Проектируем цифровой DC-DC с контролем тока и напряжения!

Заметки Ардуинщика

23 Jan 202413:17

Summary

TLDRIn 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.

Outlines

00:00

🔧 Introduction to a Collaborative Arduino Project

The video begins by welcoming viewers to the Arduino hobbyist channel and dives straight into the continuation of a project exploring DC-DC converters. The host encourages audience participation in the project's development through comments and mentions that source links are available in the video description. The project, which started over a year ago using a DAC and comparator, has led to a collaborative effort to create a more refined prototype. The host reveals that for testing the circuit design, two sets of PCBs were ordered with both dual and quad-layer stacks, emphasizing the benefits of using a debit card that offers cashback and special offers. The introduction sets the stage for a detailed exploration of a digitally controlled DC-DC converter, its design challenges, and potential applications in automation, testing, and power supply creation.

05:00

🔬 Technical Deep Dive into the Prototype Design

This section provides an in-depth look at the technical aspects of the prototype design for a digitally controlled DC-DC converter. The host explains the initial goal of creating a module capable of delivering up to 24V and 4A, focusing on compactness, precision, and low ripple. A more complex but suitable topology was chosen, and viewers are directed to another channel for a detailed explanation. Using the XEL405 chip and additional components like a DAC and comparator, the video explains how these elements work together to control output voltage and current with high precision. The assembly process is shared, including a preference for soldering without paste and using a budget-friendly soldering station. The host demonstrates initial tests and approaches to accurately set the desired output voltage and current, highlighting the challenges of achieving precise control without feedback. The segment concludes with a discussion on the PCB design, emphasizing the benefits of a four-layer board for minimizing potential issues and improving signal isolation.

10:02

📊 Performance Evaluation and Future Improvements

The final segment evaluates the prototype's performance, including its current stabilization capabilities and temperature management under load. Surprisingly, current stabilization does not significantly increase output ripple, and the prototype effectively limits current, making it suitable for powering LEDs or charging batteries. However, the highest temperature reached by the converter suggests caution at higher currents. The video concludes with thoughts on the prototype's topology and feedback loop's response times, indicating plans to improve future versions by integrating an STM32 microcontroller for better efficiency and cost-effectiveness. The creator expresses a desire to further refine the design, hinting at future projects and encouraging viewer feedback. This segment wraps up the presentation by showcasing the practical outcomes of the project and setting the stage for ongoing development.

Mindmap

Keywords

💡DC-DC converter

A DC-DC converter is an electronic circuit that converts a source of direct current (DC) from one voltage level to another. It is a key component of the project discussed in the video, which involves designing and testing a digitally controlled DC-DC converter module. The converter's ability to accurately regulate voltage and current output is central to the video's theme.

💡Feedback

Feedback refers to sending a portion of the output signal back to the input. The video describes using feedback from the DC-DC converter's output voltage to precisely control the output. This feedback loop enables closed-loop regulation of voltage.

💡Current limiting

Current limiting involves restricting the maximum output current of a power supply to prevent damage from overcurrent conditions. The video demonstrates digitally programmable current limiting in the DC-DC converter by controlling the feedback threshold.

💡Microcontroller

A microcontroller is a small computer on a single integrated circuit. The video mentions using a microcontroller (such as an STM32) to replace the analog components and implement more advanced control algorithms for the DC-DC converter.

💡Switching regulator

A switching regulator converts power efficiently by rapidly switching between different circuit modes. The DC-DC converter circuit in the video is a type of switching regulator topology called a buck converter.

💡PWM

PWM (pulse width modulation) refers to the rapid on-off switching that controls power in a switching regulator. The converter's output voltage is regulated by varying the duty cycle of PWM signals.

💡Ripple

Ripple refers to small periodic variations in the DC output voltage due to imperfect filtering of the PWM switching. The video examines ripple levels and mentions using an LC filter to reduce ripple.

💡Thermal management

Thermal management involves controlling heat in electronics to avoid overheating failures. The video checks converter temperatures and notes the importance of thermal management at high currents.

💡Feedback loop

A feedback loop routes a system's output back to its input to enable self-correction. The converter uses voltage and current feedback loops to precisely regulate its outputs.

💡Control algorithm

A control algorithm is a computational procedure that automatically adjusts system behavior. The video discusses implementing advanced control algorithms on a microcontroller to enhance the converter's performance.

Highlights

The study found a significant increase in life satisfaction for participants after the mindfulness training program.

MRI scans showed changes in brain structure and activity patterns in regions related to awareness, empathy, and stress.

Participants reported feeling more present, less judgmental, and better able to cope with negative emotions after 8 weeks of practice.

Mindfulness practices helped reduce feelings of loneliness and social isolation in older adults.

The control group that did not receive mindfulness training showed no significant changes.

Mindfulness meditation led to declines in inflammatory gene expression and markers of cellular aging.

Compassion training increased activity in brain regions involved in understanding others' mental states.

Mindfulness interventions improved sleep quality, duration, and efficiency.

Mindfulness reduced stress, anxiety, and depression symptoms in patients with chronic illness.

The study provides evidence that mindfulness can change brain function and structure.

Mindfulness training shows promise as an adjunct treatment for substance use disorders.

Participants were able to sustain attention and awareness during meditation after 8 weeks of training.

Mindfulness practice led to significant increases in working memory capacity.

Compassion meditation increased altruistic behaviors towards strangers.

More research with larger sample sizes is needed to confirm the findings.