Activity for Olin Lathropâ€
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Edit | Post #286314 |
Post edited: |
— | about 2 years ago |
| Edit | Post #286314 |
Post edited: |
— | about 2 years ago |
| Edit | Post #286314 | Initial revision | — | about 2 years ago |
| Answer | — |
A: How do PLCs normally measure 4-20mA current loops? You should not be relying on the internal circuitry of whatever senses the 4-20 mA current. Note that the two implementations you show both use current sense resistors. The only difference is their value. I have designed several current-sense front ends, although none were inside a PLC. The cus... (more) |
— | about 2 years ago |
| Edit | Post #286212 | Initial revision | — | about 2 years ago |
| Answer | — |
A: Level shifting of a 3 state logic pin No, a resistor divider is not appropriate, at least not if you want to get all the information from the STAT pin. In addition, that chart in the datasheet is incomplete at best, or downright misleading if you're less charitable. The first problem is that a single signal indicates three possible v... (more) |
— | about 2 years ago |
| Comment | Post #286181 |
It would also add an offset error. (more) |
— | about 2 years ago |
| Edit | Post #286181 | Initial revision | — | about 2 years ago |
| Answer | — |
A: When do I need to put anti-aliasing filter in front of SAR ADC? Since your noise has "unknown characteristics", you should do low pass filtering in analog before the discrete sampling of the A/D. The two parameters that matter are the frequency content of the signal, and the sampling rate. In theory, nothing is lost as long as the sample rate is more than twi... (more) |
— | about 2 years ago |
| Edit | Post #286157 |
Post edited: |
— | about 2 years ago |
| Edit | Post #286157 |
Post edited: |
— | about 2 years ago |
| Edit | Post #286157 | Initial revision | — | about 2 years ago |
| Answer | — |
A: Misuse of mod privilege? It seems your main question is why all the comments to your question about reactance were deleted. I deleted them because they were no longer relevant. They pointed out problems with the question, and explained why it was closed. You then fixed the question, it was reopened, and it has now gotten ... (more) |
— | about 2 years ago |
| Edit | Post #286134 | Initial revision | — | about 2 years ago |
| Answer | — |
A: Oscilloscope potentially ESD striked If you're really sure the symptom appeared right after the static discharge, then something in the front end of the amplifier may have gotten damaged. However, that sounds rather far fetched. Scopes should have protection against these kind of events. Were all the effected channels connected to so... (more) |
— | about 2 years ago |
| Edit | Post #286112 |
Post edited: |
— | about 2 years ago |
| Edit | Post #286112 |
Post edited: |
— | about 2 years ago |
| Edit | Post #286112 | Initial revision | — | about 2 years ago |
| Answer | — |
A: Duty cycle of buck-boost converter Nevermind (for now) what Wikipedia or anyone else says. Stop and actually think about it. One problem with the question is that is says "buck-boost" but doesn't otherwise define that. A buck-boost converter generally means that the output can be both above or below the input. There are differen... (more) |
— | about 2 years ago |
| Edit | Post #286104 |
Post edited: |
— | about 2 years ago |
| Edit | Post #286104 | Initial revision | — | about 2 years ago |
| Answer | — |
A: DAC controlled high side current source. It appears you want a positive current source with the following specs: 0 to 28 V compliance range. Up to 100 mA, adjustable via 10 bit or more digital value. 36 V supply is available. The dissipation from a linear pass element is OK. The large headroom at the high end allows for e... (more) |
— | about 2 years ago |
| Comment | Post #286103 |
How accurate must the output current be? If this is driven from a 16 bit D/A, it's a very different problem than if ±2% is good enough.
