How TINY Can I go? The BEST Power Board is here!

Summary

The video covers customizing and minimizing the size of a 3.3/5V DC voltage regulator circuit board from AliExpress while maintaining performance. It starts by analyzing the original commercial board's design and components. Then, smaller versions are iteratively created using smaller 0805 components and tiny power inductors from Würth Elektronik. Despite significantly reducing the boards' size, the new versions perform well in terms of efficiency, noise, and output current. Their EMC compatibility will be evaluated in a future video. Overall, it shows that with careful design, substantial miniaturization of this regulator board is possible while retaining adequate functionality.

Takeaways

• 😀 The video features a useful but large DC-DC converter circuit board from AliExpress and tries to create more compact custom versions
• 👨‍🔬 The key component is the TPS6302 IC which needs proper selection of inductors, capacitors and resistors to work well
• 🔬 Several iterations of new board designs are created, testing different component sizes and placements for maximum miniaturization
• 👍 The custom boards perform very well, with only minor performance tradeoffs compared to larger versions
• 🔋 Efficiency, output current capability and noise levels are characterized across different designs and load conditions
• 😮 The smallest 1cm x 1cm design works surprisingly well, although efficiency decreases and noise increases slightly
• 📏 Component sizes play a major role in board miniaturization, with tiny 0805 passives and compact power inductors being key
• 💡 Good PCB layout following datasheet guidelines is also critical for achieving excellent performance
• ⏩ Further testing is needed to ensure the boards meet EMC requirements before production and sales
• 👋 The project demonstrates the potential for significant size reductions of useful circuit boards through careful optimization

Q & A

What makes the circuit board featured in the video a 'hidden gem'?

The circuit board is a hidden gem because it can provide stable 3.3V or 5V output while only requiring around 25uA of current to keep the output voltage stable. This makes it great for super low power projects.

Why is the AliExpress circuit board so large?

The AliExpress circuit board is large because it utilizes more components than necessary, including extra capacitors and resistors. It also breaks out the power save and enable pins which takes up space.

How did the author reduce the size of the circuit board?

The author reduced the size by only using the minimum necessary components, switching to smaller 0805 sized capacitors and resistors, and utilizing tiny 1.5uH inductors from Würth Elektronik.

How did the author's smaller boards compare in performance?

The author's smaller boards had slightly decreased max current, efficiency, and increased noise compared to the original AliExpress board, but overall still performed very well.

What is the purpose of the vias on the circuit board?

The vias connect the top and bottom copper layers, allowing the use of a solid bottom GND plane to reduce resistance.

What measurements were done to evaluate board performance?

Measurements included max output current, efficiency across different loads, and noise levels to quantify performance.

What was the smallest board size achieved?

The smallest board achieved was around 30% smaller than the original AliExpress board.

What IC is at the heart of the converter circuit?

The key IC in the converter circuit is the TPS6302.

What is the purpose of the feedback pin on the IC?

The feedback pin allows selection of the output voltage through a resistor voltage divider.

What future test is planned for the boards?

The author plans to test if the boards exceed any electromagnetic compatibility (EMC) limits.