Activity for Nick Alexeev
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Edit | Post #291838 |
Post edited: |
— | 9 months ago |
| Comment | Post #291833 |
@#53469 Nice app note. It's the answer to the question. (more) |
— | 9 months ago |
| Edit | Post #291838 | Initial revision | — | 9 months ago |
| Answer | — |
A: Using only ceramic capacitors on an input of an SMPS - unclear advice from manufacturer The electrolytic capacitor acts as a snubber in parallel with the ceramic capacitors. If one were to design an RC snubber to dampen the LC circuit, it would have a large capacitance (compared to the ceramic), and some series resistance. An electrolytic capacitor with some ESR is a cheap way to get ... (more) |
— | 9 months ago |
| Edit | Post #291833 |
Post edited: Copy and paste datasheet excerpts instead of posting screenshots as images. Text is searheable, screenshots aren't. |
— | 9 months ago |
| Edit | Post #291709 |
Post edited: |
— | 10 months ago |
| Edit | Post #291709 | Initial revision | — | 10 months ago |
| Question | — |
STM32. What should be done in firmware for VBUS detection through a GPIO pin? I've got a is self-powered USB device, which means that I have to do VBUS detection. The device is built around STM32G474. Unlike some other STM32s, the STM32G4 don't have a dedicated pin for VBUS detection, so I have to do it through a GPIO pin and firmware. VBUS is connected to the GPIO pin PA10 ... (more) |
— | 10 months ago |
| Comment | Post #291671 |
ESD straps have a built-in 1MΩ resistor. [Example.](https://www.mouser.com/datasheet/2/107/TB_S0101-3132271.pdf) (more) |
— | 10 months ago |
| Edit | Post #291385 |
Post edited: Fixed spelling in the title. |
— | 10 months ago |
| Comment | Post #291461 |
@#82425 What's the purpose of this device? What do you ultimately need to accomplish? The question is missing the context. (more) |
— | 11 months ago |
| Comment | Post #291386 |
@#53469 Only the position of the dots relative to each-other matters. If both dots are on the same side, then it's a common mode choke (both on the left side, or both on the right side, doesn't matter which side). If one dot were on the right and another one on the left, then it would be a differe... (more) |
— | 11 months ago |
| Edit | Post #290231 | Post undeleted | — | 11 months ago |
| Edit | Post #290231 | Post deleted | — | 11 months ago |
| Edit | Post #291311 |
Post edited: |
— | 12 months ago |
| Edit | Post #291311 |
Post edited: |
— | 12 months ago |
| Comment | Post #291238 |
Component ID question questions have to meet certain guidelines. Here’s our [present version of the guideline](https://electrical.codidact.com/help/compid). EE.Codidact isn’t inundated by identification and repair questions, and that’s not a bad thing. After some number of such questions accumulat... (more) |
— | 12 months ago |
| Edit | Post #291238 |
Post edited: |
— | 12 months ago |
| Comment | Post #291238 |
@#53279 Check the output of the unidentified 331 chip on the undamaged unit. Probe the voltage at the middle pin, and at the other tantalum capacitor (the East-West one). It may be a boost switcher. That would explain two things: the connection of the inductor, the diode between pins 2 and 3. If... (more) |
— | 12 months ago |
| Comment | Post #291240 |
Yes, that’s a SOT-89. I looked up switch mode regulators [with integrated MOSFET] on DigiKey, and there are none in SOT-89. Maybe it’s a linear regulator, or a transistor. (more) |
— | 12 months ago |
| Comment | Post #291238 |
@#53279 There are two throughole pads south of these parts in this photo. They are marked [-] and [+] in copper. It looks like wires are soldered there. What's the purpose of these terminals? What's connected to them? (more) |
— | 12 months ago |
| Comment | Post #290863 |
Fixing these problems may reverse my downvote. (more) |
— | about 1 year ago |
| Comment | Post #290863 |
Second problem. Your question has to be self-contained. You are referencing another article, and it's lengthy [as much as I like reading Olin's material]. Add a summary, or quote the parts pertinent to your question. Besides, the referenced resource is on another forum. (more) |
— | about 1 year ago |
| Comment | Post #290863 |
First problem schematic is missing. Purpose of the circuit or principles of the operation could have compensated somewhat for the lack of schematic, but those are missing too. (more) |
— | about 1 year ago |
| Comment | Post #290774 |
Monica, your initial hunch that this is a Power User question was right. This is a troubleshooting question in the deep end of Power User. I didn’t bring it up sooner because we're running low on questions at EE.codidact. (more) |
— | about 1 year ago |
