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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Can you use diodes instead of OR gate?

I am building a computer and thought if I could simply use diodes instead of OR gates. Will this work with logic ICs such as the 74LS, 74HC and 75HCT series? Sorry if this is a stupid question, I am ...
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2answers
89 views

smd resistor and regular through hole resistor

My question is fairly simple. I am building an SMD LED board and i am limited in space. So originally i was planning on going with through hole resistors, but have it being i'm very limited on space ...
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4answers
200 views

Zener diode voltage too low

I'm trying to regulate 12V to 4.7V with a zener diode. (I'm doing this to protect an AVR's gpio pin, so the current is very low.) I tried the simplest circuit with the zener, but it does not work as ...
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1answer
25 views

Discrete IC Printed label

How can I identify a transistor PMOS, when I only know the printed label/legend in it "T9F"? and the same to identify a zener or diode, when I only know the printed label/legend in it "2U90"?
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1answer
23 views

Does zxms6004ff come with flyback diode internally?

As question above, does anyone know better about product from DIODES? I am using zxms6004ff, but not sure about if it comes with flyback diode internally? I read over their datasheet. It only says it ...
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1answer
61 views

When current flows why diode not makes any shortage in it

I konw that a diode works like the explained here. How does a diode work? but I have different question as I am not expert in Electronics, well i am showing you a very simple circuit which is below. ...
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2answers
50 views

Choosing Diodes for 3-Phase Rectifier

I'm building a rectifier to rectify a 3-phase signal for part of a school project, so I'm not working at these power levels without help and supervision. This seems to be an appropriate circuit as ...
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3answers
39 views

Question about Z-Diode circuit and measurement

I am currently diving in in embedded development using ATMega Microprocessesors. I have now a question regarding Z-Diodes. My circuit is powered by a 9V battery that gets through an IC7805, thus ...
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1answer
43 views

If you put a MOSFET in backwards does the impedance change?

if I stick a MOSFET that should be going (S-D) to positive in backwards, and make it (D-S) to positive, all the current drops across the diode instead. This diode then approaches an impedance of 0. ...
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0answers
22 views

which type of rectifier would you use diodes with a (P I V)rating of 50 V??and Illustrates

For a peak output voltage of 45 V . In which type of rectifier would you use diodes with a (P I V)rating of 50 V??and Illustrates
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1answer
60 views

Will a diode conduct if one side is floating and one side has voltage applied to it?

I have a circuit that has a battery output voltage of about 7V and can also have a charger input that when plugged in will output around 9V. The battery/charger power a microcontroller (regulated ...
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3answers
49 views

best way to rectify 30kv flyback output?

i have made a flyback transformer for some HV experiments and am hoping to get around 35kv from it, which i want to use to charge a capacitor, so i will need to rectify the output... i think perhaps ...
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1answer
48 views

Zener diode minimum and maximum current

Why is the Iz max given before Iz min in this zener diode catalog? If you look at the list of diodes at the bottom, you can see that the maximum test current is given first. Is there something ...
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1answer
67 views

Diode in parallel with resistor

SE, I've used the SE:EE forum search and several search engines internet and haven't found a single question similar to mine. But I don't think that it's that complicated, I'm just having a hard time ...
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0answers
63 views

Current sensing in H bridge for Stall detection-Purpose of Diode

I have a circuit, which is powered from two 1.5 V AA battery. It has a MCU and PNP - NPN Hbridge for driving motor. The motor (RF-300CA-11400) datasheet is here in this Link. The Motor will be turned ...
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1answer
29 views

AC alternative for DC diode short-circuit protection

I have two sensors (represented in the schematic below by a switch) connected to a light. If one of the sensors trips, I would like the light to switch on. The sensors and light are directly on AC, ...
0
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1answer
65 views

Can I replace a 1N4148 diode with a 1N4007?

