Activity for Olin Lathrop
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Edit | Post #293361 |
Post edited: |
— | 4 months ago |
| Edit | Post #293380 | Initial revision | — | 4 months ago |
| Answer | — |
A: Does My Circuit Contain High-Speed Signals? No, none of your signals sound like "high speed". However, that doesn't mean you should ignore high frequency noise issues. If you can dedicate one layer to be mostly a ground plane, that would be good. If this is a high volume product optimized for low cost, then you get creative with only two ... (more) |
— | 4 months ago |
| Edit | Post #293375 |
Post edited: Enough with the annoying fluff! This is now the second time I had to edit it out. Read the rules already! |
— | 4 months ago |
| Edit | Post #293379 | Initial revision | — | 4 months ago |
| Answer | — |
A: Thick trace or a Polygon? Not much. If the wide power trace is good enough to handle the current, then it's, well, good enough. If you really don't have anything else to do with the copper space, then you might as well make the power trace wider, but there is a usefulness limit. (more) |
— | 4 months ago |
| Edit | Post #293359 |
Post edited: Removed content-free fluff. |
— | 4 months ago |
| Edit | Post #293361 | Initial revision | — | 4 months ago |
| Answer | — |
A: Thermal Relief – Yes or No? The main point is that you need thermal symmetry between the two pads of a small package. You want the solder paste to melt at the same time between the two pads. Molten solder has significantly higher surface tension than solder paste. When the solder melts, the surface tension will try to "lev... (more) |
— | 4 months ago |
| Edit | Post #293356 |
Post edited: |
— | 4 months ago |
| Edit | Post #293356 | Initial revision | — | 4 months ago |
| Answer | — |
A: Dual ratiometric power scaler design review and issues Partial answer awaiting more specs Your question can't really be answered until we know how accurate the resulting solenoid drive levels need to be relative to the 0-10 V input signals, and how fast the system must respond. However, here are a few observations in the mean time: Use a microcont... (more) |
— | 4 months ago |
| Comment | Post #293355 |
What accuracy? What frequency response? (more) |
— | 4 months ago |
| Edit | Post #293350 | Initial revision | — | 4 months ago |
| Answer | — |
A: Solder mask bridge issue Talk to your board house. 4 mil slop for the soldermask around pads is excessive. Leaving 4 mils is fine for larger parts, but as you say, it doesn't work for fine pitch. The main reason for making the soldermask hole larger than the pad is to allow some room for mis-registration between the cop... (more) |
— | 4 months ago |
| Comment | Post #293311 |
Your equations still have undefined terms, or at least poorly notated. This is now the second time I've looked and wasted my volunteer time. I probably won't bother with a third.
You might start with understanding the circuit first, and what you are trying to achieve with it overall. C2 doesn't... (more) |
— | 4 months ago |
| Edit | Post #293311 | Initial revision | — | 4 months ago |
| Answer | — |
A: Transfer function of arbitrary dc-dc converter I stopped trying to read your equations after the second undefined term. In general, start analyzing such things assuming switches, diodes, and the like are ideal. Also consider continuous and discontinuous as two completely separate cases. This will give you a good starting point to see what is... (more) |
— | 4 months ago |
| Edit | Post #293310 | Initial revision | — | 4 months ago |
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A: Differential current signal to single-ended voltage conversion The first thing I noticed is that all your circuits use separate resistors to convert the current of each side to a voltage. That will cause a differential mode error signal to the extent the resistors aren't equal. I would start with a single resistor for the current to flow thru to convert the ... (more) |
— | 4 months ago |
| Edit | Post #293274 |
Post edited: |
— | 5 months ago |
| Edit | Post #293274 | Initial revision | — | 5 months ago |
| Answer | — |
A: Single-supply non-inverting op-amp with an output offset. How to create the output offset? Your first circuit topology makes sense, although some of the part values are questionable. How the circuit works R37 provides the bias supply for the condenser microphone with a predictable impedance. C33 tries to reduce noise on the 3.3 V supply. The output of the microphone is AC-coupl... (more) |
— | 5 months ago |
| Comment | Post #293271 |
There are lots of things wrong. This should be discussed in main Meta. (more) |
— | 5 months ago |
| Edit | Post #293271 | Initial revision | — | 5 months ago |
| Answer | — |
A: Potential MathJax section in the formatting help Yes, we should add how to use MathJax to the help for this site. Unfortunately, there are several things that work against getting this done: The Codidact help system sucks! When we first started this site, I wrote a bunch of help pages, carefully designed to present information keeping both the... (more) |
