Diodes are semiconductor components made from a P-type and N-type silicon material, that allows current to only flow in one direction.
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24 views
AC DC Analysis of diode
in the following circuit:
Im looking to find what \$v_D(t)\$ is given \$V_γ = 0.7 V\$ and \$r_f = 0\$.
Now when doing the DC analysis, find that \$VDQ = 0.7 V.\$
But im having trouble finding ...
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0answers
35 views
conductivity of silicon
Im just wondering if I did the following question correctly:
Determine the conductivity of silicon at T = 300 K if it is doped with donor impurity atoms at a concentration of 1.25*10^16 cm-3. Assume ...
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4answers
73 views
1N5819 diode reading?
I'm trying to find which diode in a charger is bad. I took the 1N5819 diode out of the electronics board and tested it with my multi-meter set to "diode".
What I got was 0000 in both directions. ...
5
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1answer
63 views
Doping concentration in anode region
I'm stuck with this doping problem and can't figure out where to go with it.
The built-in voltage of a GaAs pn junction diode is 1.25 V when the diode's temperature is T = 320K. The cathode ...
3
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1answer
44 views
calculating resistance for LED strips to use as parking lamps and turn signals
I'm installing LED strips in my car's tail lamps to convert it from conventional bulbs to LEDs. I have a understanding of what I'm doing but not the complete knowledge to make the circuit work ...
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1answer
80 views
Routing the circuit for a snubber diode on a PCB?
I understand that the "ideal" place for a snubber diode is across the terminals of the inductive device that generates the flyback. But in the interest of making my PCB design for an Arduino shield as ...
1
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1answer
90 views
Zener doesn't seem to be working
So I'm trying to use a zener diode to limit the voltage across a capacitor - specifically, to 2.2V.
As you can see, I'm using a 9v supply. The zener is in series with a resistor - either 100 or ...
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0answers
50 views
Plot the waveforms for current and voltage across the diode in the circuit [closed]
In the circuit shown in the figure below the switch is closed at time, t = 0.
In the circuit shown in the figure below the switch is opened at time, \$t = t_{1}\$.
\$V_{1}\$ is the dc source ...
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0answers
71 views
How do IMPATT and TRAPATT diodes work?
I was reading some text on microwave devices when i came across these devices.The explanation in the book was very convoluted and difficult to understand. Could some one please explain to me
Basic ...
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3answers
115 views
Charging a low-voltage high-C capacitor. Efficiently
I'm currently upgrading my wind-up torch - upon opening it, I found the manufacturers had been quite sneaky in that the circuit is EITHER windup OR battery powered - worse, the batteries are ...
8
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2answers
130 views
Compensating the forward voltage drop of a diode signal rectifier
I am reading Arts of Electronics and they are showing this circuit:
It says that D1 compensates for D2's forward drop by providing 0.6V of bias. I don't understand this circuit at all. Is the +5V ...
2
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1answer
95 views
Diode selection for truck wiring light application
I need to know what diode I need for a light set up I am working on.
The main current flow through the diode is going to be 9v going to power a 55watt roughly ??? amp bulb. There will be ocassional ...
7
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2answers
163 views
How to analyze this diode circuit?
I am trying to analyze this simple diode circuit by hand, but I can't seem to get too far.
simulate this circuit – Schematic created using CircuitLab
Using circuit lab, it is evident ...
3
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1answer
102 views
How might one “short out” a diode?
Many moons ago, as a kid, I was playing around with electronics and proudly demonstrated my latest project to my parents. In my eagerness, I made a mistake in my nest of wires, and the acrid pale grey ...
3
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3answers
108 views
Diodes in parallel
I need to protect about 5A @ 6V from something stupid like my revering the battery wires when connecting them to the circuit. I thought that I could use 5x 1A diodes in parallel, but it seems that I ...
6
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2answers
171 views
Switching Between Two Voltage Supplies
I have been trying to work out a circuit something like the following:
simulate this circuit – Schematic created using CircuitLab
I want VOUT to be 3V when the switch is open and 5V when ...
