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Texas Instruments PCF8574ANG4 — Interface & Transceivers

Texas Instruments PCF8574ANG4 I²C I/O Expander, 8-Bit

MPNPCF8574ANG4
End of Life

Texas Instruments PCF8574ANG4, 8-bit I²C-bus I/O expander, 100 kHz clock, 2.5 V to 6 V supply, push-pull outputs, interrupt output, 16-PDIP package, -40°C to 85°C.

Texas Instruments PCF8574ANG4 datasheet (PDF)
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

PCF8574ANG4 specifications
ParameterValue
Output typePush-Pull
MountingThrough Hole
Supply voltage2.5V ~ 6V
Current - output source (Sink)1mA, 25mA
Clock frequency100 kHz
InterfaceI²C
Operating temperature-40°C~85°C
PackageTube
FeaturesPOR
Number of i (O)8
Case16-DIP (0.300\", 7.62mm)
Interrupt outputYes

Product details

8-bit I²C I/O expander for industrial and embedded systems

The part includes a power-on reset (POR) feature and an interrupt output that signals the host when input states change, reducing polling overhead.

Output drive and I²C bus considerations

The 1 mA source and 25 mA sink per pin set the practical load limits: direct LED drive is fine with a series resistor, but driving a relay coil or small solenoid needs an external transistor or MOSFET. The I²C interface runs at 100 kHz (standard mode), which is adequate for polling inputs or latching outputs at human-scale rates. The interrupt output (active-low, open-drain) lets the host sleep between events, saving power in battery-backed designs.

Package and mounting — through-hole for prototyping and legacy boards

Housed in a 16-pin PDIP (0.300" body width), the PCF8574ANG4 is through-hole mount, which simplifies hand-assembly, breadboarding, and rework. The DIP footprint is compatible with standard sockets, making it a practical choice for one-off builds, educational kits, or retrofitting older PCB designs that lack surface-mount pads.

Frequently asked questions

Is PCF8574ANG4 a direct replacement for PCF8574P?

The PCF8574ANG4 and PCF8574P are functionally identical — both are 8-bit I²C I/O expanders in a 16-pin DIP package with the same I²C address range (0x20–0x27). The suffix differences (NG4 vs P) typically indicate packaging or lead-free finish variants; they are pin-compatible and can be swapped in most designs. Always confirm the specific suffix with the datasheet for any subtle differences in ordering code.

Can PCF8574ANG4 be used with 3.3V logic?

Yes. The supply range is 2.5 V to 6 V, so 3.3 V operation is within spec. The I²C bus thresholds scale with VDD; at 3.3 V the logic-low and logic-high levels are compatible with standard 3.3 V MCUs. The 100 kHz I²C clock is also well within the margin for 3.3 V bus timing.