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FEATURES

DB, DBQ, DGV, DW, OR PW PACKAGE

(TOP VIEW)

INT

A1

A2

P00

P01

P02

P03

P04

P05

P06

P07

GND

SDA

SCL

A0

P17

P16

P15

P14

P13

P12

P11

P10

1

2

3

4

5

6

7

8

9

10

11

12

24

23

22

21

20

19

18

17

16

15

14

13

24 23 22 21 20

7

8

9 10 11

1

2

3

4

5

6

18

17

16

15

14

13

RGE PACKAGE

(TOP VIEW)

19

12

P00

P01

P02

P03

P04

P05

A0

P17

P16

P15

P14

P13

DESCRIPTION/ORDERING INFORMATION

PCA9555

WITH INTERRUPT OUTPUT AND CONFIGURATION REGISTERS

• Low Standby-Current Consumption of

• Polarity Inversion Register

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µA Max

• Latched Outputs With High-Current Drive

Capability for Directly Driving LEDs

• Open-Drain Active-Low Interrupt Output

• Latch-Up Performance Exceeds 100 mA Per

JESD 78, Class II

• 5-V Tolerant I/O Ports

• ESD Protection Exceeds JESD 22

• Compatible With Most Microcontrollers

–

2000-V Human-Body Model (A114-A)

–

200-V Machine Model (A115-A)

• Address by Three Hardware Address Pins for

Use of up to Eight Devices

–

1000-V Charged-Device Model (C101)

(SCL), serial data (SDA)].

The PCA9555 consists of two 8-bit Configuration (input or output selection), Input Port, Output Port, and Polarity

Inversion (active high or active low operation) registers. At power on, the I/Os are configured as inputs. The

system master can enable the I/Os as either inputs or outputs by writing to the I/O configuration bits. The data for

each input or output is kept in the corresponding Input or Output register. The polarity of the Input Port register

can be inverted with the Polarity Inversion register. All registers can be read by the system master.

The system master can reset the PCA9555 in the event of a timeout or other improper operation by utilizing the

The PCA9555 open-drain interrupt (INT) output is activated when any input state differs from its corresponding

Input Port register state and is used to indicate to the system master that an input state has changed.

INT can be connected to the interrupt input of a microcontroller. By sending an interrupt signal on this line, the

remote I/O can inform the microcontroller if there is incoming data on its ports without having to communicate via

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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.

Copyright © 2005–2008, 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.