Tag: microcontroller

Where is the ADC? RIGOL DM858 Teardown | Voltlog #486

Ever wondered what lies beneath the sleek exterior of the high-tech Rigol DM858 multimeter? In a recent teardown video, we took a deep dive into the inner workings of this precision instrument, uncovering the components that make it tick. Right off the bat, the teardown revealed the beautiful construction and assembly quality, with key areas like power supplies, connectivity, and a clever system-on-module design.

The power supply section was straightforward, with a USB-C input and a series of switchers to step down the voltage to the required levels. The real star of the show was the SODIMM module, housing an Allwinner A40i-H quad-core Cortex-A7 processor, RAM chips, flash memory, and a power management circuit.

This modular design offers several advantages, including cost savings, flexibility, and the ability to swap out components as needed. Moving on to the input section, we encountered a curious square PCB module housing the user-accessible fuse and input protection components like gas discharge tubes, Metal Oxide Varistors, and clamping devices.

Underneath a small shield, we found relays likely responsible for input switching and range selection. One of the most intriguing discoveries was the potential use of the microcontroller’s built-in ADC (Analog-to-Digital Converter) instead of a dedicated ADC chip. This design choice, if true, would be a clever solution for high sampling rates and accurate measurements.

However, not all mysteries were solved. We encountered a few unidentified components, leaving us scratching our heads. Can you help shed light on these enigmatic parts? Leave a comment below and join the discussion!

InTheMail | Voltlog #482

Welcome to another exciting InTheMail unboxing extravaganza! In this episode, we dive into a treasure trove of gadgets, tools, and components perfect for any electronics tinkerer or maker. From mechanical fasteners and wiring accessories to unique finds like magnetic multimeter leads and a PoE detector, this mailbag is brimming with surprises.

One highlight is the heartwarming story of upgrading a toy excavator for a 2-year-old construction machinery enthusiast. By incorporating LEDs, sound effects, and vibrations, an ordinary toy was transformed into an interactive delight, sparking joy and wonder. This project showcases the magic of combining electronics with creativity.

Another intriguing item is the set of sodium-ion 18650 batteries. While still in the early stages of adoption, these safer and longer-lasting alternatives to lithium-ion batteries hold promise for future designs. The possibility of destructive testing (with caution, of course) adds an element of excitement and curiosity.

From essential components like standoffs and screws to specialized tools like the drain cleaning brush and countdown timer, this mailbag caters to a wide range of needs. Whether you’re prototyping, repairing, or simply exploring new technologies, there’s something for everyone. So, join us on this adventure as we unbox, explore, and dream up new projects with the latest additions to our ever-growing collection of electronics goodies.

Voltlog #254 – Epaper Display Pixel vs Segment Type

Welcome to a new voltlog, today we’ll have a little chat on epaper displays. You probably saw this post I made to my youtube community page a few days ago, it was about my epaper thermometer which suddenly showed the low battery sign and stopped working. I’ve only had this running for 1 month, when I received it, the battery was not connected so I thought it must have been an old battery or a bad one.

Voltlog #249 – Making Some USB Serial Converter Boards With CH340E (part 1)

Welcome to a new video, today I’m building a bunch of usb to serial converter boards because if you are into electronics and microcontrollers you will for sure need a bunch of usb to serial converters to connect your boards to a computer for example.

The idea for building these boards started when I found the CH340E converter chip on aliexpress, I like several things about this chip, it was small because it comes in MSOP10 package, it was cheap at about $0.40 a piece and it requires minimal external circuitry, in fact it only needs an external bypass cap.

Voltlog #127 – 0-60V 0-10A 1mV 1mA Panel Meter Review

So I discovered this module a few months ago and it’s been sitting in a box since then, I almost forgot about it, until a few days ago when I decided it will be a good idea to do a video on the subject.

Let me give you a few details on the specs of this module and as usual it’s pretty difficult to find the information as it’s the case with every new module coming out of China. First of all we have an input range of 0-60V and 0-10A and a 5V rail is needed to power the module itself. It has a voltage measuring accuracy of ±0.2% + 0.2% full scale which sounds strange because these figures are usually given in a percentage plus or minus a number of least significant digits. The current measuring accuracy is ±0.4% + 0.3% full scale.

The meter is basically capable of measuring with a resolution of 1mv and 1mA (however the accuracy is quite bad, as shown in the video) which is quite nice and useful (not really useful with bad accuracy) for projects like DIY power supplies or DIY electronic loads. It can also display the power in watts with a resolution of 1mW as well as showing the load impedance.

Here are some links to this product: