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Can I use a different diode?

Unless you understand why the diode failed in the first place, or post a real circuit diagram, I'd give it a go if I didn't need the TV to actually work when you're done, and consider it a lovely ...
Scott Seidman's user avatar
1 vote

Can diodes be tested successfully in situ?

Maybe. Let's assume any capacitor is discharged fully, otherwise you can get odd effects such as negative resistance readings or smoke emissions from the DMM. Let's also assume that you know it's ...
Spehro Pefhany's user avatar
0 votes

How to determine in a nonlinear circuit with multiple diodes which diode is ON vs which one is OFF? Does it depend on the orientation of circuit?

Is it worth looking for the meaning of circuits? There are two ways to analyze circuits, each with advantages and disadvantages: One is to analyze circuits formally without caring about what it is, ...
Circuit fantasist's user avatar
1 vote
Accepted

Selecting a diode to prevent backfeeding from 5 V to USB-C port

The 5V rail is only feeding the 3.3V regulator that has a low dropout of about 1V, and the neopixels which work down to 3.7V. Any silicon diode rated for 1000mA minimum will do the job. A 1N4001 (SMD ...
Kuba hasn't forgotten Monica's user avatar
2 votes
Accepted

Identifying MOSFET (P9DVA) and diode (AD6) Markings

The MOSFET is a Si2318CDS from Vishay Siliconix (P9 is the significant code here). picture from LCSC: The diode is a NSR0340HT1G from ONSEMI. (AD is the significant code here, the last character ...
vivier's user avatar
  • 518
0 votes

How to make an integrated circuit diode?

You have four-terminal MOSFETs, right? Use the body diode explicitly: Did you catch it? -- the diode is already shown! That's what the arrow means, it's the substrate-channel junction. There's ...
Tim Williams's user avatar
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1 vote

How to determine in a nonlinear circuit with multiple diodes which diode is ON vs which one is OFF? Does it depend on the orientation of circuit?

In 4.3(a) start by asking if the \$-3\:\text{V}\$ is more negative than either or both of the sources at the diode anodes. The answer is yes in this case. So you know that at least one of the two ...
periblepsis's user avatar
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0 votes

How to determine in a nonlinear circuit with multiple diodes which diode is ON vs which one is OFF? Does it depend on the orientation of circuit?

My approach is as follows. In part (a), both diode cathodes have the same potential, \$V\$. The diode which is most forward biased will be the one whose anode has the higher potential. That's D2. In ...
Simon Fitch's user avatar
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4 votes

How to determine in a nonlinear circuit with multiple diodes which diode is ON vs which one is OFF? Does it depend on the orientation of circuit?

This kind of problem is solved by a guess-and-check method. Say in part (a) you guessed that both diodes are forward biased. Then you'd find that node "V" must be at +1 V (assuming a very ...
The Photon's user avatar
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5 votes
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Issue with solenoid valve sparks despite using two 1N4001 flyback diodes

The photograph and the pictorial do not tally. The photograph shows the flyback diode wrongly wired across the power supply terminals. The corresponding schematic is as follows. On the other hand the ...
vu2nan's user avatar
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6 votes

Issue with solenoid valve sparks despite using two 1N4001 flyback diodes

simulate this circuit – Schematic created using CircuitLab The diode should be connected across the solenoid, not the power supply. In the photo supplied you seem to be touching the solenoid ...
Transistor's user avatar
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0 votes

Issue with solenoid valve sparks despite using two 1N4001 flyback diodes

It will spark if you disconnect the valve from the diode with the wire like that, because 2A needs to flow somewhere to discharge the stored magnetic field, and the voltage will jump to very high ...
Justme's user avatar
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0 votes

Are these germanium diodes?

The parts are likely to be fuses due to the 00.0 ohm. Also - the case is transparent as this will allow a visual indication if it is fused or not.
helarsen's user avatar
4 votes
Accepted

Are these germanium diodes?

If they are diodes, they will have a voltage drop in one direction across them. Put the meter in diode mode and measure (both ways) again. If you see a voltage while in diode mode in one direction, ...
Voltage Spike's user avatar
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0 votes

Why are there diodes going to D+ on this alternator/generator?

The D+ (three diode) supplies a voltage to energize the field coil (rotor) that supplies DF. If the voltage reaches 13.7 to 14.3 V (no more than 15 V), the transistor, MOSFET, or IGBT will turn off ...
Glenn Dumlao Doringuez's user avatar
0 votes

Why is collector current in a diode-connected transistor not subject to the non-ideality of the B-E junction that it must necessarily traverse?

Doty is partly right (mechanism #2). To understand the behavior of collector and base currents the detailed mechanisms of carrier transport need to be understood. It's not possible to explain in a ...
Fred's user avatar
  • 166
0 votes

Why is collector current in a diode-connected transistor not subject to the non-ideality of the B-E junction that it must necessarily traverse?

I believe there are two things going on. The parasitic base resistance is usually much higher that the parasitic collector and emitter resistances, so passing most of the current between collector ...
John Doty's user avatar
  • 3,569
0 votes

Why is collector current in a diode-connected transistor not subject to the non-ideality of the B-E junction that it must necessarily traverse?

This question made me think again about the philosophy of this active diode arrangement and for the umpteenth time try to make sense of it. Now I have the feeling that I finally succeeded... Basic ...
Circuit fantasist's user avatar
0 votes

Unpredicted voltage drop at the output of a Graetz bridge

The simulator's DC voltmeter doesn't appear to handle unsmoothed DC properly. Try adding a 1 μF capacitor after the rectifier.
Transistor's user avatar
  • 175k
5 votes

Logarithm circuit using op-amp not working

When the circuit does not work There is a paradox in circuitry that perhaps applies to everything in life - for the purposes of understanding, it is better that the circuit does not start working ...
Circuit fantasist's user avatar
3 votes

Logarithm circuit using op-amp not working

Here is a simulation with microcap v12 of this circuit with temperature variable (T°=0, 27, 50 °C). Correction of "offset" applied, opamp is an LF13741, +/- 15 V power supplied.
Antonio51's user avatar
  • 12.7k
5 votes

Logarithm circuit using op-amp not working

I did try that and it gave me a very accurate result for ln2 but it gave me a negative value for ln5. I used BC547. When sizing the resistor and diode (diode connected transistor) it is important to ...
Math Keeps Me Busy's user avatar
6 votes
Accepted

Logarithm circuit using op-amp not working

There can be quite a lot of variation in diode ideality, even in diodes from the same batch, so even if you did have an accurate figure for one particular device, it will not necessarily be the same ...
Simon Fitch's user avatar
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0 votes

How to check if a solar panel has a built-in blocking diode?

If the panel is in the dark and you force its voltage to its nominal open circuit voltage, it should draw something like its nominal short circuit current if there is no blocking diode. If there is a ...
John Doty's user avatar
  • 3,569
1 vote
Accepted

Reverse voltage parameter Vr in constant current regulators

Yes, you likely would violate the reverse voltage spec in that situation. Although "maximum reverse voltage between all terminals" (from the datasheet) isn't the most technical description ...
BeB00's user avatar
  • 5,410
0 votes

Why is diffusion current due to p side in a diode inversely proportional to doping concentration of p side in the case of forward bias?

In a forward-biased p-n junction diode, the diffusion current on the p-side is primarily due to the movement of heavily doped holes towards the lightly doped n-side. The higher doping concentration in ...
fergerg's user avatar
  • 11
0 votes
Accepted

Will the PCB from the project found online work the same as the one from the video?

