In this article we look at an expansion board which I purchased, the board is called the Pico Sense Hat and is made by SBcomponents
It has a 1.14″ LCD Display which is controlled by a ST7789, the addition of this LCD allows you to display readings from the sensors on it.
If you connect this to a raspberry pi pico w then you have the potential to create an IoT device in a small size
The expansion board has the following 4 sensors which cover all your environmental needs
sgp40
The SGP40 is Sensirion’s digital VOC (volatile organic compounds) sensor designed for easy integration into air purifiers or demand-controlled ventilation.
SGP40 is Sensirion’s new digital VOC (volatile organic compounds) sensor designed for easy integration into air treatment devices and air quality monitors. Based on Sensirion’s CMOSens® Technology, the SGP40 offers a complete sensor system on a single chip and features a digital I²C interface, a temperature-controlled micro-hotplate and a humidity-compensated indoor air quality signal.
In combination with Sensirion’s VOC Algorithm (part of the gas index algorithm software), the sensor signal can be directly used to evaluate indoor air quality, e.g., for triggering the gradual fan control of an air treatment device.
sht31
The digital SHT3x humidity sensor is the successor of the SHT2x series. The SHT3x humidity sensor series consists of a low-cost version with the SHT30 humidity sensor, a standard version with the SHT31 humidity sensor, and a high-end version with the SHT35 humidity sensor.
Automotive grade versions are also available. The SHT3x humidity sensor series combines multiple functions and various interfaces (I²C, analog voltage output) with a applications-friendly, very wide operating voltage range (2.15 to 5.5 V).
bme280
The BME280 is a humidity sensor especially developed for mobile applications and wearables where size and low power consumption are key design parameters.
The unit combines high linearity and high accuracy sensors and is perfectly feasible for low current consumption, long-term stability and high EMC robustness.
The humidity sensor offers an extremely fast response time and therefore supports performance requirements for emerging applications such as context awareness, and high accuracy over a wide temperature range
tcs34725
The TCS3472 device provides a digital return of red, green, blue (RGB), and clear light sensing values. An IR blocking filter, integrated on-chip and localized to the color sensing photodiodes, minimizes the IR spectral component of the incoming light and allows color measurements to be made accurately.
The high sensitivity, wide dynamic range, and IR blocking filter make the TCS3472 an ideal color sensor solution for use under varying lighting conditions and through attenuating materials.
This data is transferred via an I2C to the host.
These 4 sensors and the display controller can be programmed with micropython, circuitpython and even the Arduino IDE
Resources
he following resources are available
- STEP File
- Product Dimension
- 3D PDF File
- Schematic File
- GitHub
- WiKi
- Enclosure Top STL File
- Enclosure Bottom STL File
