SCD41 — i2c address & wiring
True photoacoustic CO2 — the SCD40's higher-range, single-shot-capable sibling.
Key facts
SCD41 at a glance
| i2c address | 0x62 fixed address |
|---|---|
| Logic voltage | 3.3–5 V |
| Type | sensor |
| Part | Sensirion SCD41 |
| Ships with | Qwiic, STEMMA QT |
| Datasheet | Sensirion SCD41 — manufacturer documentation ↗ |
The chip
What the Sensirion SCD41 actually is
High-accuracy photoacoustic NDIR carbon dioxide (CO₂) sensor measuring CO₂ concentration, temperature and relative humidity. Offers a single-shot low-power mode and improved accuracy compared to the SCD40 while keeping automatic self-calibration and long-term stability.
Wiring
How to connect the SCD41
The SCD41 talks i2c at address 0x62. It runs at 3.3–5 V, so match your host's logic level — if your host is 5 V and a board on the bus is 3.3 V-only, add a level shifter. Use the compatibility checker to confirm the exact cable for your setup.
The address is fixed, so two SCD41s can't share a bus directly — the address-conflict guide covers the workarounds (multiplexer, second bus).
Wiring is the usual four: power, ground, SDA and SCL, plus pull-up resistors — almost always already fitted on the breakout. Nothing showing up? Run an i2c scan first; if the bus is silent, the 7-step checklist finds it faster than guessing.
Ecosystems
Plug-together options for the SCD41
SCD41 breakouts ship with Qwiic and STEMMA QT — keyed 4-pin cables carrying power, ground, SDA and SCL, so there's nothing to solder and nothing to wire backwards. Chain it to the next board and keep going.
Running a mixed bench? Those ecosystems interoperate more than their marketing suggests — see every connector pairing for the cable or adapter you need, or the standards overview for how they compare.
Go deeper
Guides covering the SCD41
Alternatives
Other air quality boards
Get one
Questions
SCD41 i2c FAQ
What is the SCD41's i2c address?
The SCD41 sits at a fixed address of 0x62. It can't be changed, so two of them can't share one bus without a multiplexer or a second bus.
What voltage does the SCD41 run at?
3.3–5 V logic. That range covers both 3.3 V and 5 V hosts, so it drops onto a Pi, ESP32 or Arduino without a level shifter.
Can I use two SCD41s on one i2c bus?
Not directly — every SCD41 answers to 0x62, so two on one bus would collide. Use a TCA9548A multiplexer to give each its own channel, or put the second one on a separate bus.
Does the SCD41 work with Qwiic and STEMMA QT?
Yes — SCD41 breakouts ship with Qwiic / STEMMA QT, so it plugs straight in with no soldering. Mixing ecosystems? The compatibility checker gives you the exact cable or adapter.