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2answers
134 views
Problems when sharing a battery between motors and radio in an RC car
Background
I am building an RC Car that I am trying to modify to control from an Android phone.
When I connect the remote control module as well as the car circuitry (servo & motor) to separate ...
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1answer
43 views
How do we get an “SF < 1” in the reverse recovery characteristics plot of a power diode?
The softness factor SF of a power diode is, the ratio, \$\frac{t_{b}}{t_{a}}\$.
My question is how do we get "SF < 1" when it is clearly visible in the reverse recovery characteristics of a power ...
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4answers
125 views
Why doesn't a diode or transistor get neutral?
As we learn that diodes and transistors are made by some materials, and they are called P or N according to having extra electrons or holes.
If there are extra electrons on n-type silicon (doped), ...
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2answers
48 views
varicap diode cutoff and breakdown voltage
BB 109 is a varicap diode and is used for modulation.
I'm going to use this for frequency modulation of voice signal . Since our voice signal is in range of millivolts. I need to know from which ...
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2answers
96 views
Will the PNP and the diode circuit behave differently?
Need to repair a legacy system that has been discontinued and am considering replacing the PNP based circuit with the diode based circuit.
The input signal (max. freq = 20Khz) is applied at IN and is ...
0
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2answers
80 views
At which negative Vce voltage will an NPN transistor be damaged?
Assuming an open base, how low can Vce go (negative) before the transistor is damaged? Can I protect a transistor by connecting a diode's cathode to the collector and and anode to the Emitter?
If ...
2
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3answers
152 views
Current through a diode - non linear?
I thought I'd brush up on some of my knowledge by going over some of the basic building blocks and I'm at the diode. I've never had to "really" know anything about a diode's current, and if in school ...
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3answers
152 views
Circuit Analysis With Non-Ideal Diodes
I have seen how to do circuit analysis with ideal diodes, that is replace forward-biased diodes with connections and replace reverse-biased diodes with gaps. But the problem is that I want to know how ...
3
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1answer
137 views
Synchronous DC-DC converter and fast diodes
I'm a bit at a loss when trying to optimize a DC-DC converter (Half Bridge) and selecting my MOSFETs.
Up to 200V I get good results (MOSFET switching times are fast ~ 20ns and the anti-parallel diode ...
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2answers
83 views
Testing an automotive relay with a diode
How is it possible to test an automotive relay to determine that the flyback diode is not shorted or open?
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1answer
160 views
How to test if a Near Infrared Emitter and Photodiode still working?
I suspect that my NIR emitter and Photodiode are not working.
Emitter http://www.thorlabs.com/thorproduct.cfm?partnumber=LED1450E
Photodiode http://www.thorlabs.com/thorproduct.cfm?partnumber=FGA20
...
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1answer
85 views
TVS DIODE: Min breakdown voltage and Stand off voltage
Can anyone of you please help me out ?
I have a doubt about the TVS diode characteristics,(V-I). I am listing my questions below
What is the min Break down voltage
Stand off voltage
why VBr> Stand ...
2
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2answers
116 views
Please help with Identifying my diode?
I am having trouble identifying this component. I think its a diode. But I am not sure since I hardly know much about electronic components.
The Component says "22-16 U2" and then has a symbol on it.
...
7
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2answers
206 views
Diode logic computer
Is it possible to build a computer (Turing complete) using only diode logic without transistors? I know DTL was a thing, but from what I could tell, they used transistors to amplify signals.
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2answers
158 views
Voltage doubler or not?
I got a quick question! Is the circuit depicted in the link indeed a voltage doubler or is it just a bridge rectifier with smoothing capacitors?
6
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3answers
340 views
Why do diodes have a voltage drop?
Is resistance what makes a diode have a voltage drop?
Or is it impedence?
If it is electrical energy being converted to light, please tell me what this effect is called.
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1answer
120 views
Can I use more diodes to reduce the voltage off a diode bridge?
I have a transformer labeled as providing 9Vac, 3.36 A. It appears to provide 9.4 v ac according to my multimeter.
It runs through a diode bridge (WAB 040 diodes -- already fried the last version), ...
