MCP23S17T-E/SS

The MCP23017/MCP23S17 (MCP23X17) device family provides 16-bit general-purpose parallel I/O expansion for I2C bus or SPI applications. The two devices differ only in the serial interface. The MCP23X17 consists of multiple 8-bit configuration registers for input, output, and polarity selection. The system master can enable the I/Os as inputs or outputs by writing to the I/O configuration bits (IODIRA/B). The data for each input or output is stored in the corresponding input or output register. The polarity of the input port registers can be inverted using the polarity inversion register. All registers can be read by the master system. The 16-bit I/O port functionality consists of two 8-bit ports (PORTA and PORTB). The MCP23X17 can be configured to operate in 8-bit or 16-bit mode via IOCON.BANK. There are two interrupt pins, INTA and INTB, which can be associated with their respective ports or logically OR'ed together so that both pins will be activated when either port causes an interrupt. The interrupt output can be configured to activate under two conditions (mutually exclusive): 1. When any input state differs from its corresponding input port register state. This is used to indicate to the system master that the input state has changed. 2. When the input state differs from the preconfigured register value (DEFVAL register). The interrupt capture register captures the port value at the time the interrupt occurs, thereby preserving the condition that caused the interrupt. Power-on Reset (POR) sets the registers to their default values and initializes the device state machine. The hardware address pins are used to determine the device address.

Key features

• 16-bit remote bidirectional I/O port — I/O pins default to inputs
• High-speed I2C interface (MCP23017) — 100 kHz, 400 kHz, 1.7 MHz
• High-speed SPI interface (MCP23S17) — 10 MHz (max)
• Three hardware address pins supporting up to 8 devices on the bus
• Configurable interrupt output pins — configurable as active-high (output), active-low (output), or open-drain (output)
• INTA and INTB configurable for independent or combined operation
• Configurable interrupt sources — interrupt-on-change based on configured register default values or pin level changes
• "Polarity inversion" register for configuring input port data polarity
• External reset input
• Low standby current: 1μA (maximum)
• Operating voltage:
• 1.8V to 5.5V (-40°C to +85°C)
• 2.7V to 5.5V (-40°C to +85°C)
• 4.5V to 5.5V (-40°C to +125°C)