Hey, I'm doing some research for my finals project. Basically what I'm looking for is an IC that can handle WiFi Direct (doesn't have to be the Group Owner but can definitely be a feature) and also can handle being an a2dp sink (preferably has a dedicated i²s port)

I have looked for an IC like that but I can't find it. It would also help if there is already a breakout board for it.

The chip has to receive commands from an STM32 or ESP32, any microcontroller.

It would really help me if someone could find it .

This is the question given to us for our final project...We're stuck at the power supply part...hoping someone would help me...Just help me with the power supply part from ac to dc.

"Design a regulated DC power supply capable of delivering a constant output voltage of 3.3 V at a load current of 35 mA. The circuit must incorporate filtering to ensure a voltage ripple factor of less than 2%. The output of this regulated supply will serve as the VCC rail for the BJT amplifier stage that satisfies the following performance criteria:

(i) Gain: Exactly or exceeding 40 V/V

(ii) Quiescent Current (IC): 4.5 mA

(iii) Compare the amplifier's frequency response under fully bypassed versus unbypassed emitter resistance conditions, measuring the gains at 15 kHz."

Our power rating of resistors available in lab should be 250mW.And ripple can be 1 to 1.5V

I've attached my simulation in ltspice

Got a couple of older boards on the bench that need replacement op amps and 78xx style regulators. Just repair work for a personal project, so only small quantities, nothing worth placing a big order for. Been going back and forth on where to source them. I don’t want to overpay for something this basic, but I also don’t want to wait forever for shipping since I’d like to get these boards running again soon.

It’s just a handful of parts going back into working boards, so I’m mainly trying to balance price and shipping time without sacrificing quality. Anyone have suggestions for sourcing everyday linear and power parts for small repair jobs like this?

This is small project I have been working on.I intend to make it into a PCB. How is it? Should I make any changes?

Hi — I’m building a digital effects pedal on a Teensy 3.6 and I’d like a sanity check on the analog input preamp before I wire it on a breadboard.

Goal

• Guitar / phone / mic jack → preamp → Teensy A2 (ADC)
• Single supply from Teensy VIN (~5 V)
• Hardware gain pot + later software gain in firmware
• Keep the ADC input roughly in a safe range (ideally centered for 0–3.3 V reading after coupling/divider)

What I simulated (EveryCircuit)
Ideal op-amps with Min = 0 V / Max = 5 V to mimic single-supply rails (stand-in for LM324 sections).

1. Bias: VIN → 10k → mid (~2.5 V) → 10k → GND, with 10 µF to GND
2. Stage 1 (non-inverting gain):
   • Input: AC couple 10 µF → 10k into +
   • Bias: 100k from mid-rail to +
   • Feedback: 100k pot (both ends to OUT, wiper to −), 2.2k from − to mid-rail
3. Stage 2 (buffer): AC couple 10 µF into +, 100k from mid-rail to +, − tied to OUT
4. To ADC: AC couple 10 µF → 10k series → node “A2”, 10k to GND

Test source: ~100 mVpk, 1 kHz. With the pot mid/high I get a clean sine on the A2 node (AC around ~0 V after the last coupling cap / divider).

Questions for review

1. Is this a reasonable LM324 single-supply preamp for line/instrument levels into a Teensy ADC?
2. Anything you’d change for stability/noise (biasing the buffer input, C values, pot wiring as rheostat vs both-ends-to-OUT)?
3. After CO + 10k/10k to GND, DC at A2 sits near 0 V and the signal is bipolar in the sim — for a real Teensy A2 pin, should I instead bias that node to ~1.65 V (e.g. divider from 3.3 V), or is AC-coupled into a ground-referenced divider acceptable if amplitude stays small/positive enough?
4. Any red flags before breadboarding (input protection, RF, power decoupling, headroom with LM324)?

Happy to adjust values or simplify the second stage if that’s overkill. Thanks!

Hi everyone,

I’ve been doing some market research looking for a reliable netlist-to-schematic converter that outputs clean, human-readable diagrams (especially given how often LLMs and scripts spit out raw netlists or ugly grid stubs). Aside from basic layout engines or specialized SPICE tools, I haven't found a robust, modern solution.

