MCP23S09 is an 8-bit I/O expander with SPI interface operating at 10 MHz. The MCP23S09 is available in 18-pin PDIP (300 mil), 18-pin SOIC (300 mil) and 16-pin 3x3mm QFN package

• 8-bit remote bidirectional I/O port:
  • I/O pins default to input
• Open-drain outputs:
  • 5.5V tolerant
  • 25 mA sink
  • 200 mA total
• Low standby current as low as 1 µA
• High-speed SPI interface at 10 MHz
• 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
• External reset input