PCF8574AT Integrated Circuit IC Chip Remote 8- Bit I/O Expander For I2C- Bus Open Drain Interrupt Output

PCF8574AT Remote 8-bit I/O expander for I2C-bus

PCF8574 Series GENERAL DESCRIPTION

The PCF8574 is a silicon CMOS circuit. It provides general

purpose remote I/O expansion for most microcontroller

families via the two-line bidirectional bus (I2C).

The device consists of an 8-bit quasi-bidirectional port and

an I2C-bus interface. The PCF8574 has a low current

consumption and includes latched outputs with high

current drive capability for directly driving LEDs. It also

possesses an interrupt line (INT) which can be connected

to the interrupt logic of the 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 the I2C-bus. This means that

the PCF8574 can remain a simple slave device.

The PCF8574 and PCF8574A versions differ only in their

slave address as shown in Fig.9.

FEATURES

• Operating supply voltage 2.5 to 6 V

• Low standby current consumption of 10 µA maximum

• I2C to parallel port expander

• Open-drain interrupt output

• 8-bit remote I/O port for the I2C-bus

• Compatible with most microcontrollers

• Latched outputs with high current drive capability for

directly driving LEDs

• Address by 3 hardware address pins for use of up to

8 devices (up to 16 with PCF8574A)

• DIP16, or space-saving SO16 or SSOP20 packages.

Product Attributes