0 - Introduction
If you have great plans for your next hobby project, you might be struggling to find the best cheap microcontroller. If that is the case, then you are in the right article. In here we will compare 5 microcontrollers from AliExpress, all under 5€ at the time of writing, by checking the specifications and developer experience with each one.
1 - Arduino Nano Clone (ATMega)
This Arduino Nano Clone has an original ATMEGA328P-AU processor and should be compatible with any Arduino Nano breakout board and program. It also comes with a type-c port as input and should be perfect for simple projects such as robotics, instrumentation and automation.
In the following table you can check the specifications of the board as well as the name it has in AliExpress:
| Specs | 'Type-C Welding' |
|---|---|
| Chip | ATMEGA328P-AU |
| Clock | 16 MHz |
| Memory | 32KB Flash + 2KB SRAM + 1KB EEPROM |
| Interfaces | USB, SPI, I2C, UART |
| Voltages | 7-12V input, 5V operating |
Should you buy it? The arduino ecosystem is pretty big, so support won’t be an issue. It is also very cheap, so i can recommend, if it satisfies your needs.
2 - SMT8
This SMT8 Devboard also has a type-c port as input and can accept a wider range of input voltages and is cheaper than the Arduino. On the other hand, it does have much less memory to store and execute your code while also being harder to code with.
| Specs | 'STM8S103F3P6 TYEPC-C' |
|---|---|
| Chip | STM8S103F3P6 |
| Clock | 16 MHz |
| Memory | 8KB Flash + 1KB RAM + 640B EEPROM |
| Interfaces | USB, SPI, I2C, UART |
| Voltages | 4.5-15V input, 2.95 - 5.5V operating |
For the reasons given above, I recommend the Arduino Nano Clone instead of the SMT8, unless you need a large quantity of boards, or you need a specific SMT function, For a hobbyist, it just makes more sense to go with the arduino.
3 - SMT32
| Specs | 'STM32F103C8T6 Weld' |
|---|---|
| Chip | STM32F103C8T6 |
| Clock | 72 MHz |
| Memory | 64KB Flash + 20KB RAM |
| Interfaces | USB, SPI, I2C, UART, CAN |
| Voltages | 3.3-5.0V input, 2.0-3.6V operating |
Again, i would only buy this STM board if cost is an issue with the others, because even though it is powerfull, you need STM LINK, the usb device sold in the same page and a program, which add a little to the cost. and the others are also much easier to use.
4 - RP2040
The Raspberry Pi Pico has a RP2040 chip, made by the same company that made the mini computer Raspberry Pi, it’s support is very good with a lot of community documents and projects, mainly in cpp, c and python. It is also a lot faster and has way more memory than the previous boards, but it lacks CAN support.
| Specs | 'Weld RP2040 TYPE-C' |
|---|---|
| Chip | RP2040 |
| Clock | 133 MHz, Dual-Core |
| Memory | 2MB Flash + 264KB RAM |
| Interfaces | USB, SPI, I2C, UART |
| Voltages | 1.8-5.5V input, 3.3V operating |
The Pico is a very good choice for anything that you could need besides wireless communication and CAN, but you can easely solve that with an external module, sadly that can become a bit expensive compared to just buying another controller. Another problem i have with the Pico is the lack of supply, sometimes it goes out of stock and stays that way for a while, rising prices.
5 - Esp32
The Esp32 is, for me, the holy grail of microcontrollers. It has WiFi, Bluetooth, CAN, touch sensors, two ADCs, a powerfull cpu, good memory and can be programmed via USB with the Arduino IDE, or platformIO, so you have a powefull package that is easy to use. The only downside is it’s price, as it is the one that get’s closer to the 5€ mark.
| Specs | 'Weld RP2040 TYPE-C' |
|---|---|
| Chip | Esp32 |
| Clock | 240 MHz, Dual-Core |
| Memory | 4MB Flash + 512KB RAM |
| Interfaces | SPI / I2C / I2S / SDIO / UART / TWAI (CAN) / WiFi / Bluetooth / IR |
| Voltages | 3.6-18V input, 3.0-3.6V operating |
In general i would always choose the Esp32. If power is a problem you can put it to sleep and disable most of it’s functions until they are needed and if you need any kind of wireless communications it is the logical choice.
What do you think? Do you know any other cheap microcontroller that you want us to review? If you do, contact us and give us your opinion.
As always, thanks for reading and stay tuned for more tech insights and tutorials. Until next time, and keep exploring the world of tech!