MICROCHIP 16-Bit I/O Expander IC, SSOP-28, I2C Interface

The MICROCHIP 16-Bit I/O Expander provides a versatile remote bidirectional I/O port solution for microcontroller and system designs requiring additional input/output pins. It communicates via a fast I2C serial interface with a clock frequency of up to 1.7MHz, facilitating efficient data transfer and easy integration into digital circuits.

All 16 I/O pins default to an input state upon power-up, enhancing system safety. The device features three hardware address pins, allowing up to eight identical devices to share the same I2C bus without address conflicts. Each I/O pin can be individually configured as an input or output, and the output drivers can be set as active-high, active-low, or open-drain to match different logic level requirements and drive external components.

Advanced interrupt management is a key feature. The chip includes two independent interrupt outputs, INTA and INTB, which can be configured to operate separately or be logically combined. An interrupt-on-change capability can be triggered by pin state changes or deviations from pre-configured default register values, reducing the need for constant microcontroller polling. A polarity inversion register allows the logical polarity of the input port data to be inverted, simplifying interface design with active-low signals.

Designed for robust operation, it includes an external reset input for reliable system initialisation and consumes a very low standby current of just 1µA (maximum), making it suitable for power-sensitive applications. It operates from a wide voltage range of 1.8V to 5.5V and across an extensive industrial temperature range from -40°C to +85°C, ensuring reliable performance in diverse environments.

Key Specifications

• Interface: Industry-standard I2C (Two-wire serial)
• I/O Count: 16 configurable bidirectional pins
• Hardware Addressing: 3 pins for up to 8 devices on the bus
• **Interru