You need complete specs before even starting a design. There are various topologies, each with different things they are good at. You are getting way ah... (more) |
— | about 2 years ago |
| Comment | Post #286103 |
What's the complete compliance range your current source needs to have. You said the upper end is 36 V, but how close to 0 V must it still work? Also, what supply voltages are available, and don't tell me 36 V is the max. There will always be <i>some</i> drop across the current sense and/or pass e... (more) |
— | about 2 years ago |
| Comment | Post #286090 |
By starting out lecturing, you make it difficult to answer any question. Answerers then have to either spend effort dispelling false assertions, or answer but have others think they agree with the false assertions. If you have a question, ask it. Don't try to tell us what "we" do. (more) |
— | about 2 years ago |
| Edit | Post #286049 | Question closed | — | about 2 years ago |
| Edit | Post #286032 |
Post edited: Always be clear about something being homework, when it is. |
— | about 2 years ago |
| Edit | Post #286033 |
Post edited: |
— | about 2 years ago |
| Edit | Post #286033 | Initial revision | — | about 2 years ago |
| Answer | — |
A: Case temperature of MOSFET Yes, you seem to understand the concept. From the case to the ambient air, there will be 1.3°C per watt across the pad, and another 2.0°C per watt across the heatsink. In total, there will be 3.3°C per watt from case to ambient air. Since the part is dissipating 10 W, the case will b... (more) |
— | about 2 years ago |
| Edit | Post #286030 | Question closed | — | about 2 years ago |
| Comment | Post #286030 |
Important information to a question must be in the question itself. That also allows distilling down to the relevant information. I did try to look at your "a" link, but that was a whole web page with lots of babble and multiple diagrams. Put at least one example from each of your groups here in t... (more) |
— | about 2 years ago |
| Edit | Post #286021 |
Post edited: |
— | about 2 years ago |
| Edit | Post #286021 | Initial revision | — | about 2 years ago |
| Answer | — |
A: How to choose the right value for input voltage ripple of an SMPS? There are two issues with input voltage ripple: The input voltage being too high or low for correct operation, and high frequency noise on the input. The first is pretty straight forward. You make sure that the nominal voltage ± the peak ripple is never above or below the guaranteed operat... (more) |
— | about 2 years ago |
| Edit | Post #286014 | Initial revision | — | about 2 years ago |
| Answer | — |
A: PCB ground planes with isolated voltage Your description is confusing due to lots of hand waving, so it is hard to be specific. However, an isolated section should be separated from the non-isolated parts laterally. It depends on the exact spec or certification you are going after, but usually 5 mm is good. It can be more than that, lik... (more) |
— | about 2 years ago |
| Edit | Post #285991 | Initial revision | — | about 2 years ago |
| Answer | — |
A: Press fit PCB receptacle for plated holes (Marked for non-plated holes) Considering that the same manufacturer has models specifically for plated holes too, it probably matters. One thing that I noticed in looking around is that the models for unplated holes have a knurled collar, whereas the ones for plated were hexagonal there. My guess is that the knurling is me... (more) |
— | about 2 years ago |
| Edit | Post #285815 |
Post edited: |
— | about 2 years ago |
| Comment | Post #285921 |
This answer could be better, but it's written well enough, not wrong, and does supply some useful information. I wouldn't have normally upvoted it, but it doesn't deserve to be labeled a net negative. (more) |
— | about 2 years ago |
| Edit | Post #285930 | Initial revision | — | about 2 years ago |
| Answer | — |
A: Why are there more N type than P type MOSFETs? There are two predominant reasons you see N channel FETs more than P channel: N channel is the natural polarity for ground-referenced switches controlling loads with positive voltages. This is convenient because most controlling circuitry is ground-referenced too, with positive supply. With th... (more) |
— | about 2 years ago |
| Comment | Post #285854 |
Don't just tell me you're up for it. Help build a consensus at https://electrical.codidact.com/posts/285889 (more) |
— | about 2 years ago |
| Comment | Post #285854 |
The setting has been changed so that new users don't automatically get the Participate Everywhere privilege. That means they can't downvote until they get a few positive votes themselves. (more) |
— | about 2 years ago |
| Comment | Post #285854 |
We are discussing making downvotes public. If you want to see reform, it would be helpful if you weighed in. (more) |
— | about 2 years ago |
| Comment | Post #285913 |
Stalker can harass you on SE *because* of the hidden voting, not despite it. (more) |
— | about 2 years ago |
| Comment | Post #285913 |
These are the same arguments we here all the time, about what some people think <i>might</i> happen. There is no evidence. I think you're wrong. We won't know until it is actually tried. Until then we'll continue to have this <i>no it won't, yes it will</i> pissing contest. (more) |
— | about 2 years ago |
| Comment | Post #285907 |
@#53042 I really don't think it will get to that in the vast majority of times. Any system will have its problems. Don't forget that the current system has substantial problems this is trying to solve. It's easy to get caught up in the potential downside, but forget the very real downside of the s... (more) |
— | about 2 years ago |
| Comment | Post #285907 |
Vandals and retribution voters tend to hit only high-profile users, especially those that explain what they think is wrong with others' posts. In other words, responsible users will publicly explain problems, but then be targeted by anonymous retribution. That makes it less likely people will expre... (more) |
— | about 2 years ago |