PCF8574/74A

Remote 8-bit I/O expander

The PCF8574/74A is a remote 8-bit i/o expander from NXP Semiconductors. View the full PCF8574/74A datasheet below including key specifications.

PCF8574/74A shares its datasheet with PCF8574, whose page lists every part number it covers.

Official PCF8574/74A datasheet (PDF) — the source this page was extracted from.

Manufacturer

NXP Semiconductors

PCF8574/74A Key Specifications

Parameter	Value
I/O bits	8 (quasi-bidirectional)
I2C-bus interface	100 kHz (Standard-mode)
Supply voltage range	2.5 V to 6 V
Standby current	2.5 μA (typical)
I/O weak pull-up current	100 μA
Total package sink capability	80 mA
Operating temperature range	-40 °C to +85 °C
Programmable slave addresses	8 for PCF8574 (0x20-0x27), 8 for PCF8574A (0x38-0x3F)

PCF8574/74A Overview

Part: PCF8574; PCF8574A

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

Description: The PCF8574/74A provides general-purpose remote 8-bit quasi-bidirectional I/O expansion via a 100 kHz I2C-bus, featuring three hardware address inputs, an active LOW interrupt output, and operating from 2.5 V to 6 V with a typical standby current of 2.5 μA.

Operating Conditions:

Supply voltage: 2.5 V to 6 V
Operating temperature: -40 °C to +85 °C
I2C-bus frequency: 100 kHz

Absolute Maximum Ratings:

Max supply voltage: null
Max continuous current: 80 mA (total package sink capability)
Max junction/storage temperature: null

Key Specs:

I/O bits: 8 (quasi-bidirectional)
I2C-bus interface: 100 kHz (Standard-mode)
Supply voltage range: 2.5 V to 6 V
Standby current: 2.5 μA (typical)
I/O weak pull-up current: 100 μA
Total package sink capability: 80 mA
Operating temperature range: -40 °C to +85 °C
Programmable slave addresses: 8 for PCF8574 (0x20-0x27), 8 for PCF8574A (0x38-0x3F)

Features:

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 μA 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 μA typical)
-40 °C to +85 °C operation
ESD protection exceeds 2000 V HBM per JESD22-A114 and 1000 V CDM per JESD22-C101
Latch-up testing is done to JEDEC standard JESD78 which exceeds 100 mA

Applications:

LED signs and displays
Servers
Key pads
Industrial control
Medical equipment
PLC
Cellular telephones
Mobile devices
Gaming machines
Instrumentation and test measurement

Package:

DIP16 (16 leads (300 mil))
SO16 (16 leads; body width 7.5 mm)
SSOP20 (20 leads; body width 4.4 mm)

PCF8574/74A Features

I 2 C-bus to parallel port expander
100 kHz I 2 C-bus interface (Standard-mode I 2 C-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
ESD protection exceeds 2000 V HBM per JESD22-A114 and 1000 V CDM per JESD22-C101

Product data sheet

Latch-up testing is done to JEDEC standard JESD78 which exceeds 100 mA
Packages offered: DIP16, SO16, SSOP20

PCF8574/74A Applications

LED signs and displays
Servers
Key pads
Industrial control
Medical equipment
PLC
Cellular telephones
Mobile devices
Gaming machines
Instrumentation and test measurement

PCF8574/74A Pin Configuration

Table 3. Pin description

Symbol	Pin	Pin	Description
Symbol	DIP16, SO16	SSOP20	Description
A0	1	6	address input 0
A1	2	7	address input 1
A2	3	9	address input 2
P0	4	10	quasi-bidirectional I/O 0
P1	5	11	quasi-bidirectional I/O 1
P2	6	12	quasi-bidirectional I/O 2
P3	7	14	quasi-bidirectional I/O 3
V SS	8	15	supply ground
P4	9	16	quasi-bidirectional I/O 4
P5	10	17	quasi-bidirectional I/O 5
P6	11	19	quasi-bidirectional I/O 6
P7	12	20	quasi-bidirectional I/O 7
INT	13	1	interrupt output (active LOW)
SCL	14	2	serial clock line
SDA	15	4	serial data line
V DD	16	5	supply voltage
n.c.	-	3, 8, 13, 18	not connected

PCF8574/74A Thermal Information

Table 8.	Thermal characteristics	Thermal characteristics	Thermal characteristics	Thermal characteristics
Symbol	Parameter	Conditions	Typ	Unit
R th(j-a)	thermal resistance from junction to ambient	SO16 package	115	C/W
		SSOP20 package	136	C/W

PCF8574/74A Package Information

DIP16: plastic dual in-line package; 16 leads (300 mil)

SOT38-4

DIMENSIONS (inch dimensions are derived from the original mm dimensions)

UNIT	A max.	1 A min.	2 A max.	b	b 1	b 2	c	(1) D	(1) E	e	e 1	L	M E	M H	w	(1) Z max.
mm	4.2	0.51	3.2	1.73 1.30	0.53 0.38	1.25 0.85	0.36 0.23	19.50 18.55	6.48 6.20	2.54	7.62	3.60 3.05	8.25 7.80	10.0 8.3	0.254	0.76
inches	0.17	0.02	0.13	0.068 0.051	0.021 0.015	0.049 0.033	0.014 0.009	0.77 0.73	0.26 0.24	0.1	0.3	0.14 0.12	0.32 0.31	0.39 0.33	0.01	0.03

More datasheets

All NXP Semiconductors datasheets (189)

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