How Small Can the ESP32 Get?

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How Small Can the ESP32 Get?

The author challenges to create an ESP32 microcontroller as small as possible.

While reducing the size, he had to give up some features of the ESP32, such as only one GPIO pin being available, no battery charging functionality, and even lacking a Wi-Fi antenna.

After completion, it was found that the RGB LED was installed on the back, causing its pads to be misaligned. However, fortunately, the basic functions can still be realized.

The author also mentioned that if using 0201 level components (he used 0401 level components in the project) and finding smaller buttons, the ESP32 could be made even smaller.

Source:https://hackaday.com/2023/09/07/how-small-can-the-esp32-get/

PCB Watch Based on Pomodoro Technique

This watch operates based on the Pomodoro time management technique, which divides your work time into segments, each lasting 25 minutes, followed by a short break.

The watch uses an ATTiny85 microcontroller, which manages the time and controls the vibration motor and RGB LED lights. When the work time reaches 25 minutes, the microcontroller drives the vibration motor and changes the light, notifying the user it’s time to rest. Conversely, after the rest period ends, the microcontroller again drives the vibration motor and lights, prompting the user to start the next work session.

Additionally, if you want to know how much time is left, you can press the button on the watch, and the RGB LED will display different colors based on the remaining time, which is also controlled by the ATTiny85.

The watch is powered by a 3.7-volt battery, and the PCB is responsible for connecting and laying out all components.

To reduce power consumption, some optimizations were made in the code, including setting sleep mode, turning off unnecessary analog-to-digital converters, and setting all unused pins to INPUT_PULLUP mode.

The accuracy of the time displayed on the screen is not very high because the project chose to use the internal watchdog timer of the microcontroller for timing. This timer, while convenient, is not particularly accurate. Therefore, when timing for 25 minutes, there may be about a 2-minute error.

Source:https://www.hackster.io/vinvout1/diy-pomodoro-pcb-watch-boost-your-productivity-516ed2

Pikachu Charger

This project is a wearable PCB shaped like Pikachu, featuring glowing cheeks and the ability to charge lithium polymer (LiPo) batteries.

The main components of the project include a custom PCB from JLCPCB, some electronic components with resistance of 1k and capacitance of 4.7uF, reverse-mounted red and green LEDs, a battery connector, as well as an MCP73831T-2ACI/OT charging IC and a Micro-USB socket.

The operation of the project is as follows:

1. The charging IC (MCP73831T-2ACI/OT) receives power input via Micro-USB and then charges the LiPo battery connected to the battery connector.

2. The red and green LEDs in the project are reverse-mounted and can emit light through the PCB’s FR-4 material when charging, enhancing visibility and appeal.

3. The project is compact and portable, small enough for users to wear and use when a mobile power solution is needed.

During the design process, the software used for the project was Altium Designer, a powerful EDA (Electronic Design Automation) tool for electronic product design, circuit design, and PCB layout.

Through this practical project, the creator achieved a childhood dream, not only lighting up Pikachu’s cheeks but also helping to charge different electronic devices or LiPo batteries in projects.

Source:https://www.hackster.io/ayesha-iftiqhar/pikachu-charger-912a48

Automatic Feeder

A simple solution for pet feeding using a servo and a plastic bottle.

Source:https://www.instagram.com/p/CdbdDpXoiG3/

Raspberry Pi Powered Stylish Wired Headphones

Instagram blogger — Moonshake3d designed and created wired stereo headphones driven by two synchronized Raspberry Pis, providing the ultimate high-fidelity stereo experience.

After completing the white version, he even designed and manufactured a fully transparent plastic version! It’s simply a work of art!

Source:https://www.instagram.com/moonshake3d/

This weekly report was first published in the DF Maker Community. Copyright Agreement: WTFPL