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. ...

learn more… | top users | synonyms

0
votes
1answer
56 views

Protecting resistor value for zener diode in parallel with load

I want to select x as resistance for the protecting resistor (upper). The zener diode can hold up to 4A If I was guaranteed to have current through zener lower than 4A, I could consider its ...
0
votes
2answers
35 views

Relationship between Zener voltage and current?

What's the relationship between the current flowing through the Zener Diode? I simulated the following for various values of R, and the voltage drops quite a bit with small currents. The 1N750 has a ...
6
votes
3answers
174 views

Protecting microcontroller from inductive loads

I'm working on a project where I will be controlling a variety of loads (relay, solenoid, motor) from an Arduino and I'd like to make sure I build in enough protection for the microcontroller and ...
3
votes
4answers
225 views

Why I=(V(in)-V(out))/R in zener resistor circuit

I am a hobbyist electronics student who try to study "The art of electronics" book. I am having trouble understanding below passage from the book? I am having trouble following what is going on ...
1
vote
2answers
140 views

How does a zener protect my microcontroller?

I'm connecting a 12V inductive limit switch for my 3d printer to a RAMPS controller (Arduino-based printer controller). The RAMPS board operates at 5V, and connecting the 12V signal from the limit ...
0
votes
0answers
79 views

Why use a zener diode when connecting a OLED display?

So I have this full color one inch OLED display from US Micro Products which has the driver SEPS114A. I am planning to connect it to an Arduino board using SPI, and the recommended schematics from ...
0
votes
0answers
81 views

Can a zener diode be used to slow down a fan?

I often use a resistor to slow down a fan in older PC's, because these old computers are too noisy. Can a zener diode be also used to slow down a fan in a PC? As far as I know these small fans are ...
0
votes
3answers
60 views

What is the Q-point of the zener diode?

Is the Q-point f the zener diode in figure equal to its breakdown voltage of 4 V ?
0
votes
0answers
28 views

Limit amplitude and isolate impedance of a clock signal, without introducing noise

I am trying to drive the clock of a sequential logic circuit from a high-impedance input that receives a clock-like signal of somewhat variable nature from an external source. Input in practice may ...
1
vote
2answers
75 views

What is the purpose of a Zener diode added to the output of a SMPS?

I studied circuit diagrams of some computer ATX power supplies. Some of them have got a Zener diode at the very end of 5V stand by line. The picture shows endpoint of the circuit - the SMPS is on ...
0
votes
1answer
94 views

Zener diodes in series

Hello, In this problem, i am not able to understand how I2 is getting replaced by I01. More over, will these zener diodes become ON as the applied voltage is less than Vz? Thanks in advance.
0
votes
2answers
68 views

Zener Diode Minimum Input Voltage

My question is with regard to establishing regulation using values taken off the characteristic curve. I have \$I_{kn}\$ = 1.8mA and \$V_z\$ = -8.2V. How can I determine the minimum input voltage for ...
0
votes
1answer
57 views

Use Zener diode to control an LED array?

I am trying to use an LED array to indicate a voltage level. For example, if the voltage is 3V, then 1 LED is lightened up. If 4V, 2 are lightened up. If 5V, 3 are lightened up, etc.. My previous ...
5
votes
1answer
314 views

Zener diode circuit

When I tried to find current flowing through 1.2k ohm resistor, I am finding 8.33 mA but there comes the problem: I am finding the current through the 1k ohm resistor is 6 mA. What am I doing wrong? ...
0
votes
1answer
81 views

Zener diodes comparison 12V vs 6V2

12V zener diode has the same series as 6V2. It also has same wattage of 500 watt but VZ of 12V. Will it handle the same maximum current IZT as the 6V2? Any proof?
2
votes
4answers
166 views

Anti-wind up scheme in the implementation of PID controller

I want to implement designed PID controller. But I am facing the problem of how to limit the saturation limit in both positive and negative direction? I tried using zener diode, but I would like to ...
0
votes
0answers
81 views

Simplest signal level/clip LED indicator?

I was looking to modify a circuit that would take a signal from a guitar, impedance-match, amplify and bias it so that it would be readable by the ADC of a micro-controller, effectively based off this ...
0
votes
0answers
68 views

Zener Diode exercise ,are my solutions correct?

We have \$V_z = 6.8\$ V \$I_z = 5\$ mA \$r_z = 20\$ Ω \$I_{zk} = 0.2\$ mA \$R = 200\$ Ω \$V_s = 9\$ V a) Find the output voltage when we have the input voltage \$V_s\$ with the nominal value of ...
2
votes
2answers
171 views

How does R5 bias the zener in this SMPS circuit?

In the description for the circuit below from this data sheet for TNY268 off-line SMPS switcher, it says R5 is used to ensure that the Zener diode is biased at its test current and R6 centers ...
1
vote
0answers
33 views

How do I find the maximum surge current of a zener from the given thermal resistance curves?

I'm driving a MOSFET, and I want to protect its gate with a zener diode. Here is the MOSFET data: ...
1
vote
2answers
207 views

Reducing Ripple in the Zener Regulator

In the Art of Electronics (Horowitz & Hill) the following circuit is given as a solution to reduce ripple current caused be variations in input voltage (pg. \$ 69 \$): "An alternative method ...
0
votes
3answers
302 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 ...
5
votes
5answers
2k views

Why are there so many resistors in a typical schematic?

