PCF8574WORD版.docVIP

INTEGRATED CIRCUITS DATA SHEET PCF8574 Remote 8-bit I/O expander for I2C-bus Product speci?cation Supersedes data of September 1994 File under Integrated Circuits, IC12  1997 Apr 02  Philips Semiconductors Remote 8-bit I/O expander for I2C-bus CONTENTS 1 FEATURES 2 GENERAL DESCRIPTION 3 ORDERING INFORMATION 4 BLOCK DIAGRAM 5 PINNING 6 CHARACTERISTICS OF THE I2C-BUS 6.1 Bit transfer 6.2 Start and stop conditions 6.3 System configuration 6.4 Acknowledge 7 FUNCTIONAL DESCRIPTION 7.1 Addressing 7.2 Interrupt 7.3 Quasi-bidirectional I/Os 8 LIMITING VALUES 9 HANDLING 10 DC CHARACTERISTICS 11 I2C-BUS TIMING CHARACTERISTICS 12 PACKAGE OUTLINES 13 SOLDERING 13.1 Introduction 13.2 DIP 13.2.1 Soldering by dipping or by wave 13.2.2 Repairing soldered joints 13.3 SO and SSOP 13.3.1 Reflow soldering 13.3.2 Wave soldering 13.3.3 Repairing soldered joints 14 DEFINITIONS 15 LIFE SUPPORT APPLICATIONS 16 PURCHASE OF PHILIPS I2C COMPONENTS 1997 Apr 02 2  Product speci?cation PCF8574  Philips Semiconductors Remote 8-bit I/O expander for I2C-bus 1 FEATURES  2 GENERAL DESCRIPTION  Product speci?cation PCF8574 ? Operating supply voltage 2.5 to 6 V ? Low standby current consumption of 10 ?A maximum ? I2C to parallel port expander ? Open-drain interrupt output ? 8-bit remote I/O port for the I2C-bus ? Compatible with most microcontrollers ? Latched outputs with high current drive capability for directly driving LEDs ? Address by 3 hardware address pins for use of up to 8 devices (up to 16 with PCF8574A) ? DIP16, or space-saving SO16 or SSOP20 packages. 3 ORDERING INFORMATION TYPE NUMBER The PCF8574 is a silicon CMOS circuit. It provides general purpose remote I/O expansion for most microcontroller families via the two-line bidirectional bus (I2C). The device consists of an 8-bit quasi-bidirectional port and an I2C-bus interface. The PCF8574 has a low current consumption and includes latched outputs with high current drive capability for directly driving LEDs. It also possesses an in