Activity for Nick Alexeev
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Edit | Post #296658 | Initial revision | — | 5 days ago |
| Question | — |
Is the two-clock start-up technique common these days? Is the two-clock start-up technique common these days? Came across a low power technique for microcontrollers. A crystal may take few hundred milliseconds to start up. The MCU is consuming power, and not executing instructions during that time. Imagine a situation where an MCU is in cyclic sl... (more) |
— | 5 days ago |
| Comment | Post #288844 |
The goal of this JFET circuit is to have a fast op-amp with low input bias current. Another way to achieve the same goal is to use compound (TIA). The first op-amp is chosen for low input bias current and low noise. It could be a FET op-amp. The second op-amp is chosen for high bandwidth. It... (more) |
— | 5 days ago |
| Comment | Post #296601 |
The answer to the general question about how to propagate error information is a book chapter https://preschern.azurewebsites.net/2019-error-codes.pdf The rest of the book is here: https://preschern.azurewebsites.net . Preschern's C papers got compiled into the book [Fluent C](https://www.goodr... (more) |
— | 21 days ago |
| Edit | Post #296576 |
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— | 27 days ago |
| Edit | Post #296578 |
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— | 28 days ago |
| Edit | Post #296578 |
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— | 28 days ago |
| Edit | Post #296578 | Initial revision | — | 28 days ago |
| Answer | — |
A: What exactly is a HAL and how would I write my own? > So is a HAL really just a collection of functions that when called set/reset specific register bits for my specific microcontroller? The HAL created by ST for the STM32 is a relatively thin wrapper around registers. Most functions access a register (or a few related registers) and perform som... (more) |
— | 28 days ago |
| Edit | Post #296478 |
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— | about 1 month ago |
| Edit | Post #296475 |
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— | about 1 month ago |
| Edit | Post #296478 | Initial revision | — | about 1 month ago |
| Answer | — |
A: Communication with microcontroller via usart - using strings a good idea? Command protocols which use strings are a norm. They use more bytes compared to binary protocols, but they are human readable. If the UART itself isn’t a bottleneck, then command strings are a good choice. Some examples of mainstream protocols which send ASCII strings: NMEA 0183 and SCPI. The... (more) |
— | about 1 month ago |
| Edit | Post #296387 |
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— | about 2 months ago |
| Edit | Post #296387 |
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— | about 2 months ago |
| Comment | Post #296387 |
Ankit, is the via going to be filled with epoxy and plated over? Or, is it going to be filled with copper? Or is it going to be a simple unfilled hole in a pad? Is it going to be tented on the other side (opposite side from the pad)? [The words via in pad get misused sometimes, unfortunately.] (more) |
— | 2 months ago |
| Edit | Post #295804 |
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— | 2 months ago |
| Comment | Post #296357 |
If you add an oscilloscope shot of your square wave, that would improve the question. How much noise and overshoot is there? If you don't have the hardware which generates the square wave, then we'll make do without the oscilloscope shot. We can imagine a 1 kHz 10% duty cycle square wave with ... (more) |
— | 2 months ago |
| Edit | Post #296339 | Initial revision | — | 2 months ago |
| Question | — |
Does output impedance of the unbuffered DAC in STM32G4 vary [appreciably] with code? Does output impedance of the DAC in STM32G4 vary appreciably with code? The built-in DAC buffer will be disabled. The datasheet gives only one value for DAC output impedance (section 5.3.20 on page 153). That alone should be enough to conclude that it’s constant vs. code. the line about D... (more) |
— | 2 months ago |
| Edit | Post #296303 |
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— | 3 months ago |
| Edit | Post #296303 |
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— | 3 months ago |
| Edit | Post #296303 | Initial revision | — | 3 months ago |
| Answer | — |
A: AD5941 GPIO2 cannot act as general-purpose output — any workaround without a board respin? There may be workaround, potentially, although I haven't done it. Neither have I used the AD5941. The GPIO2 has an output function for synchronizing external device. Configure it for synchronization, then set the pin state of GPIO2 through the SYNCEXTDEVICE register. Control the state of GP... (more) |
— | 3 months ago |
