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

1
vote
1answer
36 views

Single input terminal for multiple voltage inputs

I am designing a board for which I want to have single input terminal for voltage. Board is microcontroller based(Atmega328) so the voltage coming to uC(Vcc on picture) should not exceed 5V. How I ...
0
votes
1answer
24 views

BZY97C47 zener diode datasheet questions

The BZY97C47 data sheet (I found no direct PDF link) confuses me on several points. I fail to find straight forward information about the maximum allowed forward current from the data sheet. Also, ...
-2
votes
0answers
45 views

Zener diode design

Design DC voltage regulator for 6V output. Given data are Vz= 6V at Iz = 20mA, Izk=2mA, Pzmax=500mW and rz=20ohm. The input voltage varies between 9.6V to 14.4V DC.Find the voltage regulation factor ...
1
vote
2answers
74 views

Are my zener concepts wrong?

If a battery of 60v with internal resistnace 4kohm (in series) is connected to a zener diode of v_z=10v in parallel and a load resistance of 2kohm in parallel too, what will be the currents in ...
1
vote
1answer
38 views

Passive ringing on PCB causing noise

I have a PCB that is exposed to a sharp inductive-voltage collapse, around 100V/100nsec. The voltage collapse happens when the current through a transorb reaches zero. When this happens, the board and ...
2
votes
3answers
137 views

Virtual GND resistor dividor vs zener diode

I was having a discussion with someone about using a virtual gnd for an opamp circuit. One way to provide the VCC/2 voltage is with a voltage divider made of two precision resistors (and a capacitor ...
1
vote
1answer
78 views

AVR USB to Serial Converter; Quick Question

I have a TI86 calculator that I've had for over 7 years now. Well I'm letting a lady friend on mine borrow it, and I was going to load it up with some apps for her. And the tradeoff is happening this ...
0
votes
1answer
99 views

Reduce power supply voltage

I'm trying to build the power supply described here. R1: 1K8 1/4W Resistor C1,C2: 4700µF 25V Electrolytic Capacitors D1: Diode bridge 100 to 400V, 1.5 to 4A D2: LED Any type ...
2
votes
3answers
149 views

Lower Voltage With A Zener Diode

I am trying to lower the voltage from a 9V battery to 5V for use on an Arduino pin. I bought a 5.1V zener diode from RadioShack. Will this do what I want? Do I have to lower the amps as well? It looks ...
1
vote
3answers
276 views

Please explain this circuit (CNY70, Zener diode) [closed]

I am trying to build a new (Arduino based) controller for a machine that contains a circuit that uses a CNY70 to detect RPMs in a motor. The circuit takes a 5V input and I accidentally gave it 24 ...
2
votes
2answers
64 views

What are the electronics components that have characteristics like Neon Lamp?

Neon lamps have higher breakdown voltage than its operating voltage. When brokendown, it acts like a zener at its operating voltage.
0
votes
2answers
71 views

Alternative to V divider for high currents

I am looking for suggestions as to how to supply power to a gate drive optocoupler i am using. The supply being used is a 25V (rms) ac supply and intend to supply 10V DC at around 500mA+ from my ...
0
votes
1answer
49 views

Voltage regulation vs relative voltage tresholds?

There is a part of my circuit that uses resistance to output a voltage, in which is compared to a voltage threshold to output a digital signal. However +Vcc can vary and any voltages too far from 5V ...
5
votes
2answers
190 views

Zener Diode Selection for Relay

I am using a Zener diode along with a flyback diode with a relay in order to speed it up a bit. This works very well but I am currently using a rather over-sized zener from the inventory. For ...
0
votes
1answer
117 views

Why use two power sources when designing a voltage regulator using a zener diode

I am currently designing a voltage regulator using a 5V zener diode. I am wondering why some people choose to use two power sources instead of one, what would be the benefits of this ? the circuit ...
0
votes
1answer
117 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 ...
1
vote
3answers
151 views

How a zener and a schottky diodes protect laser diode?

I purchased a strain relief wire SR9C which has a small protection circuit for a laser diode. It says to contain a zener and a schottky diodes which protect the laser diode from ESD. By looking at the ...
0
votes
4answers
109 views

Running 3,6V MCU on full 4,25V Li-ion battery

How can I run 3,6V MCU on a fully loaded 4,25V Li-ion battery? Normally the battery would be 3,6V, but on fully charged it is 4,2V, it would kill the microcontroller. Load is 10mA, minimum voltage is ...
5
votes
1answer
418 views

LED as Zener: is this a good way to lower the BOM cost?

I had an old AM radio board designed to operate with a 3V CR2032 coin cell. I want to revitalize this old junk with as few parts as possible and convert it into a USB-powered AM radio with a built-in ...
0
votes
1answer
100 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
46 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 ...
7
votes
3answers
263 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
290 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
208 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
102 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
109 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
94 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
36 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
144 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
106 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
126 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
96 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
379 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
104 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
305 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
139 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
94 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
245 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
42 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
292 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
511 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
623 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
2k 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
44 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
573 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
236 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
736 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
112 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
366 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 ...