MCP23017 I/O Expander
I2C GPIO expander for projects that need more input/output pins.
AI Ready Overview
Quick Summary
MCP23017 is a i/o expander commonly used in FYP and embedded projects. It is best for more gpio pins and button panels, with wiring and testing planned around Arduino, ESP32, Raspberry Pi.
Difficulty
Intermediate
Time Required
1-2 weeks for wiring, basic code, platform integration and repeated test readings
Cost
RM8-RM22 module range in Malaysia; full project cost depends on scope.
Components
MCP23017, Arduino, ESP32, Raspberry Pi
Overview
What is MCP23017?
MCP23017 adds 16 GPIO pins over I2C. It is useful for keypads, LEDs, buttons and status panels when the main microcontroller runs out of pins.
Engineering Reference
Quick Specs
| Operating Voltage | 1.8V-5.5V module-dependent |
|---|---|
| Interface | I2C, GPIO |
| Difficulty | Intermediate |
| Typical Malaysia Price | RM8-RM22 |
| Best For | More GPIO pins, Button panels |
Real Usage Notes
Suitable / Not Suitable
Suitable for
- ✓ More GPIO pins
- ✓ Button panels
- ✓ LED status boards
Not suitable for
- ✕ High-current outputs
- ✕ Very fast timing signals
- ✕ Motor drive without driver
Build Planning
Difficulty
MCP23017 is rated Intermediate. Plan around 1-2 weeks for wiring, basic code, platform integration and repeated test readingsdepending on wiring, libraries, calibration, dashboard/app integration and testing evidence.
Build Planning
Time Required
1-2 weeks for wiring, basic code, platform integration and repeated test readings
Malaysia Price Guidance
Cost
Typical module price range: RM8-RM22. This is component guidance only; a complete FYP cost depends on controller, sensors, casing, display, app/dashboard, documentation and timeline.
Connections
Pinout
VCC
Power input. Check whether the module expects 1.8V-5.5V module-dependent before wiring.
GND
Common ground with the controller and external supply.
I2C
Main I2C connection used by the module.
IO
Additional signal pins depend on the exact module variant.
Platform Notes
Wiring Guides
MCP23017 with Arduino / ESP32
Connect power, ground and the I2C / GPIO signal lines. Use level shifting when a 5V module connects to a 3.3V controller.
| MCP23017 VCC | 1.8V-5.5V module-dependent |
|---|---|
| MCP23017 GND | Controller GND |
| Signal pins | I2C, GPIO |
Fix Common Problems
Troubleshooting
Troubleshooting
Common Mistakes
FYP Ideas Using MCP23017
Related Projects
Compare Options
Alternative Components
Student Questions
FAQ
Is MCP23017 good for FYP projects?
Yes, MCP23017 is suitable for FYP work when the project matches its limits: More GPIO pins and Button panels.
What is the most common MCP23017 mistake?
Driving loads directly