| Edit | Post #296269 |
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— | 3 months ago |
| Edit | Post #296269 |
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— | 3 months ago |
| Comment | Post #296270 |
I think that O.P.’s idea about coating was to reduce pollution degree, rather than add insulating material between the problematic pins. If the there would be a sealed void, then inside of it would be pollution degree 1, and the required minimum distance would be smaller. (more) |
— | 3 months ago |
| Comment | Post #296270 |
Underfill can be applied on one side of the chip and get pulled by capillary tension all the way across. It looks like there’s no method of inspecting underfill for voids which would be compatible with PCB assembly. Here’s a paper which goes through test methods [Underfill inspection and testin... (more) |
— | 3 months ago |
| Comment | Post #296269 |
When we did it for mains voltage and Molex KK 396 connector, we certified the product at UL. It passed. This was around 2007. If yours is a question of compliance, then make sure to post it to your certifying body. (more) |
— | 3 months ago |
| Comment | Post #296270 |
Underfill under BGA is an established procedure. The underfill compound is wicked under the BGA by capillary action. Here's a [video by Henkel](https://www.youtube.com/watch?v=zSmr2Tv2NsU), [this too](https://www.youtube.com/watch?v=hdxjWJ2c0ao). It got to a point where chip-scale BGAs require... (more) |
— | 3 months ago |
| Comment | Post #296269 |
I don't have a reference. (more) |
— | 3 months ago |
| Edit | Post #296269 | Initial revision | — | 3 months ago |
| Answer | — |
A: Is it allowed to skip a pin to increase creepage distance? [ If this is a certification and compliance matter, then you should run your question and your findings by your test lab, certifying body, specialist safety reviwer. ] Gaps on either side of a floating pin count towards creepage. I've seen it done when Molex KK 396 connector carries mains AC ... (more) |
— | 3 months ago |
| Edit | Post #286766 |
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— | 4 months ago |
| Edit | Post #286766 |
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— | 4 months ago |
| Edit | Post #296050 | Initial revision | — | 5 months ago |
| Answer | — |
A: Altium IPC Footprint Options: Which One Should I Choose for Best DFA and Assembly Yield? I normally use the IPC A footprints because they have the largest pads, and they lend themselves to manual rework. I tend to use 0603 for resistors and capacitors. My boards with IPC A are machine-assembled by two PCBA houses. They didn't complain about the footprints. They didn't complain ab... (more) |
— | 5 months ago |
| Comment | Post #295943 |
This question would fly in the EE.Codidact chat on Discord. The room is active in the recent few weeks. (more) |
— | 5 months ago |
| Edit | Post #295943 | Question closed | — | 5 months ago |
| Edit | Post #295945 | Initial revision | — | 5 months ago |
| Answer | — |
A: Safe handling of residue from old consumer batteries Here's a PSDS (safety datasheet) for Panasonic alkaline batteries. > excerpt from PSDS for an alkaline battery "GHS classification: not applicable" means that it isn't classified as hazardous. If you look at the ingredients, there are no terrible heavy metals like cadmium, lead, mercury. (more) |
— | 5 months ago |
| Edit | Post #295943 | Question reopened | — | 5 months ago |
| Comment | Post #295943 |
[close comment] The EE.Codidact board is about electrical and electronic design. This question isn't about design. (more) |
— | 5 months ago |
| Edit | Post #295943 | Question closed | — | 5 months ago |
| Edit | Post #295823 |
Post edited: added a tip in a post scriptum |
— | 6 months ago |
| Edit | Post #295823 | Initial revision | — | 6 months ago |
| Answer | — |
A: Assembly challenges for shared pad between mounting hole and resistor Here's how I usually lay out optional grounding through a mounting hole. The connections are wide copper pours which reduces the connection inductance. Multiple vias to GND also reduce inductance. One may have insights about the EMC, but one doesn't really know until one tests. Optional ear... (more) |
— | 6 months ago |
| Comment | Post #295485 |
At a risk of attracting SOT identification questions, we can start our own look-up catalog on EE.Codidact . (more) |
— | 7 months ago |
| Comment | Post #295485 |
There's no method that doesn't rely on luck for finding the full part number. There are look-up pages like [this one](https://www.pic-control.com/sot23-marking-code) or [this one](http://www.smdmark.com/en-US/smd-code-R12.html). [The second one baits you to sign-up. Yuck.] (more) |
— | 7 months ago |
| Edit | Post #295403 |
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— | 7 months ago |