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3answers
166 views
How do I test how many amps a transformer actually puts out
I have a 120v <-> 9v ac transformer rated at 3.34 amps, but my multimeter suggests that (after running it through a diode bridge), I can get 7+ amps out of it @ 9.4 volts ac.
Can I?
I have a ...
4
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1answer
79 views
Does the line on a zener diode correspond with the line in the symbol?
For a normal diode, the thin line on the component corresponds with the line of the symbol. Is this the same for a zener diode?
5
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1answer
225 views
Using a Zener diode as voltage reference
I want to use a zener diode as a voltage reference to the the PIC18F2550, as the analog V+ reference. I am planning to use this zener diode, but I am not sure how to calculate its values. I am ...
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1answer
225 views
How do I select the Correct Diodes and Resistors for my LEDs?
I've got a 2009 Harley-Davidson XR1200 (that can be seen at the bottom of my bio in my profile).
I've replaced the stock incandescent bulbs with nice looking LEDs; however, the stock bulbs were 2-way ...
6
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2answers
126 views
1N4001 Diode Heat
I'm working on a battery powered circuit that is using a 1N4001 diode to bring the 6V from 4xAA closer to 5V as well as for protection in case the batteries are put in backwards.
The total circuit ...
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1answer
135 views
How can I derive an approximate equation for the forward voltage drop of a particular component?
I have a situation where I have ADC value for a battery voltage and I am trying to re-create and display the actual battery voltage. Fairly straight forward situation but there is a diode drop in ...
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1answer
199 views
Identify these diodes?
I recently bought assorted diodes from here, and I'm having trouble identifying part of a reel of diodes. I've taken a few pictures here.
The ruler is in centimeters. The diode markings are all ...
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2answers
503 views
How does a diode work? [duplicate]
Possible Duplicate:
What exactly does a diode do?
What happens in a diode to make current only flow one way around a circuit? My physics teacher said it was something to do with the metals ...
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1answer
122 views
Diode Bridge in Simulator not behaving as expected
Hi I have a Diode Bridge as outlined in the image below. As you can see I am getting a negative voltage on one pair of diodes instead of this voltage being flipped to positive.
Can you see anything ...
3
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1answer
366 views
What is the difference between “reverse stand off voltage” and “breakdown voltage” on a TVS?
On a transient voltage suppressor, let's take a unidirectional Fairchild P6KE11A for example, what is the main difference between reverse stand off voltage (\$V_{RWM}\$) and breakdown voltage ...
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1answer
262 views
Bipolar Transistor HBridge Motor Driver:
What is the importance of using the diodes shown in this Bipolar Transistor H-Bridge Motor Driver?
3
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3answers
875 views
Is a Schottky diode appropriate for reverse polarity protection?
To narrow the focus a bit from an earlier question:
Is a Schottky diode appropriate for reverse polarity protection?
I'd like to prevent mishaps from a user connecting DC power in reverse, but I'd ...
3
votes
2answers
942 views
Diodes in parallel or series
I am wondering what the effects are of putting diodes in parallel or putting them in series. (like current capabilities, voltage capabilities etc.) Let's say I have a datasheet of a diode. What ...
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2answers
115 views
What happens when I connect the GND of a LDO in a Diode to the real GND?
A friend of mine told me to put a diode between the LDO's GND pin and the circuit's GND. He said the LDO will regulate it's fixed voltage plus the diode drop. Is it true? How does it work?
I am using ...
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7answers
427 views
What do the two series-connected, forward biased diodes do?
This is an example circuit providing a constant current for a laser diode:
What does the two diodes in the circuit do?
4
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1answer
348 views
Do I need a protection diode here?
Here I have an automotive relay (from a scan of a workshop manual I'm afraid) which is rather more complexly wired up than the relays I'm familiar with. In this diagram:
L/Y - +12V
L - From the ...
1
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1answer
139 views
High voltage H-bridge diode
i'm designing a varable-frequency drive with 2 H-bridges based on IR2108 half-bridge drivers. I want it to drive a 220v single-phase motor. Reading the datasheet i got a little confused on choosing ...
