The Adafruit QT 5V to 3V Shifter Breakout lets you safely connect 3.3 V STEMMA QT / Qwiic sensors to 5 V microcontrollers like the Arduino Uno. Many I2C sensors and Qwiic-compatible devices are not 5 V safe — connecting them directly to a 5 V board risks damage. This breakout handles the voltage translation so your 3.3 V sensors stay protected.

On the input side, connect your 5 V microcontroller. The on-board 3.3 V regulator (500 mA) steps the power down while level-shifting circuitry translates I2C signals to 3.3 V on the output side. STEMMA QT / Qwiic connectors on both sides make wiring solderless, and breadboard breakout pins let you use it on a perfboard too.

Key Features

• 5 V to 3.3 V Regulation – On-board 3.3 V regulator provides up to 500 mA for connected sensors
• I2C Level Shifting – Safely translates 5 V I2C signals down to 3.3 V
• STEMMA QT / Qwiic Connectors – Plug-and-play I2C on both sides; no soldering required
• Breadboard Friendly – Breakout pins for prototyping; doubles as a QT-to-perfboard adapter
• Protects 3.3 V Sensors – Prevents over-voltage damage from 5 V microcontrollers

Also Consider

• QT 3V to 5V Level Booster – The reverse: boosts 3.3 V up to 5 V for sensors that need higher voltage

Ideal For

• Connecting 3.3 V Qwiic / STEMMA QT sensors to 5 V Arduino boards
• Protecting I2C devices that are not 5 V tolerant
• Bridging 5 V and 3.3 V I2C buses in mixed-voltage projects
• Breadboard prototyping with STEMMA QT breakout

Resources

• What is STEMMA QT?