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The MCP23017 I2C 16-Bit I/O Expansion Module adds more digital input and output pins to a microcontroller. It is useful when an Arduino, ESP32, Raspberry Pi, or other control board does not have enough available GPIO pins.
The module connects through the I2C interface, which only needs two communication lines: SDA and SCL. It provides 16 extra GPIO pins divided into two groups of eight. Each pin can be set as an input or output through your program.
You can use the added pins to control LEDs, relays, buttons, switches, buzzers, displays, and other digital parts. The module also supports internal pull-up resistors, which are helpful when connecting push buttons and switches.
Three address pins allow up to eight MCP23017 devices to share one I2C bus. This means a project can have as many as 128 extra input and output pins while using the same SDA and SCL lines.
The MCP23017 also supports interrupt signals. It can alert the main controller when an input changes, reducing the need to check every pin repeatedly.
This expansion module is ideal for automation systems, robotics, control panels, LED projects, button boards, and school electronics activities. Its simple I2C connection helps reduce wiring while giving your project more control ports.
FAQ
Will this ship from Manila?
Yes — all stock ships from our Quezon City warehouse. Order before 4 PM weekdays for same-day cutoff via J&T or LBC.
Do you ship nationwide?
Yes. Metro Manila usually arrives next-day; provincial 1–3 working days.
Can I get this on a school PO or class order?
Yes — we accept Purchase Orders from accredited schools and universities. Contact us with your PO details and we'll process it.
Is this compatible with Arduino, ESP32, or Raspberry Pi?
Most parts work with common maker boards — check the description for specific pinout / voltage notes. If you're unsure, send us a message before ordering.
What's your return policy?
7-day inspection window for DOA units. Email proof of issue and we'll ship a replacement or refund. Used / installed parts are not returnable unless faulty.
Do you offer technical support?
Yes — questions land on our forum or via email, weekday or weekend. We've actually wired up most of what we sell.
Manila stock. Order before 16:00 PHT, ships today via J&T or LBC. Provincial: 1–3 working days.
Schools / class POs: we accept Purchase Orders for accredited schools and universities. contact us with your PO details.
Returns: 7-day inspection window for DOA units. Email proof of issue and we ship a replacement.
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