Questions tagged [diodes]
Diodes are semiconductor components made from a P-type (or metal in Schottky diodes) and N-type material (usually silicon, but germanium, selenium, and gallium arsenide can also be used), that allow current to flow in one direction only.
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How to model this diode in spice?
How to model this BZX79C6V2 zener diode in spice(ltspice recommended )?
reference:-https://www.farnell.com/datasheets/2303921.pdf
These are the possible parameters
https://ltwiki.org/LTspiceHelp/...
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How to solve this question based on diodes?
How to find the average using integration?
My attempt
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Zener Clipper Circuit Load Issues [closed]
If a clipper circuit is being used for an incoming AC signal and the zener voltage is 15v and resistor is 39ohms(chose this to limit current seen on diode). Why is it that with no load hooked up the ...
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Characteristic of a Resistor/Diode Simple Circuit in LTSpice
Our teacher in class instructed us to experiment with a resistor/diode circuit in LTspice. The goal is to display the I-V characteristic of the resistor, as well as that of the diode, and test them ...
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Can someone explain this circuit to me in terms of what’s being asked? [closed]
I’m curious about the inner workings of this circuit in terms of the questions being asked. I want to develop an intuitive understanding of how it works. Thanks.
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CRS01(TE85L,Q,M) Schottky diode is open both ways
I was testing my PCB when I noticed that I get +12 V on USB Vbus line, even though I placed a Schottky diode to block it.
The idea is to use +12 V voltage source to provide power and to connect USB ...
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How to check if a solar panel has a built-in blocking diode?
Is it as simple as connecting a voltage to a fully shaded solar panel and checking if any current flows into it? For example using a battery with a resistor in series to limit the current. Or does the ...
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How does dB apply for non-linear components?
I understand that decibels are used to express power and we can use 20log(V1/V2) and 10log(P1/P2) to find the voltage and power ratios. But what are we meant to do when it comes to non-linear ...
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U16C60D - Dual Series Connection Rectifier
I can't find any replacement for the U16C60D rectifier. It is possible to put two seperate diodes (each at 8A/600V) in series like the "U16C60D" or inside the component it is not only just a ...
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Sequential diode and capacitor - low vs high capacitance
Here is my circuit:
Diode and capacitor
When I set capacitor to 1F I get the following voltage graph:
When I set capacitor to 1pF I get the following voltage graph:
Why do I get this totally ...
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What's the formula for an idealized diode?
How do I mathematically describe the curve of an idealized diode? I want to express the dependency of i and v in one expression. Is it possible?
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Can I use a Schottky Diode to prevent a voltage regulator from being used in reverse?
When I use a USB Serial Programmer, the 3.3V line from the programmer gets connected to the 3.3V line from the circuit below.
The problem is that I also get 3.3v on the voltage regulator's VIn, ...
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Diodes for implementing digital logic
This diagram in this post is from Microelectronic Circuits by Sedra and Smith. The question corresponding to this picture asks to write a truth table with A and B as inputs and X and Y as outputs and ...
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Understanding the working of the diode in opamps [closed]
I had seen one of the schematics where I found a diode in the feedback loop. The schematic is shown below, where I have two inputs from 0-5. I have the following questions about this:
What is the ...
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Shorted Input Protection
I try to understand that Shorted Input Protection diode. I didn't understand clearly from datasheet. How can I find suitable diode for this protection circuit. What is use for? If I have a 28V 10A ...
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Is m called the grading coefficient and equals to 1/2 or 1/3 in the following question?
The following is an example from Digital Integrated Circuit.
Consider the following silicon junction diode:
\$C_{j0}= 2 \times 10^{-3} F/m^2\$,
\$A_D = 0.5 {\mu m}^2\$, and \$ \phi_0 =0.64 V \$
A ...
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How does this circuit double the voltage? [closed]
Please explain image 2. I don't get working of this circuit.
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Minimum hfe requirements
Is this the minimum voltage and current value for the said dc current gain.
Thanks
https://alltransistors.com/adv/pdfdatasheet_motorola/bc546_bc547_bc548.pdf
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Why is a reverse-biased diode needed when connecting power supplies in series?
When reading application notes, I've came with the suggestion of adding reverse-based diodes across each of power supplies connected in series.
A diode in reverse bias must be added across output ...
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Zener diode for overvoltage protection and earthing
I am designing a small circuit where the goal is to measure the current. The CT measures the current, which passes through a shunt resistor. The ADC convert the signal so it can be further processed.
...
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Finding the diode ID and VD in a circuit
I was asked to find the ID and VD in this circuit. The Vknee = 0.7V , Vin = 5 V and R = 1000 ohms.
I just wanted to make sure I'm understanding how to solve this correctly, so what I've done is:
Vin =...
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What is this component? Marked XF 1A
Help me identify the component on the board labeled XF 1A M with the designation VD13 on the board.
It's a diode, but which one (TVS, Shottky or another)?
Mounted in series in the +5V relay power line....
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Reverse protection Diode selection
I want to add Schottky diode to implement reverse protection like the image.
And I will use B350. (Internal Fet's body diode Vf is 0.3V, so B350 seems suitable)
But I concern If I miss any kind of ...
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Unidirectional or Bi-directional TVS diodes - Which one to use?
I would like to understand in which places one should be using a unidirectional TVS diode and a bi-directional TVS diode.
In the USB power line, VBUS (5V), is it enough to place an unidirectional TVS ...
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Repairing Garage Door Control Board
Update summary:
I recapped the whole board :D - It works perfectly!
Re the main/bigger cap, my local electrics shop didn't have a 330uF 35V so I went for a 470uF 35V instead.
Just for my own learning, ...
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RC + DIode Problem
Consider every component to be ideal.
