Comparison page

MCP23017 vs ULN2003

Side-by-side selection notes for specs, ecosystem readiness, known issues, and data confidence. This page is generated from structured component fields instead of a hand-written article.

MCP23017

Projects needing IO expansion and 16 pins with a commonly available power part.

ULN2003

Projects needing Driver array and Stepper kit with a commonly available power part.

Specification Matrix

DimensionMCP23017 ULN2003

CategoryPowerPower

MakerMicrochipTexas Instruments

CoreNot specifiedNot specified

ClockNot specifiedNot specified

WirelessNot specifiedNot specified

Voltage3.3V3.3V

LibrariesArduino, MicroPythonArduino

Price$1.00 - $3.50$0.10 - $0.60

Known Tradeoffs

MCP23017

Breakout boards may use different pin labels or regulator choices
Clone modules can differ from the original datasheet part

ULN2003

Breakout boards may use different pin labels or regulator choices
Clone modules can differ from the original datasheet part

Open Individual Model Pages

MCP23017

Microchip

16-bit I2C GPIO expander used when a microcontroller needs many extra digital pins.

China-madePower86% confidence

ULN2003

Texas Instruments

Darlington transistor array often sold with 28BYJ-48 stepper motor kits.

China-madePower82% confidence