Activity for Olin Lathropâ€
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Edit | Post #292938 | Initial revision | — | 13 days 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) |
— | 13 days ago |
| Edit | Post #292901 | Initial revision | — | 24 days ago |
| Answer | — |
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) |
— | 24 days ago |
| Edit | Post #292876 | Initial revision | — | 27 days 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) |
— | 27 days ago |
| Edit | Post #292791 | Initial revision | — | about 1 month ago |
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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) |
— | about 1 month 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) |
— | about 2 months ago |
| Edit | Post #292691 | Initial revision | — | about 2 months ago |
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A: Why did the battery blow out? Those batteries must be for powering electronics that receives commands from your controller or remote. They don't have anywhere near the energy to raise something like the headrest of a normal bed. However, that has nothing to do with why one of them failed. I've never seen a 9 V battery fail l... (more) |
— | about 2 months ago |
| Edit | Post #292690 | Initial revision | — | about 2 months ago |
| Answer | — |
A: Which transistor type to use for charge shuttle, as part of an active charging circuit? You need something with very low on-state voltage drop. That effectively means some type of FET. Those look resistive when on, as opposed to a voltage source like a BJT does. You need to look carefully at the voltages when the switches are supposed to be off. The body diode of MOSFETs and the g... (more) |
— | about 2 months ago |
| Comment | Post #292541 |
The sine will be infinite in time, not voltage. I have edited the answer to make that clear.
Also, a 1 V step input will result in less than 2 Vpp sine due to the two inductors acting like a divider. (more) |
— | about 2 months ago |
| Edit | Post #292541 |
Post edited: |
— | about 2 months ago |
| Edit | Post #292541 | Initial revision | — | 2 months ago |
| Answer | — |
A: Analysis of LC circuit using intuition A quick intuitive way of looking at this circuit is that the voltage source, L1, and L2 can be thought of as a lower voltage source with a single lower inductance in series. This is the same as finding the Thevenin equivalent if L1 and L2 were just resistors. Put another way, L1 and L2 are in paral... (more) |
— | 2 months ago |
| Edit | Post #292527 | Initial revision | — | 2 months ago |
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A: Connector rated voltage vs IPC-2221B and IEC 62368 If I use this connector at its rated working voltage, does that automatically mean I am not complying to IEC 62368 safety standard? The pattern you reference seems to assume one side of all eight signals are tied together. If that is really true, then I don't see how to interpret working voltage ... (more) |
— | 2 months ago |
| Edit | Post #292496 | Initial revision | — | 2 months ago |
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A: Issue in Cable Sizing and control cable selection 200 HP is 147.1 kW. At 480 V, it takes 306 A to transfer that much power. You didn't say, but your 480 V power feed is probably three-phase, and the motor is three-phase too. I don't remember how exactly that reduces the current requirements in each of the three conductors, so let's just say you... (more) |
— | 2 months ago |
| Comment | Post #292378 |
Explain in a few sentences what the software you are looking for is supposed to do. "PCB modeling" is too vague. Links rot over time, and go to unknown places. Information required to understand the question must be in the question itself. Links are OK only for supplemental information. (more) |
— | 3 months ago |
| Edit | Post #292309 | Initial revision | — | 3 months ago |
| Answer | — |
A: Do hobbyist slabtop Wi-Fi modifications need to consult FCC regulations? is it possible that moving around laptop antennas does not change the specifications drastically, because, for example, the antennas are low-power The radiated power is probably not low compared to what is allowed. Laptops with limited WiFi range don't sell well. The limit could also be in the... (more) |
— | 3 months ago |
| Comment | Post #292235 |
Clicking on that link goes to a page that pops up something about permissions. No thanks. Not going to look further. Please provide a proper link. (more) |
— | 3 months ago |
| Edit | Post #292148 | Initial revision | — | 4 months ago |
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A: Purpose of resistance between SENSE/FORCE line of power supply I see that Nick has already provided a good answer to R5, so I'll only address this: Furthermore, an amplifier symbol called "gm" is labeled as transconductor. What does it do? What you show is a rough diagram only intended to give enough insight into the internal workings to use the power supp... (more) |
— | 4 months ago |
| Edit | Post #292090 |
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— | 4 months ago |
| Edit | Post #292090 | Initial revision | — | 4 months ago |
| Answer | — |
A: Circuit for earth conductor presence detection The section you quoted says: "by injecting a small amount of current into the ground". With a solid ground connection, the voltage on their ground pin shouldn't change no matter what current is injected onto it. If they inject a current and see a resulting voltage change, then they know the groun... (more) |
— | 4 months ago |
| Edit | Post #292089 | Initial revision | — | 4 months ago |
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A: CAN bus open circuit detection There is no direct way to determine whether the PIC is connected to a CAN bus. Part of the problem is that the PIC never directly connected to the CAN bus anyway. There is a transceiver chip like the MCP2551 between the PIC and the bus. The PIC interfaces to the transceiver via two digital signals... (more) |
— | 4 months ago |
| Edit | Post #291984 | Initial revision | — | 4 months ago |
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A: How to operate a chip very close to its absolute maximum voltage? 3.6 V is not the absolute maximum voltage. The table you show explicitly says "Recommended Operating Conditions". Therefore, running the chip up to 3.6 V is perfectly fine. (more) |
— | 4 months ago |
| Edit | Post #291936 |
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— | 5 months ago |
| Edit | Post #291936 |
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— | 5 months ago |
| Comment | Post #291934 |
The title of your question doesn't match the content. The title talks about "very low currents", but this is not brought up in the question at all. (more) |
— | 5 months ago |
| Edit | Post #291936 | Initial revision | — | 5 months ago |
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A: Are LDOs more efficient than switching regulators in very low currents? Do the math. At 5 V in and 1.2 V out, a linear regulator is limited to (1.2 V)/(5.0 V) = 24% efficiency. At 3 V in, the limit is 40%. The actual efficiency will be little less due to the current that the regulator itself uses to operate, but compared to 150 mA that will be negligible with pretty... (more) |
— | 5 months ago |
| Edit | Post #291841 | Initial revision | — | 5 months ago |
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A: Using only ceramic capacitors on an input of an SMPS - unclear advice from manufacturer First, note this only applies when the line to the input power source is long enough to have significant inductance. If the power source is on the same circuit board, then this isn't an issue. They are modeling the input power feed like this: This is basically an L-C tank circuit with no w... (more) |
— | 5 months ago |
| Edit | Post #291741 |
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— | 5 months ago |
| Comment | Post #291745 |
I can replicate this, as you describe. (more) |
— | 5 months ago |
| Edit | Post #291741 | Initial revision | — | 5 months ago |
| Answer | — |
A: Missing voltage rating They don't outright tell you the maximum operating voltage, probably because that would imply a power level beyond what they think anyone would use this connector with. Note that it is intended for 50 Ω transmission lines. 100 VAC would imply 200 W. There are two clues in how they test the... (more) |
— | 5 months ago |
| Edit | Post #291716 |
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— | 5 months ago |
| Edit | Post #291716 |
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— | 5 months ago |
| Edit | Post #291716 | Initial revision | — | 5 months ago |
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A: STM32. What should be done in firmware for VBUS detection through a GPIO pin? What should the firmware do when it detects that VBUS (re)appeared? What should the firmware do when VBUS has disappeared? I'm not familiar with the STM32 USB library, and have only dealt with this on PICs using my own USB library. I'll therefore answer the generic case. The most important th... (more) |
— | 5 months ago |
| Edit | Post #291671 |
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— | 6 months ago |