They Manage Sensors, LEDs And Other Components Much Cheaper Than Implementations With Discrete Elements Only.

What started in PCs and carried over to devices like Smartphones is now common-place even for DIY projects: instead of trying to implement features exclusively with discrete elements like transistors and some ICs, it is much easier and more cost-effective to add a microcontroller.

Microcontrollers used in Computers and Smartphones

Here are some microcontrollers used in popular computers, notebooks, and smartphones:

Microcontroller Used In
Intel i3, i5, i7, i9, Xenon Computers running Windows (Microsoft)
AMD Ryzen 3, 5, 7, 9, EPYC Computers running Windows (Microsoft)
Apple Silicon M1, M1 Pro, M1 Max, M2 Computers running MacOs (Apple)
Apple A14, A15, … Bionic Apple iPhone Smartphones
Qualcom SnapDragon 4xxx, 6xxx, 7xxx, 8xxx Android Smartphones
Mediatec Helio, Dimensity Android Smartphones
Samsung Exynos Android Smartphones
Huawai Kirin Android Smartphones

These microcontrollers are fundamentally no different from the microcontrollers I am discussing in this section, however they are more powerful and harder to use: after all, they are designed to run full-fledged general-purpose operating systems.

In DIY projects and to control hardware, simpler microcontrollers are used that are much cheaper (cost is often below EUR 1.00/piece) and very much easier to program.

DIY Microcontrollers

In DIY projects and hardware projects, these are the typical microcontrollers used:

  • ATMega/Arduino: Arduino breakout boards started to make microcontrollers popular among hobbyist and makers because they are exceptionally easy to use and come with a proven toolset. Until recently, Arduinos exclusively used the ATMega family of microcontrollers. Meanwhile, some Arduino breakout boards also use ESP and other microcontrollers.
  • ESP/Espressif: Originally, the Chinese manufacturer Espressif produced cheap but powerful microcontrollers for the industry, and you find them in many smart devices. When Espressif released its ESP8266 in 2015, it soon was integrated into the Arduino tool chain and became an instant success, primarily because of its built-in WiFi and its very low price. Meanwhile, the family of (much more powerful but equally cheap) ESP32 has become the best DIY microcontrollers: they are much cheaper yet in almost all aspects more powerful than Arduino yet run the same code and can be programmed with the same tools.
  • ATtiny: for less computing intensive use cases, and when small size matters, ATTiny microcontrollers are are great alternative due to their very small size.
  • Raspbetty Pi: for more computing intensive use cases, Raspberry Pi microcontrollers can run a full-fledged operating system (and behave like a “real” computer), typically Raspberry Pi OS (based on Demian), Ubuntu, and others. Raspberry Pi is used for for projects that require a lot of computational power and a full operating system, and can act as a server in the backend. HomeAssistant is an example: it runs on a Raspberry Pi which acts as the HomeAssistant Server and lets you control IoT devices that in turn each base on one of the other mentioned microcontrollers. The latest evolution is Raspberry Pi 5

Development Boards

While you could use a naked microcontroller in your projects and wire it up manually, typically development boards are preferred: ready-to-go PCBs that combine a microcontroller with its most essential components such as a voltage regulator and a Serial-to-USB bridge.

Originals and Clones

While the microcontroller itself is always produced by a given manufacturer, the development boards are produced by a variety of sources. You can get original development boards from renown vendors such as Arduino, Adafruit, or Espressif, and you can get clones from lesser-known companies.

Clones are typically much cheaper than the originals, especially with Arduinos.

Clones discussed here have nothing to do with product piracy or trying to deceive. They clone functionality only, not appearance. You can always clearly identify whether a board was produced by a company like Arduino, or whether it is just functionality-wise the same but looks clearly different. Legal Clones Clones are possible because the hardware design is open-source, and it is neither rocket science nor a copyright infringement to add standard components like voltage regulators and UART chips to a PCB.

Clones are per se technically no better or worse than originals. They are different. Some vendors produce Clones with added benefit (like displays) at exceptional built quality. These can be more expensive than Originals. Other manufacturers use only the cheapest parts that barely meet the specifications. They still often work just fine yet cost only a fraction.

Here are the typical issues to be aware of (which coincidental are the very reasons for huge price differences):

Issue Symptom Remark
Cheap voltage regulator Once a few sensors/components are connected, the board starts to reboots or stops working was an issue with ESP8266, fixed for most other boards meanwhile
Soldering issues solder drops can cause short-circuits Related to the level of quality control. Occurs only with mass products under great pricing pressure. Even then rare (1 out of 100). Can often be fixed, if present will show from the start (no reliablity issue)
PCB Quality Labels hard to read Directly related to the price point, does not affect functionality

You decide what your focus is. Just keep in mind that one microcontroller won’t get you far. When comparing prices, compare the price differences for ten units.

Is Buying Clones Evil?

While technically ok, may it be a morally reprehensible to use Clones?`Are you possibly stealing intellectual property when you buy from obscure Asian profit makers? Are these taking advantage of other peoples’ development efforts to undercut prices?

No. Regardless of source, the microcontroller is always original and always legitimately purchased. The PCB circuit designs are open source. The tool chain is maintained by the community.

Cheap prices are more likely a result of lean production, less middlemen and less distributors. In fact, when you buy at a local store or at Amazon, you come across the very same boards that are also directly available at sources like AliExpress - just for a five- to tenfold price.


Please do leave comments below. I am using utteran.ce, an open-source and ad-free light-weight commenting system.

Here is how your comments are stored

Whenever you leave a comment, a new github issue is created on your behalf.

  • All comments become trackable issues in the Github Issues section, and I (and you) can follow up on them.

  • There is no third-party provider, no disrupting ads, and everything remains transparent inside github.

Github Users Yes, Spammers No

To keep spammers out and comments attributable, all you do is log in using your (free) github account and grant utteranc.es the permission to submit issues on your behalf.

If you don’t have a github account yet, go get yourself one - it’s free and simple.

If for any reason you do not feel comfortable with letting the commenting system submit issues for you, then visit Github Issues directly, i.e. by clicking the red button Submit Issue at the bottom of each page, and submit your issue manually. You control everything.


For chit-chat and quick questions, feel free to visit and participate in Discussions. They work much like classic forums or bulletin boards. Just keep in mind: your valued input isn’t equally well trackable there.

  Show on Github    Submit Issue

(content created Feb 15, 2024 - last updated May 22, 2024)