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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Beginners Question Regarding Diodes and IC 4060

Take a look at this popular circuit for a fridge alarm based around the IC 4060 (http://free-electroniccircuit.blogspot.co.uk/2012/02/refrigerator-alarm-schematic.html): One thing I notice is that ...
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How does a Schottky diode work?

There are no spare positive/negative charge carriers on the metal side of the diode, so the spare positive/negative charge carriers on the semiconductor side can not diffuse into the metal and ...
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Why do some diodes have a glass package?

Put simply, why do some diodes such as most Zeners and Schottky diodes have a glass package as opposed to the more traditional plastic package? Is it ease of manufacturing, thermal properties, or ...
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134 views

Make a zener diode out of a MOSFET

Does anyone know if its possible to wire up a MOSFET transistor as a zener diode? I have been happily making normal diodes from my MOSFETs by shorting the gate and the source simulate this ...
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E51A818 = 1N5818?

I have a DeWalt DW9116 charger with a fried diode. This was caused by reverse polarity connection to a battery. It has numbers E51A818 printed on it. The only diodes I can find with 818 in their ...
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84 views

Diode rectification on a device

I have a Peltier (TEC) module, with diodes in series with each lead. (see image below) I'm not quite sure what the specs are for the diode, but it says 130 on one line and SB560 on another, so I ...
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46 views

Laser diode M140 current driver

I am trying to build a driver for my M140 laser diode. I made a circuit following a guide. Then I made a test load. When I change the pot value to the minimum I get a maximum current of <100mA on ...
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808 views

Can an operational amplifier circuit be made entirely out of diode Nand and Nor gates?

I'm not sure whether this question has been asked before, but in researching my question, I came across this user's post (at If-else decision structure using op amps or any other non-programmable ...
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42 views

Modeling diode connected transistor in differential amplifier

I have question about the analysis of common-mode gain of BTJ differential amplifier with active load on the Sedra Smith book. In this book, the differential-mode gain \$Ad\$ is derived based on the ...
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110 views

Is it reasonable to use a current limiting diode in place of a fuse?

I'm trying to source some fast-blow 5mA or 10mA fuses but Littelfuse has discontinued the only reasonably affordable ones I have found. My circuit when operating properly will not output more than ...
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71 views

Diode in parallel with two DC sources

Please help me to find the answer for the following question from Flyod 9th Ed. Determine the voltage across the diode in the following figure, using the complete diode model with r'd = 10 Ohms and ...
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63 views

Center-tapped Full Wave Bridge Rectifier

I'm designing a high-voltage power supply for a plasma experiment. I have a center-tapped ignition transformer (50:1) that I'm using to step up the voltage from 120VAC to 6kVAC and then using a full ...
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76 views

Difference in real diode characteristics vs shockley equation

I was wondering about the voltage drop in real diodes (0.7 V in Si diodes, 0.3 in Ge diodes etc.). According to my experience this drop is linked to the used material, but the shockley equation which ...
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59 views

Using to diodes for OR'ing in OVP comparator

We have the following scenario: over-voltage protection IC (MAX18590/86) is placed in front of a buck regulator in order to protect (obviously) against excess-voltage at the input. Normally the ...
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86 views

circuit diagram for uninterrupted usage of a 12volt 1amp device using 12 volt 7ah battery with auto charging and full charge cut off

I have a modem which runs at 12Volt 1Ampere , also I have an UPS battery of 12volt 7Ah. I need to design a circuit so that during power outages my modem works from the battery. also a circuit ...
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93 views

Choosing the right diode?

What are the general steps and things to know to choose the right diode for the right project?
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Diode bridge working only as half recitifier [duplicate]

I am trying to simulate diode bridge using 12. In the image below you can see the circuit and the simulation of the circuit. So my question is, why does this circuit does not behave as full-wave ...
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58 views

Catch diodes in switch mode power

I am wondering about catch diodes in the context of switching power supplies. I have read all the books that are the norm in designing a SMPS, but all of them don't or barely touch the subject. My ...
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33 views

Semiconductor diode barrier potential

I have little confusion regarding barrier potential (or built-in voltage) and cut-in voltage of diode. Are these are same or what is the difference between built-in voltage and cut-in voltage in ...
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49 views

Battery supplying different voltage

I 'm trying to build a portable device running on battery. It needs power at 2 different voltage: 3v and 4.5v Is doing something like this a good idea ? if so, what type of diode should be used ...
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95 views

Will voltage or current determine a diode drop for this battery charging circuit?

I am using a li-ion battery charger IC that regulates an output to 4.2V. I have a schottky diode in series with the output that then connects to the battery. How do I determine the voltage drop? If ...
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104 views

Low profile capacitor

I am trying to make a 24VAC to 5VDC converter. My constraint is to keep the height of the entire power module to as small as possible (ideally < 5mm) I have the buck converter design with the ...
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33 views

Reverse biased breakdown

Is the reverse biased breakdown of a rectifier diode a reversible process? (that is if the voltage is reverted to a value within the specification range will the diode behave as expected of an ...
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99 views

LM7805 and Zener Diodes

I'm boosting an LM7805 to 16V using Zener diodes in series at the GND pin (pin 2) of the 7805. The Zener Diodes I'm using are 1 of each of the following: 3.3V, 3.0V, and a 4.7V. Now theoretically I ...
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Why are resistors used in a Zener clamp circuit?

A data acquisition channel is fed by a signal which first passes through a clamping circuit as I draw below. Here in the figure Output goes into the data acquisition board after a 8V clamp circuit: ...
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Can I make pulsing light using AC as source, a diode and a LED?