My PC game controller broke and since I have some old PS1 controllers I was thinking about converting one to PC. After some googling I found all I need is a parallel port plug and some 1N4148 diodes. ...
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3answers
92 views

What's the purpose of the diode in this selectable supply voltage circuit part

I'm looking at the power supply part of the schematic of SparkFun's Pro Micro Arduino board, which has a jumper to enable or disable a voltage regulator to select between running the board at 3.3V or ...
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1answer
49 views

1N4148 Diode for 3V-5V PWM

I have 2 PWM ports, one generates 5V PWM and another at 3V. But only 1 will be generating at a time. However, their output is going to a same wire or pin. So, to avoid the current to pass into each ...
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1answer
55 views

Solar panel strings: when does current flow via bypass diodes where each panel has a different maximum power point?

When having strings of 5 till 6 a-Si/µ-Si thin film PV panels and each panel its junction box is containing a BY255 by-pass diode, to make sure that current will flow in less optimal situations, like ...
0
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1answer
51 views

How does a diode valve work based on this sentence?

In a diode valve, the anode would not emit electrons when heated so when the polarity of the voltage across the tube was reversed, no current flowed. Notice how the solid state transistor works in ...
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1answer
68 views

Clamping Diodes - Any disadvantages form continuously clamp down?

I am looking at using Clamping diodes to protect my Raspberry Pi UART pins from over voltage. The ESD Diodes I am looking at using My question is, is there any harm in them continuously clamping down ...
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1answer
25 views

Capacitive ECG electrodes and capacitor discharge

I am trying to make ecg electrodes with capacitive coupling. Since my capacitor is only about 10 pF at max and I have to have as low cut-off frequncy as possible, I came up with a circuit like this. ...
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1answer
54 views

How do I clip voltage between ±0.5 for ADC input?

I have an ADC which accepts 0.5 to -0.5 V for input. How do I clamp the voltage at the input of the ADC to assure protection and maintain voltages between 0.5 to -0.5? Any Suggestion?
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3answers
69 views

How to properly connect and drive varicap diodes?

can someone explain me how to connect and use varicap diodes? Please consider that I am a novice, so would be ok to use a clear and an exhaustive language/terms. Thank you. I often see these ...
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1answer
52 views

Negative Inputs For Diode Transistor Logic

I 've implemented this basic logic gate on a breadboard. Only my circuit has +5 supply voltage. The resistor values are 10K for diode inputs and 1K for collector of the transistor. The transistor ...
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3answers
83 views

Difference between 1N914 and 1N4148 diodes

I always thought that the 1N4148 was an improved replacement for the obsolete 1N914, but I see that the 1N914 is still produced, and overmore, looking at the parameters for both on digikey they seem ...
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2answers
64 views

Total current at the load?

Assume the voltages sources(InducedV1/V2/V3) are created by an inductor/or a strong magnetic field changing rapidly(or in anyway) the PS would power the load, however, there are induced-EMF's V1 in ...
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2answers
75 views

Will current flow beyond the diode?

V2 is blocking any current passing diode(1) because of the voltage being higher,however, V3 is equal and opposing V2, therefore canceling out and allowing current flow through the diode? ...
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0answers
49 views

PIN Diode T-R Switch for use with RF Power Amplifier

I would like to use PIN Diodes to actuate the T-R switching of my RF Power Amplifier, however, I am having trouble understanding the proper way to accomplish this. I would rather use a solid state ...
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4answers
107 views

Optimize PNP/Diode Schematic

I am trying to design a circuit which has four switches, numbered 1-4 as in the diagram. The circuit should function such that closing switch n turns on light ...
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1answer
87 views

My Circuit is leaking voltage. What diodes\methods can I use to fix this problem [closed]

Okay so here's the deal I am using these items in parallel to power one load in order to supply enough current (3A max) at a constant 5V. I won't get into detail about why exactly I'm using ...
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1answer
61 views

Diodes between rails

I recently saw a circuit that implemented a BAV99, which is just two diodes, between +3.3V and GND. How does this work? Based on the spec sheet, the fwd voltage varies based on the current. Am I to ...
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1answer
40 views

Related to varactor Diode?

