深圳市中立信电子科技有限公司

PCF8574T/3,518

Remote 8-bit I/O expander for I2C-bus with interrupt

接口-I/O扩展器 I/O EXPANDER I2C

General description PCF8574T/3,518

The PCF8574/74A provides general-purpose remote I/O expansion via the two-wire

bidirectional I2C-bus (serial clock (SCL), serial data (SDA)).

The devices consist of eight quasi-bidirectional ports, 100 kHz I2C-bus interface, three

hardware address inputs and interrupt output operating between 2.5 V and 6 V. The

quasi-bidirectional port can be independently assigned as an input to monitor interrupt

status or keypads, or as an output to activate indicator devices such as LEDs. System

master can read from the input port or write to the output port through a single register.

Features and benefits PCF8574T/3,518

 I2C-bus to parallel port expander

 100 kHz I2C-bus interface (Standard-mode I2C-bus)

 Operating supply voltage 2.5 V to 6 V with non-overvoltage tolerant I/O held to VDD

with 100 A current source

 8-bit remote I/O pins that default to inputs at power-up

 Latched outputs directly drive LEDs

 Total package sink capability of 80 mA

 Active LOW open-drain interrupt output

 Eight programmable slave addresses using three address pins

 Low standby current (2.5 A typical)

 40 C to +85 C operation

Applications PCF8574T/3,518

 LED signs and displays

 Servers

 Key pads

 Industrial control

 Medical equipment

 PLC

 Cellular telephones

 Mobile devices

 Gaming machines

 Instrumentation and test measurement