A weather station is one of the most popular projects among makers.
Blinking an LED is fun at first, but it gets boring quickly.
When you build your own weather station, it will serve you for a long time — the longer it runs, the better, as you’ll collect long-term statistics.
And with your own station, you might even detect a volcanic eruption on the other side of the world (thanks to a pressure sensor recording the shockwave).
We know not everyone can or wants to design their own hardware, so we’re introducing our development board designed specifically (but not only) for weather stations — LaskaKit Meteo Mini.
This development board based on ESP32-C3 (a major upgrade from the older, less efficient ESP12S/ESP8266 version) makes building your weather station easier.
It includes everything you need to get started — and can be easily expanded with additional sensor modules.
| Parameter | Value |
|---|---|
| Board version | v4.1 |
| Microcontroller | ESP32-C3-MINI (Wi-Fi, BLE, RISC-V core) |
| USB input voltage | 3.4–5.5 V |
| Solar input voltage | 5–10 V (recommended 6 V solar panel) |
| Deep-sleep current consumption | 23 μA |
| Antenna connector (IPEX version) | IPEX3 |
| Power supply | USB-C or single-cell Li-Ion battery |
| Charging IC | BQ24074RGTR with charging indicators (LED CHG/POWER GOOD).NTC allows battery charging only within the safe temperature range of 0 °C to 50 °C. |
| USB interface | CH9102F |
| Voltage regulators | RT9080 (ESP), RT9080 (peripherals, IO4 → HIGH to enable) |
| Dimensions | 48.4 × 32.9 × 9 mm |
| Weight | 8 g |
On the front of the board, you’ll find the Wi-Fi module with ESP32-C3.
It delivers higher performance than the older ESP8266 version and is much more energy-efficient — consuming only 23 μA in deep-sleep mode.
The module supports IEEE 802.11 b/g/n Wi-Fi standards.
The CH_CURRENT solder bridge allows you to set the maximum charging current for the battery: 1.0 A or 1.34 A, depending on resistor configuration (see schematic).
The board can be powered off using the onboard power switch.
On the right side, there’s a USB-C connector for charging and power input.
At the bottom, you’ll find connectors for a Li-Ion battery (Battery) and a solar panel (Solar).
On the right side, there’s also a 1-Wire interface for the DS18B20 temperature sensor (GPIO10).
On the left side, you’ll find a set of µSup connectors – our custom connector standard compatible with SparkFun Qwiic and Adafruit STEMMA.
In addition to the standard I2C µSup connector, there are also µSup SPI and µSup IO connectors.
Power for the µSup connectors is controlled via GPIO4 (HIGH = enabled), allowing for even lower power consumption.
A 3.3 V voltage regulator is integrated directly on the board.
Battery voltage is measured using a voltage divider (1 MΩ and 1.3 MΩ) connected to IO0 (ADC input).
| Interface | Connector | Signals |
|---|---|---|
| µSup I2C | JST-SH 4-pin | SDA: IO19, SCL: IO18 |
| µSup SPI | JST-SH 6-pin | CS: IO3, MOSI: IO7, SCK: IO6, MISO: IO2 |
| µSup IO | 2× JST-SH 3-pin | IO1, IO10 (supports DS18B20) |
Power from USB-C and the solar panel is combined through protection diodes into the input of the BQ24074 charging IC.
Connecting both power sources simultaneously is safe.
The recommended solar panel is 6 V, but 10 V panels can also be safely used.
Charging current is configurable using the CH_CURRENT solder jumpers: 0.5 A (default), 1.0 A, or 1.34 A (when all three jumpers are bridged).
Charging status is indicated by LEDs — CHG (charging) and POWER GOOD (fully charged).
The battery voltage (VCC) is connected through a resistor divider to the IO0 (ADC) input of the ESP32-C3 microcontroller.
- Addressable RGB LED: SK6812-EC20 on IO9
- Button: IO5 → pressed = LOW
- Temperature sensor: NTC 10 kΩ (3435) – for battery temperature monitoring
Install ESP32-C3 support in Arduino IDE.
For versions 3.5 and newer (including v4.1), no external programmer is required — the CH9102F interface is already integrated on the board.
Older versions can use the CH340C programmer.
Example code and libraries are available here:
👉 https://github.com/LaskaKit/Meteo_Mini/tree/main/SW/
The board is available in two variants:
- with an integrated PCB antenna
- or with an external antenna connector (IPEX3)
👉 https://www.laskakit.cz/laskakit-meteo-mini/
A 3D-printable case model is available:
And yes — we actually use what we sell (photo of an earlier version):
- IO3 was used to enable peripherals (µSup connector power).
- Maximum solar panel input voltage: 6 V.
- Charging IC: TP4054 – lower efficiency, no direct solar input support.
- No µSup SPI or µSup IO connector.