I'm working on my project during this i face some problems... Here i mention my problem:- I required some variable capacitance whose range is C=0.05pF to C=0.5pF. So there is any variable ...
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1answer
48 views

Tunnel diode I-V curve noise [closed]

Wikipedia gives this example of an I-V curve of a tunnel diode. What is the "noise" in the negative resistance region? Is it a characteristic of the diode or of the measuring circuit? The caption says ...
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1answer
39 views

Determine I through load resistor in circuit with diodes in series

I'm trying to find an expression for the current through the resistor \$R\$ when the AC-source is at max voltage of 5 volts. \$U_T\$ represents the voltage drop across each diode. \$R_D\$ represents ...
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41 views

Working of 2 input AND diode register?

According to the description that I am reading in book it says that you need to connect +Vcc to both the A and B in order to get the output 1 at Q. I don't really understand this. What does the ...
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2answers
105 views

Does the voltage drop “pass” like current?

Q: Suppose this diode is silicon. So it can't have more then 0.7 voltage drop. If,after the diode has aquired 0.7 volts, more voltage comes from the voltage source,then what happens? Does the diode ...
9
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3answers
284 views

Is it safe to treat a system downstream of a reverse-biased diode as de-energized?

Suppose I have a 480 VAC line, feeding a rectifier and filter caps. Obviously this is not something to be trifled with while live. Now, suppose there are blocking diodes coming off the DC bus, as ...
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1answer
65 views

TVS Diode selection

I am designing a motor controller for a 24V 2.2KW d.c motor but I have a problem. I have been unable to get the 1.5KE39CA TVS Diode spcified in the design guide i am following. But i have two ...
3
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2answers
79 views

Please explain the circuit (current regulator test circuit with Zener diode)

my mind needs refreshing so could someone please help explaining analysis of this circuit. It is used for testing a current regulator (LED driver circuit) ('I' in the image). The regulator current is ...
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1answer
28 views

Fundamental difference between DC IV measured current leakage and AC CV measured conductance

I am a physicist with an general EE measurement question, thanks in advance for the advice! I am measuring the properties of a majority carrier diode that I am designing, and usually just take DC IV ...
5
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1answer
383 views

How protective diode protects transistor from breakdown?

Please, explain the process of breakdown; how exactly this protective diode protects the transistor? In a Horowitz & Hill book, "The Art of Electronics", 2nd edition, in "Chapter 2 - Transistors" ...
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36 views

Dc Motor drive setup

I would like to ask why in this setup the dc motor is parallel to the fet and what is the reason for the diode. Thank you!
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1answer
125 views

“zero voltage drop diode”…Really?

In my research for this question, I found this by a new user that hasn't been seen before or since. His low investment here and the "say goodbye to traditional bad stuff" language makes his answer a ...
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2answers
77 views

How to analyse this diode circuit

what will be the voltage at Vx if D1 and D2 are practical diodes This is not a problem from some text book. This circuit came in my mind while i was studying differential amplifiers.
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1answer
43 views

Controlling the current through a Diode Bridge VCF

I'm investigating different analog low pass filter circuits and came across this Yamaha patent which ingeniously utilizes a diode bridge as a variable resistor. It takes some reading but in short: ...
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2answers
80 views

Alternative ways to maintain temperature stability of silicon BJT circuits other than feedback resistors

So I've been messing with Bipolar Junction transistors lately and I'm trying to really nail the concepts of designing circuits with these things cause I want to start using them in some of my circuits ...
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0answers
62 views

Are Germanium Zener diodes still obtainable?

I need a Germanium Zener diode for a shot noise generator circuit. If I am correct, Silicon replaced Germanium for use in diodes and other semiconductors because of the fact that Germanium diodes have ...
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1answer
69 views

Exceeding voltage ratings on microcontroller pins using series resistor

I've been designing a circuit which requires a microcontroller to read a voltage above its current VDD or below its current VSS. I've done this once or twice before by putting a large-ish resistor in ...