I've ordered the OSHWLab project PCB and did the same thing as on the video. It works.
Scouteeer's user avatar
1 vote

Understanding complex circuits

The question you're asking can be interpreted as, "how can I model circuits that contain non-linear elements"? The answer is, you step up into the domain of circuit simulation, using a tool ...
hacktastical's user avatar
  • 52.7k
0 votes

Understanding complex circuits

Understanding diode circuits by intuition Begin with trying to find out what the purpose of the circuit is (switches signals, stabilizes voltage, etc.) to understand what function the diodes perform ...
Circuit fantasist's user avatar
2 votes

Op-amp with Schottky diode

Building Schmitt trigger Here is a possible scenario for building the circuit in four steps that might help make sense of it. 1.Producing V- and V+ First we connect the two input stage sources through ...
Circuit fantasist's user avatar
0 votes

Understanding complex circuits

In general, discrete and simple (one transistor or diode) non-linear devices aren't identical to each other, so they vary one to another, and vary their behavior with operating temperature, too. They ...
periblepsis's user avatar
  • 7,570
3 votes

Op-amp with Schottky diode

... the voltage is difference between the two inputs is constant e.g. 0.4 V, independent of the input voltages, ... Diodes are 1N4148. This is not true. Here are two examples of simulating with opamp....
Antonio51's user avatar
  • 12.7k
6 votes

Op-amp with Schottky diode

The diodes conduct hardly at all near the switching point, which is where the two input voltages are almost equal (within a mV or so for most op-amps), so they can be ignored when analyzing the ...
Spehro Pefhany's user avatar
4 votes

Op-amp with Schottky diode

My idea of this circuit is that the voltage is difference between the two inputs is constant e.g. 0.4 V, independent of the input voltages, so how can the op-amp operate? Your understanding is flawed....
Andy aka's user avatar
  • 451k
1 vote

Determine polarity of IrED with multimeter

I experienced the same, new and surprising to me, phenomena today. In contrast to the other answer I would bet the polarity is pin 1 = anode. That is, the larger voltage drop is the forward bias. Here'...
Heath Raftery's user avatar
3 votes
Accepted

Difference (if any) between SMAJ58A and SMAJ58A-13-F

Diodes uses these numbers/letters to designate product packing: https://www.diodes.com/design/support/frequently-asked-questions/#faq-679 When suffixes are appended to part numbers, what do they ...
Tim Williams's user avatar
  • 31.8k
0 votes

Difference (if any) between SMAJ58A and SMAJ58A-13-F

They link to the same datasheet, they are the same. Use whatever suffix your distributor (the place you want it purchased from) uses.
Voltage Spike's user avatar
  • 81.1k
0 votes

Best choice between flyback diode or an RC snubber

voltage creates the arc circuit, current through the circuit burns away the metal, both energy factors are present when erosion occurs. a typical sized RC will possibly absorb much less energy than a ...
camg's user avatar
  • 1
0 votes

Will the PCB from the project found online work the same as the one from the video?

In both cases you will have to solder the cube from wires and LEDs. Neither project has a PCB to put all of the LEDs on. The OSHWLab project doesn't include the software or any description - using it ...
JRE's user avatar
  • 70.7k
1 vote
Accepted

Why is the bottom half of the circuit shortcircuited?

For charge to flow there must be a closed path around the voltage source V1. If V1 is negative D1 is reversed biased so can be removed for the sake of analysis. So the circuit can be redrawn as in ...
RussellH's user avatar
  • 14.5k
2 votes
Accepted

Understanding a short solution to a diode exercise

I also offer a redraw. :-) As we are in the -24V case, I placed GND on top. I hope that helps. Why is the bottom half (everything below the source, apparentely) shortcircuited? The "components ...
Carsten's user avatar
  • 96
1 vote

Why is the bottom half of the circuit shortcircuited?

For this post I'm only concerned in the case V1 = −24V With V1's upper terminal at -24 volts, the only route for current to flow is through R1. No other current will flow. the bottom half of the ...
Andy aka's user avatar
  • 451k

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