I'm new to this branch of physics hence my stupid question. I know that diodes are used to make current flow in only one way. If I connected an AC source to a diode and the diode to a small light ...
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69 views

How to protect bistable latching 2 coil relay with diodes?

I know that a revers diode is required to protect a DC coil relay. But to protect this relay RT314F05? It has 2 coils, are 2 diodes enough?
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What can this component be?

I have this anemometer (wind speed meter). They provide some specs. But not the circuitry. It basically outputs pulses via a reed switch. So I opened this instrument to see its circuitry. Here is ...
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minority carrier life time? Why is it important for devices' switching speed. Why not majority carriers?

I am trying to get my head around why would and silicon engineer care about the minority life time carrier and how does the minority carrier affect the switching speed of PN junction. Why is it so ...
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136 views

Best way to drop 12V fan to 7-9V? [closed]

So my Xbox one PSU died and microsoft doesn't sell official ones yet, so I bought a third party one and the fan that is in it is a 12V blower fan with 2 wires running right to the board (it says 12V ...
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59 views

Diode identification

I'm trying to develop a replacement for a BLDC motor driver board and since my first attempt resulted in a few burned components now I'm trying to use the same components they used on the original ...
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1answer
82 views

Ideal diodes and applications

simulate this circuit – Schematic created using CircuitLab Question: The input signal V(s) is a square wave of \$\pm\$20V (peak) at 1Hz. Sketch the output waveform V(o). Clearly mark the ...
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Solving Clipper Circuit containing battery and resistance in series

I have learned to solve clipper circuit with and with out battery in parallel to the output node. But have no idea what to do if a resistance also connected with it in series. There is nothing said ...
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Understanding the PN-Junction Built in Voltage

I don't like asking duplicate questions but I couldn't find one that was quite the same. I apologize if it is similar to another. TL;DR: How can a charge neutral substance have a potential? Why ...
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Zener diodes Eagle library

I need to make a PCB, and the only software I have is Eagle. All the other parts are listed in my libraries, but where can I find a library that has DIODES INC. - MMSZ5226BS (Zener diode)?
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What is the diode for in this 555 circuit?

Here is a schematic of a 555 setup to create a single shot voltage sawtooth pulse across the capacitor C2. It also outputs a square wave pulse on pin 3. A (reversed biased) Zener diode is used ...
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Considerations for solar powered thermoelectric cooler with fan

I am building a food cooler for camping this summer. My plan is to build a thermoelectric cooler that is solar powered. My cooler is looking much like this: including a CPU fan on the hot side ...
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Car Gear Indicator [closed]

I'm new in here and I'm very new to electronics and have a very little knowledge about it. I'm trying to do a project in where I have a car with manual gears 1,2,3 & 4. Each will be represented by ...
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63 views

Standard doping concentrations for Si and GaAs Solar Cell (as well as other standard values)

I am doing a MATLAB project where I need to plot the current of a Silicon and GaAs Solar Cell under Air Mass 0 and Air Mass 1 conditions. I have used solar irradiance data to calculate their ...
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DC or (AC + DC) coming out of a full wave rectifier

DC or (AC + DC) coming out of a full wave rectifier Is there a truly correct answer to this? Considering the representation as a waveform I would say its an AC wave form offset by some DC amount. ...
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74 views

How does Diode-Resistor Logic Work? [closed]

I don't understand how diode-resistor logic works. How do they output a logic 1 or 0?
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How Fuzz (audio effect) works?

I am relatively new to the world of guitar pedals, and I have recently (after a few failed attempts) built a successful Bazz Fuss. Although I've successfully built it, I'm not sure how exactly it ...
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Designing a low voltage UPS

Preface: I am designing a UPS such that if the AC main fail the device can continue to run for at least 10 days. My goal here is to make a design that can last years off a non-rechargeable battery. ...
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Is this a Zener Diode? UPDATE it just turned into dust :( phone still turns on, what the…? O_o

my Nexus 4 usb connection died and when opening it I found a burnt component which looks like a zener diode, it could be a transistor though, I need help identifying this component so I can replace ...
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128 views

Intrinsic Zener diode in MOSFET

I understand why some transistors have a built-in (normal) diode from drain to source, so that when the transistor turns off, back-emf can flow back up, specially important in inductive charges, but ...
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55 views

Replacing a diode

I have a 24V battery charger that got wired in backwards and it fried one of the diodes. The codes on the diode are: STPS30 150CW U4D409 I have found one which I ...
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2answers
126 views

Should a rectifier or TVS diode be used as a flyback diode?

I'm trying to design a circuit for a relay similar to the following (except using SMT components): When I went to Mouser to try to find a suitable SMT diode to use in place of the 1N4001, I noticed ...
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360 views

How to choose a flyback diode for a relay?

A diode is put in parallel with a relay coil (with opposite polarity) to prevent damage to other components when the relay is turned off. Here's an example schematic I found online: I'm planning ...
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Zener Diode Identification/Replacement

I am seeing if I can trace out remake some circuit boards laying around. For this particular board, I can identify all parts except this diode. The part number is CK 2EZET (I am only assuming it is ...
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Finding required maximum current rating for a diode which will run in PWM mode

Consider a diode rectifier which will transfer a PWM signal. The duty cycle rate of this PWM signal is \$D\$ (\$0 \le D \le 1\$). The diode on state current is \$I_{ON}\$, and no current will be drawn ...