MCP23S08T-E/SS

I/o Expanders Overview

The MCP23S08T-E/SS is an 8-bit I/O expander with SPI interface in a 20-pin SSOP package. It operates at 1.8V to 5.5V, supporting up to 10 MHz clock frequency across -40°C to +125°C. Features include configurable interrupt output, hardware address pins (A1/A0), and internal pull-ups. The device provides bidirectional GPIO expansion via serial control registers for direction, polarity, and interrupt configuration.

I/o Expanders Feature Summary

• Provides 8-bit general-purpose parallel I/O expansion through a high-speed SPI serial interface.
• Includes a configurable interrupt output pin that supports active-high, active-low, or open-drain configurations.
• Features hardware address selection using two pins to allow multiple devices on the same bus.
• Integrates internal weak pull-up resistors on all I/O pins and supports input polarity inversion.

I/o Expanders Applications

• Embedded systems requiring additional GPIO ports via SPI communication.
• Industrial control interfaces needing remote I/O expansion over long distances.
• Consumer electronics utilizing low-power microcontrollers with limited native pins.

I/o Expanders Procurement Notes

Verify the ordering suffix matches the required package type and temperature grade. Confirm the specific revision of the datasheet aligns with your design requirements. Ensure compatibility with your system's SPI voltage levels and timing constraints before finalizing procurement decisions.

I/o Expanders Selection Notes

Select this component when SPI connectivity is preferred over I2C due to higher speed requirements or simpler protocol implementation. Consider the 20-pin SSOP package for space-constrained PCB layouts. Evaluate the need for hardware address pins if multiple expanders are used on a single SPI bus segment.

I/o Expanders Part Context

This part belongs to the MCP23X08 family of 8-bit I/O expanders. It differs from the MCP23008 by using an SPI interface instead of I2C and having only two hardware address pins rather than three. It shares similar register maps and functional capabilities with other members of the series.

I/o Expanders Replacement Considerations

Direct substitutes include the MCP23S08 without the 'T' suffix if tape-and-reel packaging is not required. For I2C applications, the MCP23008 is functionally similar but requires different addressing logic. Verify pinout compatibility when replacing with other 8-bit SPI expanders.

I/o Expanders FAQ

How many hardware address pins does the MCP23S08 have?

The MCP23S08 has two hardware address pins (A1 and A0), allowing up to four devices to be addressed on the same SPI bus using the same Chip Select line.

What is the maximum operating voltage for the MCP23S08?

The maximum operating voltage for the MCP23S08 is 5.5V across its entire specified temperature range.

Can the interrupt output be configured as open-drain?

Yes, the interrupt output pin can be configured as open-drain by setting the ODR bit in the IOCON register.