— | 5 months ago |
| Edit | Post #293120 | Initial revision | — | 6 months ago |
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A: Is Feeding a Watchdog Timer from an ISR a Bad Practice? Feeding the watchdog from an interrupt service routine is indeed a bad idea, usually. It depends on what you are really trying to protect against. The purpose of a hardware watchdog is usually to allow recovery if the processor stops doing what it's supposed to be doing. The question then become... (more) |
— | 6 months ago |
| Edit | Post #293082 | Initial revision | — | 6 months ago |
| Answer | — |
A: Summing op-amp 10 meters long Yes, that should work. Each sensor is then dumping a current related to its measurement onto a single common wire. Basically, the sensor outputs are summed because currents add. 10 m shouldn't be an issue for 1 kHz. The harder problem is avoiding external noise pickup. Make sure everything is ... (more) |
— | 6 months ago |
| Comment | Post #279592 |
Unfortunately that is something the author needs to do. The links weren't to the image hosting part of Codidact, as they should have been. (more) |
— | 6 months ago |
| Edit | Post #276217 |
Post edited: |
— | 6 months ago |
| Edit | Post #293049 |
Post edited: |
— | 6 months ago |
| Edit | Post #293049 | Initial revision | — | 6 months ago |
| Answer | — |
A: Ground loss protection It all depends on what is connected between the main board and this "hat" board. Your schematic doesn't show any of these connections, so we can't really tell. In the end, the high current loop should be isolated from everything else. In your context, V3 would be an isolated supply. The circuit... (more) |
— | 6 months ago |
| Edit | Post #293044 | Initial revision | — | 6 months ago |
| Answer | — |
A: OP-AMP PT100 signal conditioner I'm going to guess that by "PT100" you mean a positive coefficient temperature sensor with a nominal resistance of 100 Ω at 0°C or 25°C. Whatever it is you mean, it should be in your question. This circuit has several independent parts, but that's hard to see at first glance due to ... (more) |
— | 6 months ago |
| Comment | Post #293038 |
Define "PT100" and how you want to "condition" its signal. (more) |
— | 6 months ago |
| Edit | Post #292999 |
Post edited: |
— | 6 months ago |
| Edit | Post #292999 | Initial revision | — | 6 months ago |
| Answer | — |
A: Controlling the shutdown pin of an IR Transceiver When the switch is ON the transceiver will be active No, it's the other way around. First, you should be able to see the bar over SHDN in the datasheet. That means negative logic, where low is asserted. Second, on page 5 of the datasheet the description for the SHDN pin is "Shutdown input. ... (more) |
— | 6 months ago |
| Edit | Post #292938 | Initial revision | — | 7 months ago |
| Answer | — |
A: Controlling the Low power mode of Buck Boost converter using a Microcontroller Read the datasheet and do the math. On page 3 of the datasheet we find that the guaranteed high and low threshold voltages for the PS/SYNC input are 1.4 and 0.4 V, and its maximum input current is 100 nA. First, let's analyze your circuit letting the input float high. Your lowest power input v... (more) |
— | 7 months ago |
| Edit | Post #292901 | Initial revision | — | 7 months ago |
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A: OPA2211 datasheet discrepancy You are right in that the gain at 80 MHz is clearly not 100. Both the initial marketing points and the graph seem to agree on a gain⋅bandwidth of 45 MHz. There does appear to be a slight kink in the gain curve at 800 kHz, but it looks like the gain is a bit below 100 there. A gain of 100 at... (more) |
— | 7 months ago |
| Edit | Post #292876 | Initial revision | — | 7 months ago |
| Answer | — |
A: How does JFET biasing work in a 2-terminal electret condenser microphone? The voltages from the raw microphone are quite small and fairly high impedance. That's why an amplifier at the mic is needed in the first place. The signal on the wire would be way too small compared to noise in normal environments. The FET is a simple amplifier that increases the voltage and decr... (more) |
— | 7 months ago |
| Edit | Post #292791 | Initial revision | — | 8 months ago |
| Answer | — |
A: Opto-coupler, slow turn off Some optos are really slow. What off time is yours specified for? Your circuit could be better. The transistor is turned on thru 1 kΩ, but off thru 11 kΩ. You are also giving it way more base current than needed, slowing turn-off. Move R318 to the other side of R317 and adjust bo... (more) |
— | 8 months ago |
| Comment | Post #285392 |
It looks like those images weren't hosted on Codidact as they should have been. The third-party host apparently deleted them, or changed the URL. This is exactly why images shown here should be hosted here. (more) |
— | 8 months ago |