| Comment | Post #290774 |
What’s the model of your UPS? If it has a diagnostic output (USB, or serial), then maybe we can glean what it’s thinking. (more) |
— | about 1 year ago |
| Comment | Post #290774 |
Like Olin wrote in his answer, I wouldn’t expect the 5 year old battery in a UPS to be bad, assuming that the UPS runs on battery rarely. But if there was a mains outage every few weeks (or a faulty UPS thought that there was one) for 5 years, then the battery may have worn out. Deep cycle lead-aci... (more) |
— | about 1 year ago |
| Edit | Post #290602 | Initial revision | — | about 1 year ago |
| Answer | — |
A: Level shifting of a 3 state logic pin Another solution which uses an ADC to read the three-state pin on the battery charger IC. The original question mentions GPIO, and doesn’t mention ADC. Maybe this will be useful for some other design which has an ADC. diagram for a level shifter between MCP73831 and a microcontroller with an ADC... (more) |
— | about 1 year ago |
| Comment | Post #290601 |
@#53832 The contact resistance will dwarf the bulk resistance of the pogo pin. Why are you concerned about the pogo pin resistance in the first place? What are you going to use the pogo pin for? (more) |
— | about 1 year ago |
| Comment | Post #288954 |
Did DuckDuckGo approve it? I tried the `!codd` bang DuckDuckGo, but no bangs came up. There's always `site:electrical.codidact.com`, of course. (more) |
— | about 1 year ago |
| Comment | Post #290541 |
@#36396 About availability. I needed an ADuM2250 in 2022. They were out of stock in regular channels for a regular price around 10 USD, and scalpers were asking 200 USD per chip. They are available on regular distributors at the time of writing. (Other IC manufacturers have pin-compatible parts ... (more) |
— | about 1 year ago |
| Comment | Post #290541 |
@#36396 A convenient thing about Analog’s magnetic isolators is that some of them are tailored to standard digital buses. [These ones](https://www.analog.com/en/parametricsearch/11034#/) have a CAN transceiver and an isolator in the same package. CANH and CANL on one side, unidirectional TXD and RX... (more) |
— | about 1 year ago |
| Comment | Post #290357 |
@#53469 Could you describe your entire system please, and the application? Where does the input come from? Where does the output go to? What are you trying to accomplish ultimately? (more) |
— | over 1 year ago |
| Edit | Post #290354 |
Post edited: beautification |
— | over 1 year ago |
| Edit | Post #290334 |
Post edited: |
— | over 1 year ago |
| Edit | Post #290334 |
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— | over 1 year ago |
| Edit | Post #290334 |
Post edited: |
— | over 1 year ago |
| Edit | Post #290334 |
Post edited: |
— | over 1 year ago |
| Edit | Post #290334 | Initial revision | — | over 1 year ago |
| Answer | — |
A: Noise from oscillator on top layer to clock on bottom layer with VCC & GND layers between What you are proposing may be okay (depending on other specifics of the design), but your proposed 4-layer PCB stack-up looks like a compromise. Clock is a high speed signal, and so is SPI depending on the edge raise time. Clock and SPI are on different layers: top and bottom. What acts as referen... (more) |
— | over 1 year ago |
| Edit | Post #290325 |
Post edited: |
— | over 1 year ago |
| Edit | Post #290325 |
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— | over 1 year ago |
| Edit | Post #290325 |
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— | over 1 year ago |
| Edit | Post #290325 |
Post edited: |
— | over 1 year ago |
| Edit | Post #290325 | Initial revision | — | over 1 year ago |
| Answer | — |
A: What fabrication process is being used for jellybean parts [I used to work at Microchip.] > Is it [node size] at all important [for power management ICs] ? For power conversion ICs cutting edge MOSFETs on the scale of 5nm aren't important, because power MOSFETs are large. Larger scale MOSFETs (older generation processes) are cheaper than the cutting ... (more) |
— | over 1 year ago |
| Comment | Post #290324 |
*Jellybean* means industry standard design, multiple suppliers, typically low cost in its class. LTC7880 definitely isn't jellybean, TPS610333 probably isn't jellybean. (more) |
— | over 1 year ago |
| Comment | Post #290284 |
Could the extended settling time be caused by the voltage coefficient in the ceramic capacitor? I'm guessing that your capacitor is X7R or some other Class 2 ceramic, because of its value in the uF range. Try a capacitor with the same Class 2 ceramic, but with a higher voltage rating, and see if th... (more) |
— | over 1 year ago |
| Edit | Post #290231 | Question closed | — | over 1 year ago |