PCF8574_08 Datasheet, PDF (1/26 Pages) Texas Instruments – REMOTE 8-BIT I/O EXPANDER FOR I2C BUS

PCF8574
www.ti.com ............................................................................................................................................................... SCPS068G – JULY 2001 – REVISED MAY 2008
REMOTE 8-BIT I/O EXPANDER FOR I²C BUS
FEATURES
1
• Low Standby-Current Consumption of
10 µA Max
• I²C to Parallel-Port Expander
• Open-Drain Interrupt Output
DW OR N PACKAGE
(TOP VIEW)
A0 1
A1 2
A2 3
P0 4
P1 5
P2 6
P3 7
GND 8
16 V_CC
15 SDA
14 SCL
13 INT
12 P7
11 P6
10 P5
9 P4
RGT PACKAGE
(TOP VIEW)
V_CC 1
A0 2
A1 3
A2 4
12 P6
11 P5
10 P4
9 GND
• 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)
1
SCL 2
NC 3
SDA 4
V_CC 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
INT ¹
SCL ²
NC ³
SDA ⁴
V_CC 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
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 V_CC
operation.
The PCF8574 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 V_CC is
active. An additional strong pullup to V_CC 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.
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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 © 2001–2008, Texas Instruments Incorporated