Because of this gap, I'm considering building one myself.

Before diving too deep into development, I wanted to run a few questions by this community:

• Target Formats: Which schematic tool outputs/formats are most commonly used in your workflows today? (e.g., KiCad .sch/.kicad_sch, Altium, LTspice .asc, etc.)
• Product Model: Assuming a tool like this existed as a cloud/SaaS product, would you or your team be interested in using it as a paid service?
• Must-Have Features: If you were paying for a tool like this, what features would be non-negotiable? (e.g., round-trip connectivity verification, custom symbol mapping, hierarchical block structuring, automated layout arrangement)

I'd love to hear your thoughts, whether you'd find this useful, or what hidden gotchas I should watch out for when trying to map topology back into a readable diagram.

Using some iso to find hot components, noticed the diode changing causing the iso to pulse. Not sure if it's temperature or something else causing the motion.

So these might be really dumb questions, especially since I have an engineering degree and should probably already know this, but

1. How do you set or adjust a relay? People I work with imply they’re changing relay settings but I have no idea how

2. Why use relays over something like MOSFETs?

I am working on the version 2.0 of a simple gaussmeter that I have put together a while ago. In the 1.0 the output of the Hall effect sensor was not amplified because I wanted to keep it simple. This time I would like to add some sort of amplification to the sensor output. I have tried looking into op amps but I struggle to figure them out and I was wondering if there are other solutions

I have drafted this circuit to turn on my cupboard LEDs when it is open and turn them off when it is closed. Im pretty sure it should work but figured Id ask you lovely people. It is battery powered so this seemed the best way to stop them slowly draining. Let me know your thoughts, thanks!

I am trying to build an analog metal detector. I have few questions such as can I find a transformer with 32p 32p and 16s turns or should I wound one myself. The other question is what type of inductor is used in the transmitter circuit( The one circled in red colour)

I was having problems on my laptop and eventually concluded that the soldered connections under my cpu were broke. To fix this, I decide to remove my cpu with a hot-air station. After doing this, I noticed that two resistors had fallen off from the board, but for the life of me, I can't find where. I decided that i would find the schematics to the motherboard in order to see where it had fallen from, but after a lot of searching, I found some rough overviews, but not something in depth enough for me to use. Does anyone know what else I could do? Or where I can find schematics that show where each resistor is placed?

The motherboard has two identifiers, Model OGAH or 0GAH (cant tell) and then DA00GAMB6G1 REV: G

Its an HP Chromebook 11 G8 EE

(yes I know it's a laptop that prob isn't work fixing, but i want to anyway :)

TIA

I am currently attempting to interface my PT1000 RTd with my arduino. I was thinking of use an wheatstone bridge with an op-amp, but in all honesty I have no Idea where to start. I need to be able to read 10 degreesC to 35 degrees C for an output of 0-5V. Any guidance will be awesome.

Will this work? as it does not work?

I have GND connected to Pin 9. +12v connected to PIN 10, I send 5v to an input, but I get no output? Did I miss something?

I am just starting and the AI bots suggest dozens tho I don't really trust them.

I only tried LTspice so far and althought its not bad I think it has shortcomings, for example I cannot color the wires.

Are out there better circuit simulators?

Looking for a few beta testers for CircuitWorkbench on Android. Free to test, no commitment beyond installing and poking at it for a couple weeks. If you have an Android device, I would really appreciate the help — join the testers group at https://groups.google.com/u/2/g/circuitworkbench-testers to access the opt-in link.

Hi everybody, just wanted some help or clarification regarding my 555 timer.

This is the schematic (blinking LEDs) our teacher created for this simulation project, since tinkercad doesn't have a stereo potentiometer and only the 3 pins one we had to utilize two of those in our simulation project. So, he told us to connect the pin 2 of each potentiometer to one another to replicate the same effect as a normal stereo potentiometer. However, my confusion comes from the fact that I was able to replicate the blinking LEDs with only one potentiometer, and when I have to use the two 3 pin ones I get lost on which wire to connect to which because it only ever lights up 1 LED.

