Questions tagged [zener]

An effect in semiconductors, the name of a diode that uses that effect and more generally any diode that has similar characteristics to a zener diode. Zener diodes have the unique characteristic of a reliable reverse bias breakdown voltage. Often used as simple voltage regulators or level shifters. Zener breakdown is a distinct effect common usage is any diode that has a fixed reverse breakdown are called "zeners" even if the mechanism is different.

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Simulation doubt with Zener diode & MOSFET

I have the below circuit in which I am trying to perform simulations. Simulation Tool used - Falstad Simulator 12V Zener Diode Top MOSFET Bottom MOSFET Question 1 : The Zener diode is 12V Rated. I ...
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Purpose of this Zener diode (reverse protection)

I have the below MOSFET circuit: Zener diode - Datasheet N-channel MOSFET - Datasheet I want to understand what is the purpose of the Zener diode D5202 and at what conditions does the Zener diode ...
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this should be done using LTSPİCE [closed]

PLEASE,this should be done using LTSPİCE
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What component is this? Need identify

What component is this? It's from a led light strip on a backlight on a car.
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Problems related to Zener Diodes to determine the ratio of transformer

I am having a problem which is related to a circuit as shown below: simulate this circuit – Schematic created using CircuitLab I will give you more information about this circuit. V1 in this ...
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What will be the effect of adding a 10k load resistor to this circuit?

Background When ignoring the 10k Resistor: When Vsupply = 28V, I have worked out that the current through ZD1 = 4.95mA. When Vsupply = 14V, I have worked out that the current through ZD1 = 4.9mA. ...
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How much zener needs current to regulate voltage?

Is there some lower limit how much current is needed to keep zener regulating voltage. I think I have read that it will require some amount to operate reliably but how can I say what is not enough and ...
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How to find supply voltages in zener diode regulators

A simple Zener diode voltage regulator is under design. The design constraints are: Supply voltage: Vs = 150 V Zener voltage: Vz = 50 V Zener current range: 5 mA≤ IZ ≤ 50 mA (a) Determine the value of ...
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Choosing a zener for dynamic Rload variations

I am attempting to simplify a schematic by using a zener diode as a regulator for a small radio. At peak, the radio will consume about 50mA @ 3.3V, and in its low power sleep state, virtually nothing (...
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Detect Battery Insertion in USB Charging Circuit

I'm using an MCP73831T as the charger IC, I've figured out how to detect the charging/charged, this was easy, however, I would like to know when the battery is actually plugged in, I know when the usb ...
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Are there errors in the description of this circuit?

Background The circuit describes the operation of a variable voltage power supply. In the description below the circuit diagram there are errors. Read through the description and note down any errors....
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Zener diode with breakdown voltage of 12V. How to plot a graph of V vs I indicating all important points?

I am bit confused with the question here, because as per my understanding if the breakdown voltage is 12V, then if they are connected in opposite directions there will be no current flow through the ...
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What is the function of zener diode in the fig and power dissipated in zener at No load condition?

If supply is producing max 20mA at 9V what will be the value of Rz? To improve the current capability, how can we use NPN transistor instead of diode here? Ans: According to my understanding, it is ...
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Zener diode and voltage regulation

I have thought about the below question a lot but i can't understand how to go ahead. The question appears to be wrong to me. Any help or even a comment will be appreciated thank you. A Zener ...
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What is the Zener Voltage?

May anyone of you please point me, how to order this Zener Diode? I have done reverse engineering to this switching power supply, yes it is a Chinese sound amplifier and there is not official ...
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Using a Zener to offset split rail?

simulate this circuit – Schematic created using CircuitLab i've searched but can't find a definite answer, is it possible to use the standard resistor divider but with a Zener in the middle to ...
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Zener diode function in ringing choke converter

I'm referring to this video which I saw on youtube. I'm not sure the effectiveness. video 1 In this video, it shows that by increasing the zener diode value from 6.2V to 11.8V (by connecting 6.2V and ...
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Reverse Polarity Protection Circuit with P MOSFET and Zener

I have been trying to understand the operation of the following polarity protection circuit (Diagram doesn't show the internal body diode of MOSFET): simulate this circuit – Schematic created ...
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Zener diode at the output of High-Side Buck Converter

I'm designing a buck converter based on UCC28881 and this Reference Design. The datasheet for the UCC28881 states that: 9.2.1.2.5 Pre-Load Resistor (RL) The pre-load resistor connected at the ...
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How to protect an input from ESD?

I would like to protect the input of a sensor (reference : MAX30001) from ESD. In the datasheet, they say that the absolute maximum rating of this input is -0.3 V < Vinput < 2 V. Do I have ...
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Signal Conversion 36V to Logic Level with Zener Diode

I have 8 cells in series and I want to check them, whether all are connected. I came up with the following schematic: simulate this circuit – Schematic created using CircuitLab My question is ...
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What will gain be when both the zener diodes are conducting?

I have seen in solution that they have considered both 10k and 20k to be parallel when both the diodes are conducting. How will 10k and 20k be in parallel when zener diodes are conducting? Why are we ...
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Identify the Maximum Voltage that can be applied across Zener, MOSFET and Transistor

In many Zener Diode datasheets, I have witnessed that in the Absolute Maximum Ratings section, they don't include the "Maximum Voltage" that can be applied to the Zener diode. If the applied voltage ...
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bicolour LED voltage threshold switch

I'm a long time reader of this site but my first time as a poster. In my scenario I am using a 6V AAA powerbank and want to have a simple indicator to tell me if the batteries are nearly flat say at ...
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Does anybody know or can please verify if my solutions and answers are correct?

