48.4 °C/W; RGE QFN-24 package
Datasheet Statusrequest_only

Product Overview

The PCA9555 is a Texas Instruments 16-bit I2C SMBus I/O expander in the Signal_Chain category. It provides remote I/O expansion through an I2C-compatible interface with 400 kHz fast-bus compatibility. At power on, the I/O configuration defaults to inputs, and three hardware address pins support up to 8 devices when A0, A1, and A2 are connected directly to VCC or ground.

The device operates from a recommended 2.3 to 5.5 V supply across a -40 to 85 °C operating free-air temperature range. The I/O ports are 5-V tolerant, and P00-P07 and P10-P17 use push-pull output structures. Output drive ratings include -10 mA high-level output current and 25 mA low-level output current for the port pins. The INT output is open-drain active-low and is intended to connect to VCC through a pullup resistor.

Package options include SSOP-24 DB, SSOP-24 DBQ, TVSOP-24 DGV, SOIC-24 DW, SSOP-24 PW, and VQFN-24 RGE. Thermal resistance junction-to-ambient ranges from 48.4 °C/W for the RGE QFN-24 package to 108.8 °C/W for the PW TSSOP-24 package.

Key Features

  • 16-bit remote I/O expansion through I2C interface
  • 400 kHz fast I2C bus compatibility
  • 2.3 to 5.5 V recommended supply range
  • 1 µA maximum standby-current consumption
  • Three hardware address pins support up to 8 devices
  • Power-on default configures I/O ports as inputs
  • Open-drain active-low INT output with pullup resistor
  • 5-V tolerant I/O ports for port interface flexibility
  • Push-pull outputs on P00-P07 and P10-P17
  • -40 to 85 °C operating free-air temperature range

Typical Applications

  • Remote I/O expansion
  • I2C SMBus GPIO extension
  • Multi-device addressed I/O nodes
  • Interrupt-based input monitoring
  • 5-V tolerant port interfacing
  • Push-pull output control
  • Low-standby-current I/O expansion

Procurement Notes

When requesting a quote for PCA9555, buyers should confirm the manufacturer, package or case, required quantity, target date code, compliance documents, packing method, destination country and expected delivery schedule.

If alternatives are acceptable, buyers should share the approved vendor list, required electrical or optical limits, package constraints and qualification requirements. Any alternative part should be reviewed by the buyer's engineering team before production use.

For analog and signal-chain sourcing, supply voltage, bandwidth, accuracy, noise level, package, temperature grade, input/output configuration and qualification requirements should be verified before approval.

FAQ

What supply voltage range does the PCA9555 support?

The PCA9555 operates from a recommended 2.3 to 5.5 V supply range. Its absolute maximum supply voltage rating is -0.5 to 6 V over the operating free-air temperature range.

How many I/O ports are available on the PCA9555?

The PCA9555 provides 16 bits of remote I/O expansion through an I2C interface. At power on, the I/O configuration defaults to inputs.

What bus speed is specified for the PCA9555 interface?

The PCA9555 is specified for 400 kHz fast I2C bus compatibility. It is described as a 16-bit I2C SMBus I/O expander.

What package options are listed for the PCA9555?

Listed packages include SSOP-24 DB, SSOP-24 DBQ, TVSOP-24 DGV, SOIC-24 DW, SSOP-24 PW, and VQFN-24 RGE, with package dimensions provided for each option.

Technical Review & Sourcing Note

Prepared by LDeepAI Component Sourcing Team. Reviewed for RFQ, documentation and alternative sourcing use. Last updated: July 8, 2026.

This page is based on manufacturer datasheet information and LDeepAI sourcing review. Specifications should be verified against the official manufacturer datasheet before final procurement or design approval. Final electrical, optical and reliability approval should be confirmed by the buyer's engineering team.

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