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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dynamic resistance of PN junction diode

I am lost here, I was wondering what voltages do I have to include in the equation that is asked for both v1 and v2? and how do I do that?
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36 views

Diode reverse recovery charge

I am trying to model a switched mode power supply and I'm working on semiconductor losses now. I discovered how switching looses are affected a lot for diode's reverse recovery charge. The problem now ...
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59 views

Why to double reverse diodes in parallel to MOSFET?

I am building an H-bridge by this article. In the H-bridge MOSFETs IRF9530 and IRF530 used. By datasheet of Vishay both of MOSFETs have reverse diode inside the package. So by proposed schematics ...
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36 views

Why is there a “ - 1” in the pn-junction current equation

I was studying the Ideal Current–Voltage Relationship and was wondering why there is a "-1" in the pn-junction current equation for a pn junction diode.  Thanks in advance!
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1answer
155 views

choosing diodes for a passive ethernet hub

I found several guidelines for building a passive ethernet hub, mostly quoting this. The guide specifies which diodes to use, but I cannot find them anywhere. What are the parameters I should search ...
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207 views

Max voltage vs current for LED

There's some basic flaw in my understanding of how LED's or diodes in general work so hope someone can help and forgive the simple question. So generally when one has an LED in series with a ...
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4answers
264 views

Floating diode in a Sot23 package

I have a schottky diode in a sot23 package that is composed by 2 schottky diodes with a common catode connection. I need to use one of them. Should I let the second floating with unconnected pin or ...
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4answers
546 views

Does it mean voltage across diode is zero?If yes, then is zero voltage across diode condition for forward bias?

When an ideal diode is forward biased, it is replaced by a connecting wire .Does it mean voltage across diode is zero?If yes, then is zero voltage across diode condition for forward bias?
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3answers
82 views

What is the voltage source and ground on an antenna?

I've seen a few diagrams relating to AM demodulation, and I can't for the life of me figure out where the voltage source and ground come from in an antenna. From what I understand, an antenna can ...
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1answer
74 views

Diode selection [duplicate]

I have a very simple circuit but have no idea on what or how to chose a diode for it. It is for a uni project and we are being marked on our justification for choosing the diodes. Is there such ...
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1answer
131 views

What is is an “M7” Diode

I know what it is in general terms of course. But I mean specifically what does the M7 mean. I certainly can't just go to digikey and order an M7 diode because such a part does not exist. I'm making a ...
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83 views

Choosing a correct diode

I am trying to find a suitable diode to place on the wire that connects c and e in the circuit, with the cathode on the right hand side. I need to justify why I chose the specific diode as well. ...
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1answer
66 views

What are the correct zener diode and PTC fuse size?

Noob here. I need to add overvoltage protection to a small, portable solar power system I'm putting together. The solar PV array has a loaded voltage in the 23-26v range and an open circuit voltage ...
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1answer
98 views

Using diodes to increase efficiency

So I have the schematic below and I am to insert diodes into the circuit to increase the efficiency of the circuit (can only insert diodes, not change the wiring). 'Target' is where I want the power ...
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1answer
34 views

Example circuit with an F12C20C dual rectifier?

I've salvaged a MOSPEC F12C20C Dual Power Rectifier from an old PSU. I've been looking for example circuits that would use this component, and an explanation of how it works but I've only found its ...
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2answers
146 views

what happens with diode voltage drop when connected directly to constant voltage supply?

The diodes usually have voltage drop of about 0.7V or so, which is said to be constant for some type of diode (ie. not depending on voltage/current). So what would happen if one connected a diode ...
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329 views

How can an op-amp act as a precision diode?

I read in an article on application of op-amp that it can act as a precision diode. Precision diode is an ideal diode having very much less forward voltage drop. I am not able to understand this ...
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92 views

open collector digital output

I have a digital output board design which has 32 open collector (sinking) outputs which can be connected in parallel to drive a resistive load. The collector of each output transistor is connected to ...
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1answer
49 views

is there a difference between these 3 diodes?

http://www.mouser.fr/Search/Refine.aspx?Keyword=1N5819-E3/73 1N5819-E3/73 1N5819-E3/53 1N5819-E3/54 the first one is 4x cheaper than the last, why ? aren't they all the same ?
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319 views

Relay's Flyback Diode - Is it necessary?

I have four 6V, ~80mA Relays mounted on a Perfboard which are being controlled by the 2N2222 Transistors. The basic problem is that after mounting everything the diodes can't fit in easily. Is the ...
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49 views

how to find a cutoff frequency from a diode datasheet

I have with me the rise time= 1000ns fall time=500ns pulse width= 10microseconds. I want to find the cut off frequency. I need to use this to find the cjo of a diode can I use this formulae ...
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61 views

H-Bridge flyback diode selection?

I am wanting to make a motor driver using a SN754410 Quadruple Half-H Driver IC. The SN754410 requires external flyback diodes. Here is an example circuit: My question is, how do I choose which ...
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136 views

Why should a diode be placed parallel to the coil? [duplicate]

I'm looking at connecting relays, In the schematic found on this site, the diode is placed in parallel. Why would this be the case? If the diode is there to circumvent large voltage flow back, ...
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113 views

Not understanding a circuit from a book im reading

Well Hello and merry xmas! , I got a qeustion of a circuit witch i dont understand (yes its probaly a stupid qeustion but i cant figure it out) So this is the text from the book . Because of ...
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136 views

forward or reversed biased?

