PCF8574A
REMOTE 8-BIT I/O EXPANDER FOR I2C BUS
www.ti.com
SCPS069D–JULY 2001–REVISED OCTOBER 2005
FEATURES
•
Low Standby-Current Consumption of
10 µA Max
I2C to Parallel-Port Expander
•
•
Compatible With Most Microcontrollers
Latched Outputs With High-Current Drive
Capability for Directly Driving LEDs
•
•
Open-Drain Interrupt Output
•
Latch-Up Performance Exceeds 100 mA Per
JESD 78, Class II
RGY PACKAGE
(TOP VIEW)
DGV OR PW PACKAGE
(TOP VIEW)
DW OR N PACKAGE
(TOP VIEW)
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
V
SDA
A0
A1
1
2
3
4
5
6
7
8
16
15
INT
SCL
NC
P7
P6
CC
1
20
19
18
17
16
15
14
13
12
2
3
4
5
6
7
8
9
SCL
NC
SDA
P6
NC
P5
P4
GND
P3
14 SCL
A2
P0
P1
P2
NC
P5
P4
GND
P3
INT
P7
P6
P5
P4
13
12
11
10
9
SDA
V
CC
V
CC
A0
A1
NC
A2
P0
A0
A1
NC
A2
P3
GND
NC
P2
P1
NC
P2
10
11
NC − No internal connection
NC − No internal connection
DESCRIPTION/ORDERING INFORMATION
This 8-bit input/output (I/O) expander for the two-line bidirectional bus (I2C) is designed for 2.5-V to 6-V VCC
operation.
The PCF8574A provides general-purpose remote I/O expansion for most microcontroller families via the I2C
interface [serial clock (SCL), serial data (SDA)].
The device features an 8-bit quasi-bidirectional I/O port (P0–P7), including latched outputs with high-current drive
capability for directly driving LEDs. Each quasi-bidirectional I/O can be used as an input or output without the use
of a data-direction control signal. At power on, the I/Os are high. In this mode, only a current source to VCC is
active. An additional strong pullup to VCC allows fast rising edges into heavily loaded outputs. This device turns
on when an output is written high and is switched off by the negative edge of SCL. The I/Os should be high
before being used as inputs.
ORDERING INFORMATION
TA
PACKAGE(1)
ORDERABLE PART NUMBER
PCF8574ARGYR
PCF8574AN
TOP-SIDE MARKING
PF574A
QFN – RGY
PDIP – N
Tape and reel
Tube
PCF8574AN
Tube
PCF8574ADW
–40°C to 85°C
SOIC – DW
PCF8574A
Tape and reel
Tape and reel
Tape and reel
PCF8574ADWR
TSSOP – PW
TVSOP – DGV
PCF8574APWR
PF574A
PF574A
PCF8574ADGVR
(1) Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Copyright © 2001–2005, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.