D1 mini 4.0 - 5V CO2 Sensor

Hi there,

i’ve got a D1 Mini V4.0.0 and it unfortunately doesn’t have a 5v connector. I would like to use a MHZ19, because I have heard a lot of good things about it.

So what can I do to still use it? Would it be an option to get the 5v of the usb cable?

Does anyone have experience with the ccs811?

I’m very new to this, so any help is very appreciated. If there are better CO2 Sensors, that I should use, please let me know.

Is the vbus pin 5v?

look here

@TimoVie hello CCS811 is 3.3v. Yes 5v is coming in on the UBS if you need it. All these devices need current so you just need to make sure you don’t create power dips. Every board I have, needs a different power requirements; some have voltage bucks to allow me to supply 24v/12v/5v/3.3v. Happy DIY

I use SCD40 and BME680. The container, location and each item are all make measurements very variable. I suggest you do a search on this forum; there are many many long dialogues on these items.

@Arh I have same boards; but I can not remember for the life of me whether vbus is 5v and the small print on that page says ALL pins are 3.3v. Need a multimeter!

Are you happy with the SCD40? Would be perfect since it supports 2,4-5,5 V. How difficult is it for a beginner to set it up?

@TimoVie hours and hours of fun fiddling. Welcome to DIY. there is lots of reading time on this forum. yaml is below for this sensor (and also on the ESPHome web site where I originally copied it from).

  - platform: scd4x
      name: "Kitchen Ceiling CO2"
      name: "Kitchen Ceiling Temperature"
      accuracy_decimals: 1
        - median:
      name: "Kitchen Ceiling Humidity"
      accuracy_decimals: 0
        - median:
    temperature_offset: 3
    ambient_pressure_compensation_source: bme680pressure
    update_interval: 30s

Thanks! Is it just connecting power and I2C Connectors? Or does it need much calibration?