SparkFun SGP40 SHTC3 STC31 MicroMod Environmental Function Board

The SEN-18632 board incorporates three sensors to monitor air quality SGP40, humidity & temperature SHTC3, and CO2 concentrations STC31 in your indoor environment. With M.2 MicroMod connector no soldering is required to connect to the main board.

• Input voltage range

  • 2.5V to 6.0V
    • Typ. 5V via Main Board's USB connector
    • Typ. ~3.7V to 4.2V via Main Board's LiPo battery Connector
• I/O voltage

  • 3.3V
• AP2112 3.3V voltage regulator (rated 600mA)
• Power LED
• I2C pull-up resistors
• Sensirion SGP40 Air Quality Sensor

  • Uses I2C interface
    • Address: 0x59 (default)
  • Operating voltage range
    • 1.7V to 3.6V (Typ. 3.3V)
  • Operating temperature range
    • -20C to +55C
  • Typical current consumption
    • 2.6mA during continuous operation (at 3.3V)
    • 34uA when idle (heater off)
  • Output signal
    • Digital raw value (SRAW): 0 - 65535 ticks
    • Digital processed value (VOC Index): 0 - 500 VOC index points
  • Switch-on behavior
    • Time until reliably detecting VOC events: <60s
    • Time until specifications are met: <1h
  • Recommended sampling interval
    • VOC Index: 1s
    • SRAW: 0.5s - 10s (Typ. 1s)
• Sensirion SHTC3 Humidity and Temperature Sensor

  • Uses I2C interface
    • Address: 0x70 (default, non-configurable)
  • Operating voltage range
    • 1.62V - 3.6V (Typ. 3.3V)
  • Operating temperature range
    • -40C to +125 C
  • Relative Humidity
    • Measurement range: 0% to 100%
    • Typical accuracy: +-2 %RH
    • Resolution: 0.01 %RH
  • Temperature
    • Measurement range: -40C to +125 C
    • Typical accuracy: +-0.2 C
    • Resolution: 0.01 C
  • Typical current consumption (varies based on mode)
    • 4.9uA to 430uA (Normal Mode)
    • 0.5uA to 270uA (Low Power Mode)
  • Allows the STC31 to compensate for humidity and temperature
• Sensirion STC31 CO2 Sensor

  • Uses I2C interface
    • Addresses: 0x29 (default), 0x2A, 0x2B, 0x2C
  • Operating voltage range
    • 2.7V to 5.5V (Typ. 3.3V)
  • Operating temperature range
    • -20 C to +85 C
  • Calibrated for CO2 in N2 and CO2 in air
  • Measurement ranges
    • 0 to 25 vol% in N2
    • 0 to 100 vol% in air
  • Accuracy
    • 0.5 vol% + 3% measured value in N2
    • 1 vol% + 3% measured value in air
  • Concentration and temperature resolution: 16-bit
  • Repeatability: 0.2 vol%
  • Temperature stability: 0.025 vol% / C
  • Start-up time: 14 ms
  • Thermal conductivity sensor provides calibrated gas concentration and temperature output
• Jumpers
  • PWR LED
  • I2C pull-up resistors
  • STC31 address selection

• Schematic
• Eagle Files
• Board Dimensions
• Hookup Guide
• SGP40

  • SGP40 Datasheet
  • VOC Index for Experts
  • SGP40 Design In Guide
  • SGP40 Quick Testing Guide
• SHTC3

  • SHTC3 Datasheet
• STC3X

  • STC31 Datasheet
  • STC Field Calibration Guide
  • STC Design-In Guide
• Arduino Libraries

  • SGP40
  • SHTC3
  • STC3X
• GitHub Hardware Repo