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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6
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1answer
7k views

Zener effect and Avalanche effect

I was wondering whether there is a difference between Zener effect and Avalanche effect? How do they differ?
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Tips for Analyzing Circuit with Transistors

Below is a circuit from a homework problem where I am asked to find the operating points of the three transistors. What I need help with is calculating the base currents for the transistors labeled T2 ...
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570 views

Zener Diode Circuit Sees Voltage without source applied

I have a circuit into an optical isolator which is used to detect the status of a contact in the field. Zener diodes are used in series to drop the voltage to the optical isolator as well as as ...
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v-usb, zener diodes and circuit

I've toying with V-USB for a few days and got a circuit working in a breadboard with a Attiny85 and 3.6 Zener diodes. However, when I tried to get it done in a stripboard, it doesn't work. Assuming ...
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How to decide between a TVS or Zener diode for overvoltage protection?

I'll leave my specific circuit out of this for a more broad question: What criteria does one use when deciding whether to use a Zener diode or a transient voltage suppressor, for overvoltage ...
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do power amps need regulated power supply

Does a power amplifier needs a voltage regulator since it needs to draw current around 2 A depending on the wattage and speaker impedance. If we try to use a zener regulator, notice that a zener diode'...
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Zener diode forward voltage

I'm trying to learn how Zener diodes work and I think I get the overall concept (regulating voltage to the zener voltage level), but there's one thing I don't understand. I'm looking at this diode ...
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636 views

Zener Diode three terminal application

I am looking for a three terminal zener diode that can handle at least 125V (DC). Please post links to where I can check out a spec sheet of this component, if it exists.
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Designing a power supply (zener) to achieve steady 6V (\$\pm\$ 0.01)

UPDATE: My target is to obtain 6V as the voltage output. As you can see, it is 5.94 V. I've tried adjusting my variables, yet it varies from 5.6 to 5.94V, never having reached 6V. What would be the ...
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Using back to back zener diodes to clip voltage spikes in bipolar stepper motor

I have a stepper motor driven by an Allegro A4983 stepper driver chip and in some cases the motor can be back driven even while being powered up. This leads to blown motor driver chips. Would I be ...
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Measuring Power Amplifier with Sound Card

I'd like to measure the frequency response of my power amplifier, while it is connected to a loudspeaker. The power amplifier outputs at +- 50V, and I think the maximum input of the sound card is ...
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Flyback diodes issues and pull-in & hold current issues in this Relay circuit

Although this may be a basic question but I'm still struggling with it. In this schematic, two zener diodes D1 and D2 are connected back-to back across relay coil L1. The BVds = -30V for Q1. Can I use ...
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How to sharpen blue LED voltage-to-current knee at 3.0 V?

I want to use blue LED as simple 3.0V nominal vs brownout indicator. It will be mounted on tiny proto board and will be plugged into rails or other various parts of breadboard. I want to make same ...
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Differential resistance for a zener

I'm reading the BZX79 datasheet. On page 4 it lists differential resistance at 1mA and 5mA. For instance for the 3V version differential resistance is typical 325\$\Omega\$ at 1mA. Would that mean ...
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How do I use a clipping Zener at the input of an Opamp inverting amplifier?

I have a \$ V_{in} \$ signal for which I cannot guaranty that it would have an upper limit. I want to clip this input signal to a limit (e.g.; 8.2V) with a circuit like above. Is this circuit alright?...
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Is it possible to create a zener based spike filter?

I am analyzing this circuit of an ECU of an automobile and I found it's difficult to understand it's LM7805 was protected from spikes. You could find that 7805 configuration block in the right bottom ...
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Selecting correct zener diode

Hi I'm trying to build a PSU based on a design which has it's maximum input voltage 15v. However mine is rectified from 200VA 24Vrms centre tapped transformer. I need to use a zener diode to ensure ...
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What happens after a zener diode breaks down?

I've strapped a 6V zener diode across the 5V/GND rails of my circuit, and I want to know what will happen if my supply were to somehow fail pass 12V straight to the rest of my board. The zener will ...
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When/why would you use a Zener diode as a flywheel diode (on the coil of a relay)?

I have just been cogitating on the tutorial at http://www.electronics-tutorials.ws/io/io_5.html, and in the discussion of flywheel diodes it includes this sentence without further elaboration: As ...
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Zener Diode for Minimum Voltage Regulator

I forgot the name of it, but I remember one post where it said that you can use a zener diode as a "minimum voltage regulator". I don't think I used the right term for it, but here's what I'm doing. I'...
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What happens after a diode is used in breakdown region?

If a diode is operated in breakdown region and if it is used again will it lose its characteristics or work normally?
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2answers
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Is there such a thing as a Schottky zener?

I was thinking about this when I was looking for over- and undershoot protection. If you use a zener you can clip the overshoot at a defined level (ignoring the slowness of the zener), but the ...
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Zener diode in series?

Is it OK to use a zener diode in series? Normally I see them across the output of a power source to limit the voltage to the value of the zener. Putting it in series instead should reduce the ...
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2answers
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Zener diodes in high frequencies

Why don't they use zener diodes in high frequencies?
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How does a zener diode and a resistor regulate voltage?

I'm having trouble understanding the simple voltage regulator that can be built using a zener diode (from section 2.04 in the Art of Electronics). I know that it would be better to use amplifiers, et ...
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Does the TL431 have a “dropout voltage” per se?

I want to get a stable 3V reference from a +3.3V ±5% supply (so it can go as low as 3.135V and as high as 3.465V.) I know the TL431 is a shunt/zener regulator, so doesn't really have a dropout ...
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Electronic circuit switch for arduino

Is there anything I can use to replace this circuit? Its a very simple electronic switch circuit, (transistor+zener diode+resistor) The circuit is connect to a remote control, the remote control is ...
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At what current and voltage do typical resistors explode?

I don't have an explosion chamber, so I cannot test critical values. If you explode resistors with too high current-voltage combination, does it damage your equipment, such as multimeter and DC-...
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786 views

LM335 doesn't seem to work

I'm relatively new to electronics, and I'm trying to make a thermometer using a LM335 temperature sensor. By reading the datasheet I thought it was simple, connect up 5V to a resister, then to the V+, ...
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Non-isolated input conditioning for a crude switch

I'm trying to build something Arduino-based which can (among other things) detect when a user touches two specific fingers together. The best idea I can come up with is to have a wire on each finger ...