Activity for Olin Lathrop
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Edit | Post #278341 |
Post edited: Removed pointless fluff. |
— | about 4 years ago |
| Comment | Post #278354 |
The circuit you show has nothing to do with any "bootstrap" technique. Its a R-C low pass filter followed by a unity gain buffer. The rolloff frequency is 1/2πRC, which is 1.6 Hz for the 1 MΩ and 100 nF part values you cite. (more) |
— | about 4 years ago |
| Edit | Post #278346 |
Post edited: |
— | about 4 years ago |
| Edit | Post #278347 | Initial revision | — | about 4 years ago |
| Answer | — |
A: Is ESD overhyped? Yes, damage due to ESD (electro-static discharge) is real. Just because you haven't seen it isn't much evidence of anything. Some obvious possibilities why you haven't observed the problem are: You failed to create a proper ESD event. You didn't measure the results properly. The built-in E... (more) |
— | about 4 years ago |
| Edit | Post #278346 | Initial revision | — | about 4 years ago |
| Answer | — |
A: Purpose of emitter resistor in a common collector amplifier First, let's nail down what circuit you are asking about. Your description is somewhat vague, so I picked this interpretation: Image Q2 is the emitter follower stage, driven by the previous common emitter stage of Q1. Your question seems to be why R2 exists. Some load is needed at DC to pu... (more) |
— | about 4 years ago |
| Comment | Post #277844 |
@Andy: Basically, using a PNP transistor around an LDO to detect input voltage high/low has been useful a few times, and I haven't seen it mentioned anywhere else. I may have generalized the problem too much so that it's not clear what the cute trick is. I should probably modify the *The Problem* s... (more) |
— | about 4 years ago |
| Comment | Post #278192 |
You really need to step back and look at the whole problem, not the details of one imagined solution to the higher level problem. You are apparently trying to measure electric fields. Ask about that directly in a separate question. In particular, explain what fields you are trying to measure, thei... (more) |
— | about 4 years ago |
| Edit | Post #278213 | Initial revision | — | about 4 years ago |
| Answer | — |
A: How to define Vsat for MOSFET as a switch? First, that's an archaic chip that requires a lot of circuitry around it to do anything useful. Why use this particular chip? Second, the datasheet gives you an example of how to use this part as a step-up converter with external switch. Why not follow that? Third, blindly following equations... (more) |
— | about 4 years ago |
| Edit | Post #278193 |
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— | about 4 years ago |
| Edit | Post #278193 |
Post edited: |
— | about 4 years ago |
| Edit | Post #278193 | Initial revision | — | about 4 years ago |
| Answer | — |
A: High pass filter design You are asking for a filter that passes 2% at 60 Hz and 99% at 90 Hz. That comes out to a transition of 97% of the amplitude within 0.6 of an octave, which is quite aggressive. The real answer My first reaction is that this smells like attempting to fix bad system-level design in the wrong pla... (more) |
— | about 4 years ago |
| Comment | Post #278161 |
@Lundin: Yes, I've been meaning to write up something about schematic drawing. I was originally going to add more to the SE post on that, but the mods turned it into community wiki and I lost control over it, so I gave up. (more) |
— | about 4 years ago |
| Comment | Post #278161 |
@Lundin: BOM optimizations are tricky because they can easily devolve to prices and vendors. That's probably why the question on SE was closed. I think our rules here are about the same as on SE. Maybe they just closed it quickly, or maybe it really did cross the line into prices and vendors. I s... (more) |
— | about 4 years ago |
| Edit | Post #278161 | Post undeleted | — | about 4 years ago |
| Edit | Post #278161 | Post deleted | — | about 4 years ago |
| Edit | Post #278161 | Initial revision | — | about 4 years ago |
| Answer | — |
A: Are BOM cost optimization questions on-topic? Yes, some BOM optimization questions like you mentioned could be on topic. This would include the general techniques for optimizing BOM costs. Getting into specific prices and vendors would be off topic. (more) |
— | about 4 years ago |
| Edit | Post #278152 |
Post edited: |
— | about 4 years ago |
| Edit | Post #278152 | Initial revision | — | about 4 years ago |
| Answer | — |
A: Design considerations when using a wireless charging battery pack There are various criteria that govern how well power is taken from a nearby changing magnetic field: Distance. The magnetic field diminishes rapidly with distance from the source. Shielding. Pickup ability. To get current from a changing magnetic field, there has to be a conducting loop w... (more) |
— | about 4 years ago |
