DESCRIPTION/ORDERING INFORMATION (CONTINUED)

PCF8574

The PCF8574 provides an open-drain output (INT) that can be connected to the interrupt input of a

microcontroller. An interrupt is generated by any rising or falling edge of the port inputs in the input mode. After

to the original setting or data is read from, or written to, the port that generated the interrupt. Resetting occurs in

the read mode at the acknowledge bit after the rising edge of the SCL signal, or in the write mode at the

acknowledge bit after the high-to-low transition of the SCL signal. Interrupts that occur during the acknowledge

clock pulse can be lost (or be very short) due to the resetting of the interrupt during this pulse. Each change of

the I/Os after resetting is detected and, after the next rising clock edge, is transmitted as INT. Reading from, or

writing to, another device does not affect the interrupt circuit.

By sending an interrupt signal on this line, the remote I/O can inform the microcontroller if there is incoming data

device.

ORDERING INFORMATION

ORDERABLE PART NUMBER

TOP-SIDE MARKING

PCF8574N

PDIP – N

Tube of 25

PCF8574N

PCF8574NE4

QFN – RGT

Reel of 3000

PCF8574RGTR

ZWJ

PCF8574RGYR

QFN – RGY

Reel of 1000

PF574

PCF8574RGYRG4

PCF8574DW

Tube of 40

PCF8574DWE4

SOIC – DW

PCF8574

–40

°C to 85°C

PCF8574DWR

Reel of 2000

PCF8574DWRE4

PCF8574PW

Tube of 70

PCF8574PWE4

TSSOP – PW

PF574

PCF8574PWR

Reel of 2000

PCF8574PWRE4

PCF8574DGVR

TVSOP – DGV

Reel of 2000

PF574

PCF8574DGVRE4

(1)

Package drawings, thermal data, and symbolization are available at www.ti.com/packaging.

(2)

For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI

website at www.ti.com.

2

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Product Folder Link(s): PCF8574