Проектируем цифровой DC-DC с контролем тока и напряжения!

Summary

In this episode on the 'Arduino Notes' channel, we delve into the development of a digital DC-DC converter project that started over a year ago. Using a DAC and a comparator, the host explores the construction of a prototype that can regulate voltage and current, aiming for compactness, precision, and low ripple. The video covers the ordering of dual and four-layer PCBs, leveraging a debit card offer to offset costs, and dives into the technical intricacies of creating a power supply module capable of delivering up to 24V and 4A. The prototype's design, calibration methods, and performance tests, including response to load changes and ripple suppression, are discussed. Future improvements and a shift towards using an STM32 microcontroller for enhanced control and efficiency are also highlighted.

Takeaways

• 🚀 The video continues exploring Arduino projects, specifically focusing on digital DC-DC converter prototypes.
• 📲 Viewers are encouraged to contribute to the project's development by sharing thoughts and remarks in the comments.
• 💳 The presenter mentions a debit card offer that provides cashback on purchases, highlighting personal long-term use.
• 🛠 The video showcases the construction of a power supply module with voltage and current control up to 24V and 4A, emphasizing compactness, accuracy, and low ripple.
• 🕖 A more complex but suitable topology was used for the module, improving upon simpler designs with precise voltage control via additional resistors and DACs.
• 💻 Prototyping involved ordering two sets of PCBs with dual-layer and four-layer stacks, emphasizing the importance of grounding and signal isolation.
• 🔬 The presenter describes the assembly process, preferring manual soldering over solder paste, and introduces a budget-friendly reflow oven used for the project.
• 📱 Control of the module is demonstrated using an Arduino Nano, with commands sent through a serial port for testing voltage and current settings.
• 💬 Different calibration approaches are discussed for achieving precise output voltage, including a macro for direct DAC value calculation and a simplified mapping method.
• 🚧 The video also covers current limiting functionality, utilizing a shunt, comparator, and another DAC for protection and charging applications.
• 🔧 Future improvements include replacing some components with a single STM32 microcontroller for enhanced performance and cost-effectiveness.

Q & A

What is the main topic of the video presented by the Arduino enthusiast channel?

The main topic is the continuation of exploring digital DC-DC converters, focusing on a prototype that allows for voltage and current control using a more complex but suitable topology.

What are the benefits of using a debit card mentioned in the video?

The benefits include cashback on every purchase, promotional offers with up to 15% and 30% discounts, free transfers to other banks, and a highly-rated banking app.

Why is digital control over DC-DC converters important?

Digital control offers flexibility for automation, testing, and creating power sources or charging devices with one or multiple channels, providing a more adaptable solution than traditional modules with manual adjustments.

What was the initial goal in creating the module discussed in the video?

The initial goal was to create a module capable of delivering up to 24V and at least 4A peak, with compactness, precision, and low ripple as desired characteristics.

Why were two sets of circuit boards with two-layer and four-layer stacks ordered for the project?

Two sets of boards were ordered to test the schematics; a four-layer stack was chosen to reduce potential problems and improve track isolation, though not because a two-layer stack was insufficient.

What is the role of a shunt, comparator, diode, and an additional DAC in the module's current control?

The shunt measures current flow, the comparator turns off the power part if the current exceeds a threshold, the diode prevents feedback interference, and the additional DAC provides a reference voltage for precise current control.

What is the significance of using an INA226 for feedback in the project?

The INA226 is used for precise feedback, allowing for accurate voltage control across the output range, especially when combined with RC circuits to reduce noise.

How does the prototype handle voltage and current calibration for accuracy?

Calibration involves measuring resistors in the feedback loop, reference voltages, and adjusting constants in the system to achieve accurate output voltage and current, indicating a complex process involving multiple factors.

What approach is taken to limit the output current in the module?

The module employs a simple method using Ohm's Law to calculate the necessary DAC value for the desired current limit, with the option to use a PID-like regulator for more precise control.

How does the module's design address thermal management and safety concerns?

The module uses a large additional polygon for cooling and a four-layer board design for better heat dissipation. However, it's mentioned that operating at high currents (above 4A) could be unsafe due to high temperatures reached by the XL component.