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    Parts    PCF8574DWR
PCF8574DWR

TIPCF8574DWR

Texas Instruments
I/O Expander 8 I2C 100 kHz 16-SOIC
Active11,603 in stock
Datasheet Digi-Key Mouser Compare Prices

Overview

The PCF8574DWR is an 8-bit remote I/O expander designed for the two-line bidirectional bus (I2C) and operates across a 2.5V to 6V supply range. It provides general-purpose I/O expansion via the I2C interface and includes an open-drain interrupt output to notify the host processor of input state changes.

Why Choose This Part

The device features a low standby current consumption of 10uA and latched outputs with high-current drive capability. Its open-drain interrupt output simplifies system design by eliminating the need for constant polling over the I2C bus.

Applications

LED Status Indicators
Utilizes the high-current sink capability (up to 25mA) to directly drive multiple LEDs from the I2C bus without external transistors.
Keypad Scanning
The 8-bit quasi-bidirectional I/Os and interrupt pin allow for efficient monitoring of button matrices while minimizing microcontroller pin usage.
Server and Telecom Management
Used in system monitoring for filter units and switching equipment to control low-speed signals and status registers.

Key Specifications

Features POR
Interface I2C
Output Type Push-Pull
Mounting Type Surface Mount
Number of I/O 8
Package / Case 16-SOIC (0.295", 7.50mm Width)
Clock Frequency 100 kHz
Interrupt Output Yes
Voltage - Supply 2.5V ~ 6V
Operating Temperature -40degC ~ 85degC
Supplier Device Package 16-SOIC
Current - Output Source/Sink 1mA, 25mA

Getting Started

To implement this device, connect the SDA and SCL lines to your I2C master with appropriate pull-up resistors and set the hardware address using the A0-A2 pins. Software integration can be achieved using standard I2C libraries by writing a single byte to configure the quasi-bidirectional ports.

PCF8574 Family

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

Part Number Package Stock
PCF8574DWR (this part) SOIC-16 11,603
PCF8574ADWR SOIC-16 11,390
PCF8574AN DIP-16 3,770
PCF8574RGTR Tape & Reel VFQFN-16 —
PCF8574DGVR TFSOP-20 —
PCF8574ADW SOIC-16 1,595
Also available as: PCF8574PWR

Also Consider

PCF8575DWR TITexas Instruments - Provides 16 bits of I/O expansion instead of 8 bits for higher density requirements in a similar SOIC package.