I know that some resistors cause pull-up or pull-down or work as a voltage divider and/or current divider. But sometimes I cannot understand their function in some simple circuits: Take this motor ...
-2
votes
3answers
365 views

A series resistor behind a reverse biased zener diode

simulate this circuit – Schematic created using CircuitLab If the Zener is rated at 4V, and the resistors R1 R2 are both 300ohm, may I know what is the value for Vout? I know this is a ...
0
votes
4answers
752 views

Zener + MOSFET overvoltage protection

I need a simple circuit to protect my device from overvoltage (more than 13V). Typical working DC input voltage is 7-12V. Can I use this circuit: Will it work? UPD. OK, it will not. I was too ...
1
vote
1answer
41 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 ...
2
votes
1answer
366 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 ...
1
vote
2answers
123 views

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: ...
0
votes
1answer
440 views

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)?
2
votes
3answers
107 views

Accurate -2V reference

I have an old Keithley 175A multimeter that has been suffering from a bit of drift lately. Internally it uses a 6.35V zener and a couple of resistors to create a -2V reference, but the zener is ...
0
votes
2answers
256 views

Using a Zener for reference voltage

I want to use a 9.1V Zener diode for a ref voltage into a op amp comparator so that when the battery voltage (11-12V DC) drops below 9.5V DC it will cut the supply to the circuit via a P-channel ...
-3
votes
1answer
92 views

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 ...
1
vote
2answers
369 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 ...
1
vote
2answers
156 views

Zener diode BZX55C3V3 does not behave as Zener diode

I have bought a couple of BZX55C3V3 diodes to protect the ADC inputs of the microconroller but I noticed they all behave strange (and each one in a different way). This is a ST 3V3 diode ...
1
vote
1answer
72 views

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 ...
0
votes
4answers
846 views

Zener diode as voltage regulator

I've been trying to make a voltage regulator using a zener diode. I used the BZX79 3.3V Zener diode. I connected the diode as the following: Data Sheet. I assumed that as as most of them it ...
2
votes
1answer
124 views

How to decipher zener diode encoding?

I'm new to electronics and I'm trying to reverse engineer the circuit board in an R/C car. I've come across a diode and it is labelled... C3V3 5T 1) I assume ...
2
votes
1answer
142 views

Can a Zener diode be used in place of a Schottky?

I want to use a LM226677 Voltage reagulator to achieve a step-down converter from 12V to 10V. However, in a Schottky diode is used reversely polarized at the output of the LM22677, and the datasheet ...
1
vote
1answer
158 views

What is purpose of zener diodes in this circuit?

I am reading the I2C tutorial: https://learn.sparkfun.com/tutorials/i2c/all Why wouldn't it work without the zener diodes? What functionality are they adding? They are just there to keep the voltage ...
0
votes
2answers
185 views

Zener Diode - Vz0

Theoretically, what is the importance of Vz0 in the following figure. When modeling the zener diode, why is Vz0 used over the diode's given Vz? For modeling, I was given the formula Vz = Vz0 + ...
3
votes
1answer
239 views

Using a Zener to protect devices from solar overvoltage

I am making some pretty crude devices that are directly powered from solar panels. The instability is not an issue, but I want to avoid over-voltage. I am using two 100W panels in series and want to ...
1
vote
1answer
134 views

DIODE as capacitor?

How does Diode act like a capacitor when voltage across diode is less than forward voltage spec. Basically when diode is turned off? What is its usual capacitance when diode (zener) is turned off.
4
votes
3answers
711 views

Why do we need many complex voltage references when a zener can do the job

There is a huge variety of Zeners that exist. They have varying breakdown pd among other things. Why then do we need voltage references that are more complex and made up of many components?
1
vote
1answer
128 views

Use voltage regulator instead of zener to protect GPIO

I've read several articles about protecting 3.3v GPIOs from unregulated over voltage, all of which involve using a zener diode, a diode for reverse protection and resistors in some fashion. example 1 ...
1
vote
2answers
81 views

Surge suppression for electric motor

I have a 4.2W 12V electric water pump connected in series with a water float switch as a sump pump, powered by a 1A 12V DC power brick. The switch has a maximum switching voltage rating of 100V. ...
2
votes
2answers
134 views

Reducing voltage for solid state relay

I have a solid state relay which wants a 1.25-2.5V "activation" input, but my output from the micro controller is 5V. Is it possible to use a zener diode for this? Or do I need a buck converter? I ...
2
votes
5answers
498 views

Why does the voltage of a zener diode match the voltage at Vout?

In this circuit, if: Vin = 9V Vz = 5V I understand that Vout will be 5V. Does that have to do with Kirchhoff's Voltage Law? How does the zener diode, if it drops 5V to ground, cause Vout to also ...
1
vote
1answer
65 views

Low current input source - current limiting resistor for z-diode needed?

I have a very low current input source (tiny solar cells) with a maximum short circuit current of 80µA which are loading a supercapacitor (1F/5.5V). To protect the supercapacitor from damage I added a ...
4
votes
2answers
607 views

MOSFET controlled by optocoupler using Arduino

I have a question about using an Arduino to control a MOSFET with optocoupler. The question is, the supply voltage may vary from 5 to 36 Volts. For example, sometimes I will use a 5V switching ...
0
votes
5answers
827 views

Using a Zener diode to ease a voltage regulator

I was reading a tutorial on how to hook up a zener diode to ease a voltage regulator. Here if you follow this link, as one can see the zener diode is dropping some amount of voltage to ease a voltage ...