Is it reverse or forward bias? in real life and theoretical for example: Voltages in the pic are 10V What if I placed a resistor in series with the source on the right?
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61 views

What do the numbers on a zener diode signify

I have a zener diode obtained by reverse engineering, there is an icon of what is surely the mathematical model, and there are two numbers 41 and underneath 48, what do these signify?
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Schottky Diode disadvantage as compared to usual diode [duplicate]

Schottky diode have a low forward voltage drop (typically \$0.15-0.45V\$) and very fast switching action, as compared to traditional diode, which typically have a \$0.7V\$ voltage drop (Silicon ...
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Properties of transitors used as diodes

Consider the NPN BJT. Normally, if you want to use it as a diode, you short base to collector and treat the emitter as the cathode. But in principle, you could also use the base emitter junction by ...
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47 views

Flyback (?) diode on the Solid State Relay output

I am looking at the recommended wiring diagram of this SSR and I am wondering about the diode connected in parallel to the load. Flyback diodes for inductive loads make perfect sense to me, but in ...
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70 views

Diode detector strange discharging

I am building a diode detector circuit in order to detect ASK signal with 125 KHz carrier frequency and 8 KHz data rate. However, I realized I would say a strange behaviour and discharging of ...
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355 views
+200

Replacing a Switch and Avoiding body diode conduction

I am trying to design a replacement for a 2:1 switch using FETs, which would be really easy if I didn't have to concern myself with the body diodes that are present on PMOS transistors. My scenario ...
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3answers
105 views

How does a constant current (CC) power supply regulate voltage (V) in parallel circuits?

I see that some power supplies provide a wide range of output voltages meanwhile maintaining the current. For example: 2.7 A, 20-36 V output. I understand that the voltage rate will depend on the ...
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46 views

Series diode voltage clipper, on Multisim clipping and shifting on positive and negative voltage

This is my circuit: I’m testing a Series diode clipper circuit, and the end result should be this: (I've used 5V in my circuit, not 10V like in this plot, but this is not the issue) Instead what ...
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79 views

What's the difference between IC 74HC04 and IC 74AC04PC?

I am trying to make a simple logic gate simulation for which I require the former IC but I could only procure the latter. Will it still work?
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Why avalanche breakdown in a PN junctions is said to be caused by minority carriers?

Reverse bias increases the depletion region (the "space charge region"). Remembering that electrons travel from (-) to (+) terminal, and that in reverse mode the (+) terminal is attached to the ...
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Half-wave recitifer diode (0.7v) problems

I can't seem to decide which is the correct answer for this question. An ac voltage of 5 V (peak) is applied to the circuit shown. What is the peak inverse voltage (PIV) of the diode? Silion diode ...
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57 views

Reading Diode Datasheet

I am learning about Diode and its use (Just get interested in electrical stuff after reading a DIY project), I have been reading information around and want to get more understand on diode especially ...
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49 views

Replace Panasonic ML421 battery

I'm trying to replace a rechargeable ML421 battery in my old Panasonic FX100 camera. The specs of the old battery are here ...
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139 views

problem regarding AND gate using diode

I am currently having problem understanding the basic circuitry of AND gate using diodes and how it works. As we know, the basic AND gate circuitry using two diodes is something like this. And we ...
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36 views

opamp input protection for piezo as microphone

I have a Piezo buzzer that I made into a contact mic, across a 1Meg resistor. That goes into an opamp that I use as a differential pre-amp. I'm thinking I should add some diodes to protect the ...
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28 views

To find the current of a current mirror circuit

In the figure given above all transistors are matched and! diode voltage and Vbe = 0.7V. Also the dc current gain is assumed to be very high. I got the answer for I as 3.6mA. However, the answer ...
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66 views

Limiting small signals to one direction (ideally with passive components)

My setup is as following: I use a Y-Cable for splitting an audio signal to two devices (boxes and earphones). The headphones have quite big speakers so they act also like a microphone - feeding back ...
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122 views

The “AND” gate function

I am learning about the "AND" gate function in Navy school. What I know is that when a low voltage is at the base of Q1, the transistor is in cutoff mode since the collector is reading high (> 2 ...
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36 views

Function of diode-connected transistor [duplicate]

Can anyone explain to me how a diode-connected MOS transistor works especially intuitively?
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1answer
54 views

How the Depletion Region is shrinked when Diode is in forward biased?

I would like to know why does the depletion region gets shrinked when a potential is given to a diode(Forward Bias).Is it because we have given a higher voltage than the voltage of the depletion ...
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Dark current of photodiode gets higher after heating, why?

I'm doing some experiments using photodiodes. I raised the temperature to about 1000 degree Celsius for 1 second with melting AuSn near the PIN junction. Then the dark current of photodiode is higher ...
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1answer
65 views

Will a tvs diode help my relay with inductive loads?

I am not an EE, so please be gentle! I will obviously get a certified EE to review my design before anyone else touches this so please assume that I know enough to at least be safe with 120VAC and am ...
3
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1answer
43 views

Load lines and Esaki diodes

I wanted to check something I was working on, and it's an assignment so I don't want the answer, I just want to know if I am approaching it right. I have an esaki diode. I have a curve (the s-curve ...
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2answers
99 views

Long term effect of over-voltage on clamping diodes and ADC reference voltage

I am contemplating building a small voltage/current monitoring circuit that needs to monitor a wide range of voltages and currents. Currents will just be a single low-side shunt. Monitoring will be ...
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2answers
83 views

How does reverse leakage current of a Schottky diode come into play with a SMPS?

Looking at diodes for a low power switch-mode power supply I'm designing. I'm not quite sure what the reverse leakage current value is, or if it's relevant in the component selection.