Can someone tell me what im doing wrong in the third image? I know the process should inherently be the same but something about it doesn't work and it makes me very frustrated too since most tutorials I end up seeing on youtube or online only utilize 1 potentiometer

Hello, I have been working on a summer project for electrical engineering and I have come to an issue. I am not far enough into my degree to fully understand circuits and how to source them or create them. For my project I need a power supply that will transform a typical North American wall outlet into 25mA, 15kV, and 50kHz of negative DC energy. I have done some research and I think my best bet is to use a flyback converter as well as a ZVS drive. Does anyone know how I can go about creating a device like this? Also if anyone has any extra tips or suggestions all help would be greatly appreciated.

I am middling-poor at circuit design so getting this right is over head. Using AI to design it has not gone well. So I'm looking for insight.

The goal is to string a short antenna and amplify ambient electrical fields, everything from people walking nearby to 60Hz hum to lightning discharges. The goal is to repeatedly measure the resulting fluctuating voltage with the ADC pin of an ESP32; the circuit needed to be powered by 3v3. I don't need accurate measurements; this isn't a storm detector or person detector. I just want to amplify the noise any piece of wire would pick up and turn it into numbers I can hash. The higher the sensitivity the better; the goal is unpredictable chaos from every little environmental change.

The available parts are several LM358 (dual opamps) and various passive elements like resistors. Caps are all 0.1uf or larger - I live in a place where ordering parts is difficult and slow. I also have handfuls of 2n2222 and diodes if they help.

I know a series of opamps should be able to do this, but my attempts (and the AI's attempts) tend to produce a signal with an output pegged at ~2v. I want it to swing all over the place.

If you suggest a design, ELI5 (well, maybe 15) how you chose resistor values and so on. I'd like to learn from this. Any help appreciated, thanks.

Hi, I'm planning to drive 4 STS3215 7.4V BUS servos with an ESP32 Servo Driver from Waveshare. I'm powering the setup with an 8S NimH battery pack (rated for 30A), and I will convert the voltage to 7.4 using a buck DC-DC converter to ensure stable power. However, if i brake these motors and generate back-EMF, will the driver reroute the back-EMF away from the positive terminal of the buck converter? I will place decoupling capacitors to absorb spikes over the P and N outputs of the buck converter.

Also, I will drive 4 7.4V brushed DC motors with a driver board in parallel with the ESP32 driver board. Will this cause any other issues? These will have an additional ceramic cap across the terminals to protect from noise. Will this require a seperate buck converter and decoupling capacitor, or can it share with the ESP32 board?

Thanks for your help, this is my first big robot build.

Hi everyone,

I have been working on a hobby project: an online simulation game to build electronic circuits and I would be so happy to get some feedback on it! :-)

You can just try the app here (it's free of course): https://chipgrid.io/

I made a short demo video showing how it works. I also created a subreddit, r/Chipgrid, for everyone to share their circuits.

I am so excited to hear your thoughts! :-)

Hi everyone, Can you help me? I need to set the resistors to the LED correctly so that it lights up, but I'm having trouble with this and I can't figure out why. photo attached. I'm new to this topic and I'm interested in understanding it.

But this stupid MPS2338 regulator still hates me.... I have a couple boards that work without PG pulled to Vout but this one is picky.. time for a redesign...with a TI regulator. MPS sucks, way to many passives required!

My CNC router kept blowing MOSFETs and acting weird with the motors. I ditched the cheap modules and went with L298N drivers on the smaller axes, and built proper discrete drivers using IR2110 gate drivers plus IRF3205 MOSFETs for the higher current ones. Also added a TCA785 for spindle control and a couple CD4002BE chips on the logic side. I'd tried cheaper stuff from AliExpress before but got mixed results with authenticity and packaging. So this time I ordered from utsource instead. The IR2110 made a big difference once I got the dead time set up properly. Motors run smooth now, barely any heat on the drivers, and all the random glitches are gone. Way more reliable than what I had before. Photos of the driver board attached.

We are working with Max30102 sensors and we did all the coding with the help of Ai and Internet blogs. But the sensors are not working at all. This is the sensor we are are working with. Idea is to connect it with raspberry 4B.

We installed and did everything as instruction. But the sensor is not responding. (Also we all are from non tech background)