The MCP23009-E/MG is an 8-bit I/O Expander with I2C? compatible interface operating at speeds of up to 3.4MHz. The MCP23X09 device provides 8-bit, general purpose parallel I/O expansion for I2C bus or SPI applications. The MCP23X09 consists of multiple 8-bit configuration registers for input, output and polarity selection. The system master can enable the I/Os as either inputs or outputs by writing the I/O configuration bits. The data for each input or output is kept in the corresponding input or output register. The polarity of the input port register can be inverted with the polarity inversion register. All registers can be read by the system master.
Low standby current as low as 1 μA
High-speed I2C? interface
Single hardware address pin, voltage input to allow up to eight devices on the bus
Configurable interrupt output pins - Configurable as active-high, active-low or open-drain
Configurable interrupt source - Interrupt-on-change from configured defaults or pin change
Polarity inversion register to configure the polarity of the input port data