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PCA9555

ACTIVE

16-bit 2.3- to 5.5-V I2C/SMBus I/O expander with interrupt, weak pull-up & config registers

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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 Performance enhancements for power-on reset, interrupt, and lower voltage operation.

Product details

Number of I/Os 16 Features Configuration registers, Interrupt pin Supply voltage (min) (V) 2.3 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) 2.3 Supply voltage (max) (V) 5.5 Addresses 8 Rating Catalog Frequency (max) (MHz) 0.4 Operating temperature range (°C) -40 to 85
SOIC (DW) 24 159.65 mm² 15.5 x 10.3 SSOP (DB) 24 63.96 mm² 8.2 x 7.8 SSOP (DBQ) 24 51.9 mm² 8.65 x 6 TSSOP (PW) 24 49.92 mm² 7.8 x 6.4 TVSOP (DGV) 24 32 mm² 5 x 6.4 VQFN (RGE) 24 16 mm² 4 x 4
  • Low Standby-Current Consumption of 1 µA Max
  • 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
  • Address by Three Hardware Address Pins for Use of up to Eight Devices
  • 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)
    • 200-V Machine Model (A115-A)
    • 1000-V Charged-Device Model (C101)
  • Low Standby-Current Consumption of 1 µA Max
  • 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
  • Address by Three Hardware Address Pins for Use of up to Eight Devices
  • 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)
    • 200-V Machine Model (A115-A)
    • 1000-V Charged-Device Model (C101)

This 16-bit I/O expander for the two-line bidirectional bus (I2C) is designed for 2.3-V to 5.5-V VCC operation. It provides general-purpose remote I/O expansion for most microcontroller families via the I2C interface [serial clock (SCL), serial data (SDA)].

The PCA9555 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. All registers can be read by the system master.

This 16-bit I/O expander for the two-line bidirectional bus (I2C) is designed for 2.3-V to 5.5-V VCC operation. It provides general-purpose remote I/O expansion for most microcontroller families via the I2C interface [serial clock (SCL), serial data (SDA)].

The PCA9555 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. All registers can be read by the system master.

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Technical documentation

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Type Title Date
* Data sheet PCA9555 Remote 16-bit I2C and SMBus I/O Expander with Interrupt Output and Configuration Registers datasheet (Rev. J) PDF | HTML 11 Mar 2021
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
Selection guide Logic Guide (Rev. AB) 12 Jun 2017
Application note Choosing the Correct I2C Device for New Designs PDF | HTML 07 Sep 2016
Application note Understanding and Interpreting Standard-Logic Data Sheets (Rev. C) 02 Dec 2015
Application note Understanding the I2C Bus PDF | HTML 30 Jun 2015
Application note I2C Bus Pull-Up Resistor Calculation PDF | HTML 13 Feb 2015
Application note Programming Fun Lights With TI's TCA6507 30 Nov 2007
Application note Semiconductor Packing Material Electrostatic Discharge (ESD) Protection 08 Jul 2004

Design & development

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Simulation model

PCA9555 IBIS Model

SCPM035.ZIP (98 KB) - IBIS Model
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User guide: PDF
Package Pins CAD symbols, footprints & 3D models
SOIC (DW) 24 Ultra Librarian
SSOP (DB) 24 Ultra Librarian
SSOP (DBQ) 24 Ultra Librarian
TSSOP (PW) 24 Ultra Librarian
TVSOP (DGV) 24 Ultra Librarian
VQFN (RGE) 24 Ultra Librarian

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