Activity for Nick Alexeev
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Comment | Post #293118 |
A few years ago I was hired to help with a project. Towards the end of the project of course, as is typical for war stories. The circuit had an external watchdog timer (reset supervisor IC) which was fed from the I2C clock line. The engineer who designed the board ran out of GPIO pins and decided ... (more) |
— | about 19 hours ago |
| Edit | Post #293118 |
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— | 4 days ago |
| Edit | Post #293008 |
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— | 28 days ago |
| Edit | Post #293009 |
Post edited: added schematic snippet |
— | 28 days ago |
| Edit | Post #293009 | Initial revision | — | 28 days ago |
| Answer | — |
A: Photodiode transimpedance amplifier with single supply synopsis Achievable by using a rail-to-rail op-amp. A small bias on the non-inverting input improves the transient response of the op-amp. That’s the second circuit in the O.P. I use such topology myself for sensing flashing light, as well as steady ambient light. TIA op-amp with non-inver... (more) |
— | 28 days ago |
| Edit | Post #292909 |
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— | about 1 month ago |
| Edit | Post #292898 |
Post edited: update which was posted as an answer converted into an edit of the question |
— | about 1 month ago |
| Edit | Post #292909 |
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— | about 2 months ago |
| Edit | Post #292909 |
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— | about 2 months ago |
| Edit | Post #292898 |
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— | about 2 months ago |
| Edit | Post #292909 | Initial revision | — | about 2 months ago |
| Answer | — |
A: OPA2211 datasheet discrepancy The 1st page of a datasheet is written by marketing. It can still give you an idea of what the chip is about, but it often contains the performance data under the best conditions. The conditions are rarely specified on the 1st page. Always check the electrical characteristics section and the cha... (more) |
— | about 2 months ago |
| Edit | Post #292872 |
Post edited: new tags added |
— | about 2 months ago |
| Comment | Post #292527 |
@#56656 Are you certain that you have pollution level 1, and not 2 ? Pollution level 1 is a sealed enclosure. Pollution level 2 is a PCB in a vented enclosure under room conditions (say a motherboard in a desktop PC). Pollution level 2 is the default when you have neither aggravating factors nor ... (more) |
— | 3 months ago |
| Comment | Post #292525 |
I doubt that these connectors are intended for scenarios where center conductor and shied are on opposite sides of basic insulation. Just like there's no IEC basic insulation in the USB or HDMI jack. What kinds of signals are you going to run through these coaxes? If you'd like further analysis on... (more) |
— | 3 months ago |
| Edit | Post #292378 | Question closed | — | 4 months ago |
| Comment | Post #292295 |
Welcome to EE.Codidact . Out of curiosity, which book is this circuit from? (more) |
— | 4 months ago |
| Edit | Post #292295 |
Post edited: |
— | 4 months ago |
| Comment | Post #292235 |
Let's look at your situation more broadly. Are you making a one-off for your own home use? Or it this going to be a production run? Or something more exotic? (more) |
— | 4 months ago |
| Comment | Post #292235 |
I'd say that the laptop was certified as a system: its case, antenna, and all. If you replace the antenna with something that's not an official replacement part or an accessory released by the maker of the laptop, that would void the certification. It's possible to take FCC certified parts and some... (more) |
— | 4 months ago |
| Comment | Post #292235 |
You're going to void the FCC certification which the original laptop had. (more) |
— | 4 months ago |
| Edit | Post #292133 | Initial revision | — | 5 months ago |
| Answer | — |
A: Purpose of resistance between SENSE/FORCE line of power supply > Furthermore, an amplifier symbol called "gm" is labeled as transconductor. What does it do? Transconductors are voltage-controlled current sources, but what are they doing here? The diagram looks like a voltage output power supply. I'll make a working assumption that it's voltage output power s... (more) |
— | 5 months ago |
| Comment | Post #292131 |
Could you edit your post, and add a link to the manual (or the datasheet, or the product page), please? (more) |
— | 5 months ago |
| Comment | Post #292080 |
Are you designing the entire system? Or are you plugging into an existing system? A lot of systems have a periodic "heartbeat" message on the CAN bus. When your PIC sees the message then it knows it's connected to CAN. (more) |
— | 5 months ago |
| Edit | Post #292007 |
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— | 5 months ago |
| Edit | Post #292007 |
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— | 5 months ago |
| Edit | Post #292007 | Initial revision | — | 5 months ago |
| Answer | — |
A: STM32. What should be done in firmware for VBUS detection through a GPIO pin? I've found a solution, and tested it. What @Olin wrote earlier holds. This is to post my code for STM32. > Does the VBUS detection have to be done in an interrupt? I've asked the ST's technical support, and they replied that it should be done in the interrupt. Here's my ISR code. / ... (more) |
— | 5 months ago |
| Comment | Post #291971 |
Already a useful article.
- You could mention that some MCUs have pins which modify how the MCU received the firmware from the ICD and runs it.
-- STM32 have bootloader enable pins BOOT0 and BOOT1. Their behavior and default state varies slightly from sub-family to sub-family (it's described i... (more) |
— | 5 months ago |
| Edit | Post #291935 |
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— | 6 months ago |
| Edit | Post #291935 |
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— | 6 months ago |
| Edit | Post #291935 |
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— | 6 months ago |
| Edit | Post #291935 |
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— | 6 months ago |
| Edit | Post #291935 | Initial revision | — | 6 months ago |
| Answer | — |
A: Are LDOs more efficient than switching regulators in very low currents? The efficiency of the LDO is a function of the input and output voltages. $$\eta = \frac {P{out}} {P{in}} = \frac {I{out} V{out}} {I{in} V{in}}$$ $I{out} \approx I{in}$ for a series linear regulator ¹ ². Input and output currents cancel. $$\eta \approx \frac {V{out}} {V{in}}$$ In your ... (more) |
— | 6 months ago |
| Edit | Post #291838 |
Post edited: |
— | 6 months ago |
| Comment | Post #291833 |
@#53469 Nice app note. It's the answer to the question. (more) |
— | 6 months ago |
| Edit | Post #291838 | Initial revision | — | 6 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) |
— | 6 months ago |
| Edit | Post #291833 |
Post edited: Copy and paste datasheet excerpts instead of posting screenshots as images. Text is searheable, screenshots aren't. |
— | 6 months ago |
| Edit | Post #291709 |
Post edited: |
— | 6 months ago |
| Edit | Post #291709 | Initial revision | — | 6 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) |
— | 6 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) |
— | 7 months ago |
| Edit | Post #291385 |
Post edited: Fixed spelling in the title. |
— | 7 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) |
— | 7 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) |
— | 8 months ago |
| Edit | Post #290231 | Post undeleted | — | 8 months ago |