Questions tagged [zener]
Zener is 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.
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Zener instead of resistor divider on dc-dc converter feedback pin
This dc-dc converter steps up voltage from 3.1V to 7.5V. I'm curious about the unusual D2 zener + R3 resistor to set the output voltage, instead of the traditional resistor based voltage divider. I ...
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Will this over-voltage protection circuit work?
I am designing a PCBA that is powered from an AC adapter supplying + 19 VDC to the circuit. I want to add a protection against over-voltage, let's say up until + 24 VDC. I came up with the following ...
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Zener behaving strangely
I have recently put together a trivial low-voltage interlock circuit to prevent over-discharge of a 9v battery pack.
I use a Potential divider of 1600 / 5600 ohm to produce 4.7v when Vcc is 7.2.
I ...
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Identify Zener Diode with label of SF on an Antminer S21 hashboard
I have the following Zener Diode I need to replace, but I'm not sure how to identify it as there are 100s of diodes out there. The only marking I see is SF. How does one go about identifying this ...
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Jump on varistor I/V curve when "passing" through max. leakage current region to max. clamping voltage region?
I'm taking a course on semiconductor physics and another on something like "usage of electronic devices". On both I've come across the I/V curve on a varistor, this is:
I cannot find the ...
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Function of R6 in this voltage reference circuit
I've seen the following precision voltage reference circuit in schematic diagrams of several vintage instruments:
I understand how this circuit works in general: it is basically two constant current ...
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Zener MOSFET Voltage Limiter
I need an input protection for a DC-DC converter in a 24V automotive system environment.
The DC-DC is capable to accept 50V input but I need some sort of protection against load dump pulses which can ...
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Current limit resistor calculation zener diode
I designed an overvoltage protection circuit. My input voltage is 90V, and I need overvoltage protection at 90V. However, I used a 91V zener diode in my circuit. I have a problem calculating the ...
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How does a "regulating" source follower work?
Can someone explain to me how this circuit works?
The output voltage is ~2.4V. The zener diode breakdown is 4.7V.
From what I can see the OUT is simply
Vgate - Vgs = 4.33V - 1.85V = 2.48V.
Is this ...
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Why do I get 9V while the figure in the datasheet says I should get ~4V?
How do I get ~4V from Figure 9.1 below, when I simulate it I get around 9V. Am I doing something wrong?
The source of the original schematic "Figure 9-1" below is the Texas Instruments ...
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Am I using the Zener Diode Correctly?
I am building a custom atmeta328 board that I want to make sure handles the bootloader properly. I have DTR from my FTDI chip going through a .1uF capacitor to the Reset pin on the MCU. I also have ...
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Solid state relay switch circuit with Omron G3MB-202P
could somebody explain the use of the Zener diode and capacitor in the schematic of a switch utilizing an Omron G3MB-202P?
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Understanding this constant power laser driver circuit
I am trying to reverse engineer a constant power laser driver. Unlike constant current drivers, these use an integrated photodiode which monitors the laser diode output. The photodiode current feeds ...
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Calculate resistor value in Zener clipper circuit
I'm trying to build a circuit which drives one of two LEDs from a variable voltage power supply, which can range between -15 to +15 volts. I'd like the LED to hit maximum brightness as early as ...
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What is the quiescent current in a current limiting voltage regulator circuit?
Is the quiescent current simply the current drawn by Q1 and Rin when no load is connected to the output? How would this differ from the supply current?
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