Posts by Olin Lathrop
To summarize, it seems you want a circuit that will detect an input voltage high/low with a threshold somewhere between 0 and 3.3 V, must operate correctly with 0-3.3 V input, but must tolerate inp...
I guess it would work. I have used electrodes on a PCB to detect whether water level got high enough to turn on a sump pump. It worked, although it hasn't been installed very long. In that case ...
Is there a scientific way to estimate the resistance of a pogo pin? Ultimately there must be, but it generally requires knowing things you don't know. Worrying about the resistance of the barrel ...
When should a transformer core be potted? Whenever you need some of Mechanical ruggedness. High dielectric strength. Minimize vibrations (and therefore audible whine) from capacitive, inductive...
Yes, votes on meta should not factor into rep. Meta downvotes indicate disagreement, not that you're a terrible person, have the IQ of a garden slug, and cast dispersions on your heritage like the...
Starting with your first circuit: It seems a little klunky, but should work. I don't like the D1 and D2 diodes. The reason I placed D1 is to avoid triggering the mosfet with very low voltage li...
One of the first things you should do is provide a connection for the scope probe ground. If you think you'll be regularly looking at signals on this board, then one of those little loops or pins ...
I have also designed and ordered a PCB It seems rather pointless to ask after you've already ordered the board. only uses THT-components That's just plain silly. This is the kind of thing that ...
calculate the voltage that will center the magnetic field of a coil This is not possible since the voltage has no effect on the position or shape of the magnetic field. The position and shape are...
In general, the on/off delay is how long it takes from changing the input until the output starts to do something. The rise/fall time is how long it takes to do the something, once it starts doing...
Rise and falls times are limited by the maximum slew rate the opamp can produce. This is something you look up in the datasheet. Note that the slew rate might be dependent on supply voltage and p...
EMPs (electro-magnetic pulses) occur naturally often. Every lightning strike is one example. Larger EMPs have been created artificially with nuclear weapons. The Starfish Prime H-bomb test cause...
My control system gets a signal representing the plant output, but that signal has a lot of noise on it. The control system goes nuts trying to react to the noise. I need to filter out the noise ...
Your circuit It doesn't make sense that the yellow blob is a current sink: If it were a current sink, then there would be no point to the resistor in series with it. That only wastes power, re...
First Circuit Let's start by looking at the conventional current mirror circuit: The base of Q1 (Not sure which one that is? Use component designators next time!) is driven to whatever it takes...
Catching a flyback pulse is actually a rather easy application for a diode. Many of the diode parameters don't matter much. The basics are: Reverse voltage. This is simply the maximum voltage t...
The Codidact team has recently informed us that it is now possible to have different rep bumps on different post types. See this new answer by Monica to the old meta discussion that created the Pa...
I have boycotted the SE and neither asked or answered any questions so am happy to have a new home here. I'm glad you're here. You might also want to mention this in your SE profile, and point pe...
FET source-followers are generally less predictable than BJT (bipolar junction transistor, like NPN or PNP) emitter-followers. An emitter follower output is one diode drop below the input. The vo...
Roughly around 27 MHz is the old "CB" (Citizen's Band, 11 meter) frequency block. The advantage of this band is that it is free to use with limited power. This is the band "walkie talkies" used t...
1 - Signal 2 - GND 3 - PWR 4 - Signal This seems to be common advice, especially on the 'net someplace, but that doesn't make it good. Stop and actually think about what problem you are trying to s...
First, let's be clear about something. All currents partially take all paths relative to the inverse of the path impedances. It's not an all or nothing function. This "Takes the path of least re...
You generally want complementary NPN/PNP pairs when they are used as opposites of each other in the same circuit. One transistor is usually used with opposite polarity as a mirror image of the oth...
The short phrase is trying to capture the two broad classes of topics here: Electronic things, like opamps, transistors, microcontrollers, 20 W power supplies, and the like. Utility-scale power sys...