| Edit | Post #278079 | Initial revision | — | about 4 years ago |
| Answer | — |
A: What is the significance of push-pull and open drain controls in circuits? A "normal" digital output actively drives both high and low. Open drain or open collector outputs only actively drive low, and go to high impedance when the signal is meant to be high. Some reasons the latter can be useful: Multiple outputs may be driving a bus. When devices only drive the bus ... (more) |
— | about 4 years ago |
| Edit | Post #278066 |
Post edited: |
— | about 4 years ago |
| Comment | Post #278066 |
@coq: I'm only looking at the circuit you posted as-is. I don't know what context or description might have come with it in any particular book, and that isn't relevant here anyway since you didn't specifically ask about that. Perhaps there is a flaw in my logic. If so, please point it out. (more) |
— | about 4 years ago |
| Edit | Post #278066 | Initial revision | — | about 4 years ago |
| Answer | — |
A: Design rules for opamp bootstrapping That circuit doesn't do what you think it does. Here is the circuit in question: Image The impedance seen at IN is definitely higher at high frequencies, but that is only due to it being artificially low at DC. At DC, there is a load of 2R on IN, in parallel with the opamp input impedance. ... (more) |
— | about 4 years ago |
| Edit | Post #278058 |
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— | about 4 years ago |
| Edit | Post #278058 |
Post edited: |
— | about 4 years ago |
| Edit | Post #278058 | Initial revision | — | about 4 years ago |
| Answer | — |
A: Is there a mathematical process resembling the terms "digital"/"discrete" and "analog"/"continuous"? I always had trouble understanding the terms "digital" and "analog" A digital signal is intended to indicate one of a finite set of discrete states. The number of discrete states is usually two for implementation simplicity. A two-valued digital signal is either high or low, on or off, etc. T... (more) |
— | about 4 years ago |
| Edit | Post #278001 | Initial revision | — | about 4 years ago |
| Answer | — |
A: Antenna Feed Line Question Any deviation from the example antenna could have significant and unintuitive consequences. Unless you have good antenna modeling software and good understanding of antenna physics (which you apparently don't since you're asking here), don't deviate from the suggested design. This includes the exac... (more) |
— | about 4 years ago |
| Edit | Post #277964 |
Post edited: |
— | about 4 years ago |
| Edit | Post #277964 | Initial revision | — | about 4 years ago |
| Answer | — |
A: MAX809's Irregularity Depending on Load Before we get into your problem, there are a few things to say about your descriptions. You need to step back and think about what we know and don't know, then learn to communicate specifications properly. That includes always making it clear what a number refers to, and using consistent names. ... (more) |
— | about 4 years ago |
| Comment | Post #277952 |
Too much unclear hand waving. Show a schematic. It is particularly confusing what all this buck converter is connected to, and how it relates to the MOSFET. (more) |
— | about 4 years ago |
| Comment | Post #277912 |
Seems reasonable, +1. (more) |
— | about 4 years ago |
| Edit | Post #277927 | Initial revision | — | about 4 years ago |
| Answer | — |
A: Doubt regarding loading. A voltage source is "heavily loaded" when something is drawing a large amount of current from it. "Large" in this context is relative to what the voltage source can deliver, or perhaps relative to some normal or typical operation within a system. For example, it might be reasonable to say a 12 V ... (more) |
— | about 4 years ago |
| Comment | Post #277550 |
@aditya: C37 is not relevant to the question, and details about it would only distract and add confusion here. Ask a separate question if you want to get into that. (more) |
— | about 4 years ago |
| Edit | Post #277845 | Question closed | — | about 4 years ago |
| Comment | Post #277845 |
*"on the output of a SMPS I recently bought because it was too high for the circuit I'm making"* What does it mean for an SMPS to be "too high"? Do you mean it's output voltage? Are you trying to lower the voltage with a filter? At first I thought you were trying to filter out ripple, but on clos... (more) |
— | about 4 years ago |
| Comment | Post #277845 |
Worked better than what? Show the other circuits, then it should be easy to explain why this one filters the ripple better. Also, tell us the ripple frequency you are trying to filter out. (more) |
— | about 4 years ago |
| Edit | Post #277845 |
Post edited: Delete time wating fluff. |
— | about 4 years ago |
| Edit | Post #277846 |
Post edited: |
— | about 4 years ago |
| Edit | Post #277853 | Initial revision | — | about 4 years ago |