V_in is a square pulse with dc level 0 and amplitude = 10 (Basically square pulse at +-5V)
Find v_out vs time (draw the waveform)
Solution : im not sure whether ...
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Li-ion cell voltage drops over time while charged from a MCP73831 IC and while USB powers the load
I’m using the diode pair solution from @james in this post with a MCP73831 and a 2000 mAh Li-ion pouch cell with this basic charging circuit:
And then one SS14 diode from Vin to the input of this 5 V ...
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Why does the neon screwdriver (phase meter) light on just by touching the phase wire?
I had a question, can you answer it: as you can see in the picture I uploaded, the single-phase alternating current flows in one wire at one moment and in the next moment from another wire as in the ...
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Is this symbol a TVS diode, and what is the purpose of a TVS diode? [closed]
I'm looking at two similar diodes in a wiring diagram. These diode symbols do not match any of the common diode symbols.
The purpose of D2 seems to be pulling to ground. These diodes somewhat resemble ...
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Is this a valid way to determine which diodes are on in an op-amp based rectifier?
Consider the circuit above, where we are treating the diodes as ideal. Let's take the case where Vs < 0. Since V- = V+ = 0 for both U8 and U9, that automatically means the current is to the left ...
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Solving for V and I in a diode circuit by making assumptions
I want to make sure I understand the solution to this problem from my textbook. The goal is to solve for V and I in the circuit below:
They start by assuming that both diodes are conducting and solve ...
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How to find the values with a voltmeter and ammeter?
I'd like to know how the values obtained in that image are derived.
And I would like to know how to set the transformer in Proteus. What should I set if I want to use a transformer 220 V 24 V 0 24 V ...
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Relation between reverse saturation current and temperature in diode
Suppose diode has reverse saturation current of Is at 20 degree Celsius. How to calculate its reverse saturation current at 65 degrees Celsius?
Note: I know reverse saturation current doubles for ...
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Circuit Analysis - Diode Small Signal Voltage
I'm struggling with this circuit analysis about a pn-junction diode.
I'm given I_D = 1.066 * 10^-7 A when V_D = 0.6V and I_D = 2.2 * 10^-5 A when V_D = 0.8V (all at room temp).
My calculated values ...
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Selecting diode with Vf~300mV at 100uA forward current for reproducing a zero crossing published TI circuit
I would like to build for educational purpose the circuit described here.
I hit a snag for selecting diodes D1 and D2.
The author of the paper recommends:
Select the anti-parallel diodes. Choose ...
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Want to know blown out diode value of USB device
I have a PTZ camera which has 9-pin USB B device. When I plug into to the USB it shows the error power surge. I knew something was burned out and opened the device to check and found out that one of ...
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Why these diodes on AC transformer?
I’m repairing an old jukebox. I don’t understand why there is a diode that is soldered in reverse. Is there more voltage on the cathode than the anode? How does it work?
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Diode in parallel with AC solenoid valve
I have a circuit I'm trying to design to fire both 120VAC and 24VDC solenoid valves. We have relays that work on 12vdc for the coil, and can switch AC or DC. the valves are normally around 30W. I ...
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What happens if I use a regular diode instead of a zener? [closed]
Does the diode catastrophically fail? Does it unreliably breakdown? Does it stop conducting? What happens if I use a regular diode as a Zener diode?
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What is the SMD component (MRY marking)?
I could not find the part number for this component (right arrows).
The component on the left is a Schottky diode, right?
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Will this circuit work for wiring a 3.8v screen into my car's power? [closed]
I'm trying to wire a 3.8V screen, 3.8V battery, and my car's 5V power source together and ensure that the device will be powered by the 5V power source when it's available and that the battery is ...
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Arrangement of this diode
I am using this diode for a protection of a bidirectional line. I want to protect the line for both positive and negative transient. But struggling to find the connection to make sure the diode helps ...
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AND logic gate with diodes not working
I am currently working on an AND logic gate using 2 diodes.
My first logic input is 3.3V/5mA from a Raspberry Pi Zero W GPIO pin.
The second is 3.3V/500mA from a door access system. This input is ...
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How to operate and choose the right components to control an industrial pull and push solenoid using an Arduinuo?
Push/Pull which has a 24 V DC power supply and power consumption of 23/85/400 W.
What transistor and diode configs I should be going for?
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Is this a diode or a resistor? What is the equivalent of this one in the picture?
Is this a diode or a resistor? I am unable to solve this problem of my PCB inverter.
That is the back of the component... pls guide me...
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Method of analyzing circuits with diodes and opamps
This is an exercise from an electric circuits course I had on my first semester of university. We are asked to determine the output voltage \$V_o\$ when \$V_\text{in} = 667 \: \text{mV}\$. The diodes ...
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Help to understand this 5V relay module's diode
Hello people, I need a bit of clarification regarding the below module, especially with the diode that is used. Does anybody know the value of it? If it is 1n4148, is it a Zener diode? What will be ...
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MOSFET body diode current rating vs Schottky diode
How is it possible that a MOSFET's body diode in a TO-220 package, such as the N-channel IRL3803 or P-channel IRF4905, has a much higher average/continuous current rating than a high-current Schottky ...
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Choosing capacitor value and rating and diode rating for Cockroft-Walton circuit
I am building a voltage multiplier Cockroft-Walton circuit that produces around 120 kV output voltage with 15 kV input voltage (initially 250 V is stepped up to 15 kV using transformer).
I have not ...
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Why are R1 and C4 connected in parallel to output in the following dimmer circuit?
I'm trying to understand the following dimmer circuit I found from this website: https://electronoobs.com/eng_circuitos_tut80.php:
Why are R1 and C4 connected parallel to the Triac? I have read some ...
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