PCA8574/PCA8574A Remote 8-bit I/O Expander For I2C-bus With Interrupt

The PCA8574 PCA8574A provide general purpose remote I/O expansion for most Microcontroller families via the two-line bidirectional I2C-bus (serial Clock (SCL), serial data (SDA)). The devices consist of an 8-bit quasi-bidirectional port and an I2C-bus Interface The PCA8574 PCA8574A have low current consumption and include latched outputs with 25 mA high current drive capability for directly driving LEDs The PCA8574 PCA8574A also possess an interrupt line (INT) that 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. The internal Power-On Reset (POR) initializes the I/Os as inputs.
By NXP Semiconductors