Reddit:Electronics

I was trying to identify some IC's recently and found out that ChatGPT is incredibly good at identifying IC parts from their markings with some extra context information.

It can require some prodding and trial and error and giving it some hints helps e.g. a description about what you think it does, component footprint, visible marking, the device you found it on. and force it to list number of alternatives. You can also give it a picture and let it find the layout context.

Example I was trying to identify the component marked: KP05 5MES. I gave it the picture and the prompt:

""
Help me find this component: The packaging has these markings:
KP05 5MES
It has aSOIC-8 package
It is a high speed component that operates in the GHz range.
Found on the front end of a GigaWave 6400
Give me a list of possible alternatives.

""

One of the suggested components is the MC10EP05 and I could then verify it by looking at the datasheet

That's pretty cool

1206 resistor for scale, and it works! This is a led driver TPS92201a, those legs are now antennas.

A few months back I shared a board I designed here. I loved the support from the community so I will be open sourcing the design for everyone to enjoy this.

Open source link - https://github.com/NoamanKhalil/Keyboard-pico

Thyratron inside a Varian EDGE (linear accelerator).

Not exactly a keyboard, but the plan is to hook this up to a Pi pico whenever it arrives and use it as the F1 - F24 keys for a CCTV project I'm working on as a "Camera Control Panel"

With all the IO ports on a pico I'm pretty sure I could have gave each switch it's own dedicated IO, but this felt more fun lol

Continuing from the idea published a couple of days before - Building a programmable DC-DC Power Supply with I2C Interface (I2C-PPS). Part 1 - Idea.

I decided to get some intuition about overall device structure before gathering its schematics. As I sketched it in the picture the buck-boost converter can be seen as the set of several blocks - a power stage, input and output filters with respective current sensors, a set of programming resistors, a digital I/O plus indication circuit, and a master switch. The power stage consist of 4 power MOSFETs and the inductor. The input and output filters are sets of capacitors mixed with current sensing resistors. The converter's operation mode and HW limits on voltage and current are set by programming resistors. And digital I/O with indication circuit provides interface for RPI and some leds for us - humans. The master switch makes it possible to start or shutdown the thing as it needed independently by RPI as it's needed. Normally, it should stay off and should go off if RPI goes down turning the converter off when input voltage is here without running RPI.

For the switcher TI provides a design calculator in form of an excel spreadsheet and schematic design checklist which allow to select values for main components with desired input and output specs in mind. As for now I decided to go with 4-6V input window but it really should stay at 5V and set HW input and output current limits at 5A. With 250kHz switching frequency many 10uH inductors with Isat > 7A and DCR in recommended range should work along with set of recommended power MOSFETs. More details you can find in the project repo - github.com/condevtion/i2c-pps.

Looks like it's time to pull KiCAD into the project.

Didnt think it was a thing! Would have expected some mandatory SMT ICs

I also wrote about it here https://boxart.lt/en/blog/diy_digital_clock

I was lurking through DigiKey catalog and found a TI buck-boost controller with I²C interface - BQ25758S. The controller allows to create a programmable power supply with quite impressive output specs - voltage 3.3-26V and current up to 20A. Decided to give it a try and create a compact board for my RPI Zero. I don't think I'll go above 3A input (which means only 500mA@26V give or take some efficiency) and it's a bit of a shame that the controller doesn't go below 3.3V (much better would be at least 1.8V). For starter created an umbrella repository - github.com/condevtion/i2c-pps. Any "well, actually" are very welcome!

I really like motorcycles, specially old sports bikes, but, they do come with a terrible thing, they don't have any safety electronics at all, ABS, TCS, nothing, completely barebones, and I consider myself a pretty new rider, so I'm starting a project where I'm gonna make my own traction control, using hall effect sensors and laser cut tone wheels for sensing both of the wheels rotation, so the ESP32 inside the main PCB can do the math, alongside the MPU6050 GY-512, so it correct the "slipage rate" as the bike inclines from side to side into turns in the twisties, it's definitely not gonna be perfect from the get go, but I'm really hopeful that this thing can work properly.

If you're wondering, they don't act directly on the brakes, but rather using the relay to shut off the ignition coil for a few microseconds as the bikes takes grip again, hopefully this will be able to help both me and several other riders ride their dream bikes more safely!

Everything is at a very starting phase, but I did already order all the PCBs from JLCPCB and the components I bought locally, so excited to see how it turns out!

I’d like to share my experience building a "rough gauge" for my LiFePO4 battery pack. Instead of using an off-the-shelf Smart BMS, I chose the DIY route to better understand the underlying physics and processes.

Stock INA226 modules come with a 100 mΩ shunt resistor, which limits the current measurement to a measly 800 mA. This is far too low for a power battery.

• Shunt Replacement: I replaced the stock resistor with a custom 5 mΩ constantan wire shunt. This should theoretically expand the measurement range to 16 A.
• Reinforcement: Since handling 16 A+ is serious business, I added copper shims (8x0.15 mm) and performed heavy tinning to ensure the high current doesn't rely solely on the thin PCB copper foil.
• Hardware: The system is powered by an ESP32 (Cheap Yellow Display - CYD).

To find the exact resistance value, I ran a series of tests and compared the readings with a UNI-T UT61 multi meter. The calculated precision value is 4.392 mΩ.

• Comparison with UT61: https://youtu.be/3OMUGPUffBk
• Accuracy: The deviation from the UT61 is only 30–40 mA at a 10 A load.

The biggest challenge is heat. At currents above 10 A, the shunt begins to warm up noticeably. This creates Therm-EMF (the Seebeck effect), which causes "phantom" readings of about 50 mA on the screen for several minutes after the load is disconnected, until the node cools down.

More details here: https://en.neonhero.dev/2026/02/modifying-ina226-from-08a-to-high-power.html

A long anticipated update for "Silly power supply for a lone lamp" post :)

The original post showed a simple set of low power batteries connected in parallel supplying a 12V/50mA lamp. The schematic featured a diode per battery to prevent them from feeding each other.

Here, I decided to check experimentally if the diodes indeed work as expected. I used an STM32F103 module as multichannel ADC, a set of resistors to scale down from 0-18V to 0-3V and a RPi Zero 2W as a 5V power supply and to collect data. Potentiometers were set to 20k creating 6 100k/20k voltage dividers (pic 3).

First, measured lamp and batteries voltages with a fresh set batteries. They held around 3 hours 45 minutes. The set had voltage around 12.6V fresh without load. Upon switching on the load they immediately dropped to 12V and then spent most of the time going from 10.5 to 8.5V as the pic 4 shows. The diodes took about 350mV so lamp's voltage went clearly below batteries.

Then I mixed 3 fresh and 3 used batteries and actually was really surprised with how clearly it showed when used batteries kicked in. The last pic shows voltage drop across diodes and comparing with the previous one you can see that the diodes for used batteries open as voltage reaches around 200mV. Which is a great real-world demo of how low is cut-in (or knee) voltage for a Schottky diode can be (here SD103A used).

Here’s a decoder I made in my class! It takes the binary inputs from the four switches and uses a seven-segment display to turn them into decimal numbers. Made with a 7447 CMOS IC.

I know it’s very disorganized and I could certainly get better at saving space. I’m still new to building circuits, but I still think it’s really cool!

Thinking of using it for either an induction heater or a dual resonant solid state tesla coil, but next up will be having to deal with annoying gate drive stuff first.

it's displaying GHIJKL on the display. The display is a Maxwell MAX7219 7 segment display run from an ESP8266 generic. I had to write my own driver so I could show what I wanted via the letter and not binary literal. Am I a look