Solve for Vout If R3 is a potentiometer, what must be its value if desired VOUT=24V. What must be the range vaue of R2 if the desired Vout is 10 - 25V? R1=125 OHMS, VREF=1.25 V
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Turning on an automotive relay when enough voltage is avaialble

I'm trying to drive a relay off a dome light in a car, where the dome light fades in smoothly. That is, say, I have a constant ground and the other wire goes from 0 to 12V (up to 14V) over a couple ...
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Maintaining LM2596 output voltage with switch

I'm simulating an LM2596 DC-DC voltage regulator to give me a 5-volt output given a 5 ohm load (1 amp). The circuit is shown below: simulate this circuit – Schematic created using CircuitLab ...
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Safely powering Dell laptop from external Li-ion battery with a 11.1V/19.5V step-up converter

I need to build a power-bank type device for my Dell Latitude 6530 laptop (19.5V, 90W nominal power input). I have 12 Li-ion 3.7V, 3.35Ah (18650-type) cells, 3S4P configuration (11.1V total output). ...
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Difficulty using CircuitLab to build a Zener Diode Voltage Regulator Circuit

So I'm trying to build a Zener Diode Voltage Regulator in CircuitLab. I've been searching around Google for some insight into building these, however, I'm required to use a triangle wave input, ...
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Power Supply Filter detection using Zener diode and PNP Transistor

I want to understand the below circuit which is supposed to detect voltage if it goes beyond a certain limit. The Input voltage is between 15V-30V. The circuit means to detect if the voltage ...
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Circuit analysis with Z-Diode

Is there a clever way using KVL and KCL to calculate the voltages across the components in this circuit: simulate this circuit – Schematic created using CircuitLab If there would be no ...
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1answer
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Protect Jack plug circuit against transients and constant voltage

I have a question regarding input protection of a circuit. I have been looking all over the internet for awnsers, but can't seem to synthesize the right solution for my problem. To make my question ...
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Strange effect of adding resistor to the circuit

Here is the circuit: And this is the simulation settings: Because D1N4468 is 13V Zener diode, the temperature coefficient is positive and so the breakdown voltage should increase as temperature ...
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Voltage lower than expected (voltage regulation)

I am attempting to make a voltage regulator. When I make the circuit below but without anything to the left of the dotted line I get the expected voltage; however when I make the full circuit the ...
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Help - Battery discharge protection circuit

I am working on a LED (3 V/20 mA) torch circuit powered by 3.7 V/1000 mAh Lithium battery. Am planning to add discharge protection feature to this circuit. If battery voltage go down to 3.3 V the ...
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6.2 V zener shows lower voltage (Multisim)

I have this circuit with a 1N4735A 6.2 V zener diode. I am trying to figure out why am I measuring 5.1 V across it. The circuit is a transformerless power supply with more or less 60 mA of maximum ...
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What is maximum and minimum current through zener diode?

For a simple electronic voltage regulator using Zener diode, I use the following circuit. For deciding Rs and RL, I need to know Izmax and Izmin of the zener diode 1N4736A used. From this data sheet, ...
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Problem with Op amp and zener diode circuit

I have the following problem. Consider the circuit below: The resistors have the resistance \$R=1000 \Omega\$. The zener-diode has the breakdown voltage \$V_{break}=2\mbox{V}\$ When \$V_{in}=-3 \...
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Custom zener diode in LTSPICE [duplicate]

I want to use the diode 1N4571 (Vbrkdn=6.4V) and 1N4761 (Vbrkdn= 75V) in my circuit. Please help me design these zener diodes in LTSPICE.
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How prevent discharging static electricity when touching metal case of sensitive circuit?

I have made a metal box including raspberry pi, touch screen and lcd screen. my problem is when i touch the box static electricity cause arc and shock to device and cause software failure also. i ...
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What is the function of Zener diodes in an astable multivibrator?

I came across this schematic in my textbook which has back to back Zener diodes connected to the output of an astable multivibrator using op-amp which apparently varies the peak to peak output ...
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LED voltage indicator - why don't these LEDs blow?

I want to make a simple voltage indicator for my 75VDC power supply. I was thinking one LED for ~12V, one for ~40V, and one for 70+V. I found this simple instructable online, which, for 3V-30V, ...
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Does this circuit do anything?

I think I am failing to understand how a zener diode works. Please let me know what you believe will happen if I were to make this circuit.
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Voltage across Zener diode is higher than the Zener voltage

I have this circuit: Assuming that the knee current is 0.2 mA and that the Zener voltage at current 5 mA is 7V. I would like to find the voltage across the load. I am however confused with the ...
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Step by step explanation of voltage regulator

Let's consider this basic scheme of voltage regulator (here the reference): I wanted to verify that a sudden variation of the output voltage is compensated by the circuit. Suppose that the output ...
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TSM104W Voltage Reference

Hi I am trying to design with the TSM104W, which is a 4 package rail-to-rail OpAmps, with a built in voltage reference. This is the package pinout: I see that the four Op-Amps are supplied through ...
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Trying to understand how they got equation for Vzo

this might seem like an easy question but I'm still new to circuits and I'm trying to understand how they got the equation for voltage. They have the solution as 6.8=Vzo+5m(20), but when I looked at ...
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Relationship between Zener diode voltage and knee voltage in forward bias? Also the resistance in forward bias

Can somebody please help me establish a relationship between Zener diode voltage and knee voltage in forward bias? That is something where I could not find anywhere.
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How to calculate the power rating of zener diode for flyback protection?

I'm trying to calculate the power rating for the zener diode I'm using on my circuit for flyback protection. For example, if a flyback event occurs, the cathode of the zener diode is having a 30V ...
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Power zener with mosfet + zener

I have two solar panels in series giving ~106 volts when open circuit and around 4 Amps when loaded. My mppt controller could accept 150v on the input, but it blew up when the battery was ...

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