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PCF8574A_05 Datasheet, PDF (1/21 Pages) Texas Instruments – REMOTE 8-BIT I/O EXPANDER FOR I2C BUS
www.ti.com
FEATURES
• Low Standby-Current Consumption of
10 µA Max
• I2C to Parallel-Port Expander
• Open-Drain Interrupt Output
DW OR N PACKAGE
(TOP VIEW)
PCF8574A
REMOTE 8-BIT I/O EXPANDER FOR I2C BUS
SCPS069D – JULY 2001 – REVISED OCTOBER 2005
• Compatible With Most Microcontrollers
• Latched Outputs With High-Current Drive
Capability for Directly Driving LEDs
• Latch-Up Performance Exceeds 100 mA Per
JESD 78, Class II
RGY PACKAGE
(TOP VIEW)
DGV OR PW PACKAGE
(TOP VIEW)
A0 1
A1 2
A2 3
P0 4
P1 5
P2 6
P3 7
GND 8
16 VCC
15 SDA
14 SCL
13 INT
12 P7
11 P6
10 P5
9 P4
1
SCL 2
NC 3
SDA 4
VCC 5
A0 6
A1 7
NC 8
A2 9
10
20
19 P6
18 NC
17 P5
16 P4
15 GND
14 P3
13 NC
12 P2
11
NC − No internal connection
INT 1
SCL 2
NC 3
SDA 4
VCC 5
A0 6
A1 7
NC 8
A2 9
P0 10
20 P7
19 P6
18 NC
17 P5
16 P4
15 GND
14 P3
13 NC
12 P2
11 P1
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.
TA
–40°C to 85°C
ORDERING INFORMATION
PACKAGE (1)
ORDERABLE PART NUMBER
QFN – RGY
Tape and reel
PCF8574ARGYR
PDIP – N
Tube
PCF8574AN
SOIC – DW
Tube
Tape and reel
PCF8574ADW
PCF8574ADWR
TSSOP – PW
Tape and reel
PCF8574APWR
TVSOP – DGV
Tape and reel
PCF8574ADGVR
TOP-SIDE MARKING
PF574A
PCF8574AN
PCF8574A
PF574A
PF574A
(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.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2001–2005, Texas Instruments Incorporated