NXP PCF8574T/3,518 I/O Expander

The NXP PCF8574T/3,518 is a robust I/O expander that offers an optimal solution for expanding the input/output capabilities of microcontrollers with a limited number of pins. This versatile chip uses the I²C-bus interface, which is a widely adopted protocol, allowing for easy integration into a vast array of embedded systems and IoT devices.

With the PCF8574T/3,518, designers can significantly increase the number of I/O ports using just two pins from the microcontroller for the I²C bus. This feature is particularly beneficial for applications where PCB space is at a premium, or when using microcontrollers with fewer pins, without the need to move to a larger microcontroller with more pins.

Key Features:

• Expandability: The device provides an additional 8 I/O ports, which can be configured as inputs or outputs.
• Serial Interface: Utilizes the I²C-bus interface, allowing for serial communication over just two wires (SDA and SCL), and supports a wide range of bus speeds.
• Addressing: Offers three hardware address pins that allow up to eight devices to share the same I²C bus, enabling a total of 64 I/O ports.
• Interrupt Output: Features an interrupt output that can be connected to the interrupt logic of the microcontroller. This allows the microcontroller to be informed of input changes without the need to constantly poll the expander.
• Operating Voltage: Supports a supply voltage range of 2.5V to 6V, making it suitable for both 5V and 3.3V systems.
• Package: Comes in a space-saving SO16 package, which is ideal for compact designs.

Applications:

The PCF8574T/3,518 is designed for a multitude of applications across various industries. It is particularly well-suited for:

• Server motherboards
• Embedded systems
• Industrial control systems
• Home automation
• Consumer electronics

Overall, the NXP PCF8574T/3,518 I/O expander is a highly efficient solution for system designers looking to increase the I/O capabilities of microcontroller-based systems without incurring significant additional costs or sacrificing valuable board space.