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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how to measure leakage current across a zener diode with a transimpedance op amp
I am trying to measure the leakage current of a SMF36CA zener diode. I am doing this with a transimpedance op amp (LMC6062IM/NOPB).
Attached is the circuit I am using. The amp and diode in the circuit ...
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Why is my output voltage of my 4-20[mA] to 0.8-4[V] converter saturated at 2.9V?
I built a 4-20[mA] to 0.8-4[V] converter using a HCNR201 optocoupler. The diagram I used was the shown in the datasheet:
I'm testing this circuit with a 0-5[V] to 4-20[mA] converter sweeping the ...
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The most minimalistic solar charge controller possible: will it work?
I want to build a solar panels device that can supply power to my doorbell, which is installed over a gate with no access to wires or power. The gate has a "bar" on top where I can install ...
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Choose the RLoad resistor for zener diode
I need to calculate the Rload resistor range for the operation in this case:
I know that many times to calculate the Rseries but now he is given,
how does my teacher expect me to calculate the RL?
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Zener diode wrong gate voltage regulation for battery reverse protection
I have the following circuit meant for reverse polarity battery protection.
The battery is a 2s li-ion (8.4 V to 7.0 V), but it could also be a 12 V max PSU.
I'm not sure what's wrong on the PMOS gate,...
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High voltage MOSFET linear regulator failure
I designed the circuit below for an FSAE electric vehicle, for which the rules require an HV-powered LED to be lit when the HV bus is above 60 V. In simulation, the circuit works very well.
In real ...
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Zener Diode for switching Mosfets with BQ25798
I'm looking on the datasheet of the BQ25798 (Buck Boost Lipo Charger) and was wondering which task the Zener Diode and the 294 Ohms Resistor has.
I had an idea that the resistor is maybe limiting the ...
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Zener diode as clamp in output of comparator not working
I'm trying to have the output of my comparator be either 0 or 5 V.
I'm using an LM311P comparator supplied with 24 V-0 V. At COL_EMIT, I'm using a Zener diode of 5V1 to impose 5.1 V as the maximum on ...
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5V, 50 Ω input single pulse signal to an FPGA
I have a 5 V, 50 Ω input single pulse signal (<1 ms pulse width) going into Trenz TE0711 (operating @3.3 V and 50 MHz clock). Since the input signal is too high of a voltage, I am trying to find a ...
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What is the purpose of the Zener diode in this relay coil circuit?
It is clear that the ordinary diode is the usual flyback diode that dissipates the energy stored in the coil while it is turned off, but what could be the purpose of the Zener diode?
I think the main ...
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I need a simple circuit to provide about a 2.5 second power-on delay to a 5 volt mini relay 6 volt DC supply using a RC/Zener to 2222 base lead
I've tried various circuits with the result that the 2222 transistor fires up the relay instantly ... The relay coil is 46 ohms I'm using 4 AA cells for 6volt DC supply, a rectifier diode to control ...
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Zener diode testing
I have been testing a Zener diode I have using following this video. One thing I noticed and could not understand is that the Zener starts conducting when it has not reached it breakdown voltage yet.
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Zener diodes back to back on audio XLR outputs
I'm trying to understand the purpose of these two Zener diodes in a single package (DZ2S180C) on an audio mixer circuit. I suppose it's to protect the circuit from voltage spikes possibly coming from ...
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How to calculate the base current of the transistors in this voltage regulator?
I arbitrarily chose the resistors value and tried calculating the base currents.
On Q5 base resistors I tried thevenin, but it didn't work. The values weren't the same as the simulation.
And in ...
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Is my Zener diode broken?
I test my Zener diode IV characteristic (reverse bias).
It is a 1N4728 3.3V Zener diode, but its exponential IV curve seems like a normal diode with lower I_sat(?)
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Can this analog input over-voltage protection using a Zener diode and FMMT718 transistors work?
I have a problem in my electronic board. When I connect the signal generator 10V with my PCB in the header which contains my overvoltage protection solution based on a Zener diode, some FMMT718 ...
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What should be the output and purpose of this section of an EV inverter circuit?
What should be the output or purpose of below circuit (which is a part of EV inverter circuit).
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Use of Zener diode
I was constructing the UC3843 on PSIM from scratch. The circuit diagram and the application note state that if the input voltage is greater than 34 V, the Zener diode does not allow the circuit to run....
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Zener diode identification - no marking codes
Can anyone help me identify the Zener diodes marked on the PCB as D11 and D13? It's for a GoldCut 2010A cutting plotter.
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12 V to 5 V reduction for bi-directional motor (DCC model train)
I am modifying some old DC model trains to be DCC (digital control with a decoder). The decoder puts out 12 VDC PWM to the motor, but obviously switches the polarity around to change train direction.
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LED supply 5-30 V - Zener diode?
I would like to make a circuit that will allow the 20 mA red LED to light up at an input voltage from 5 V. Input voltage will never exceed 30 V.
Should I use a Zener diode with a resistor? I saw some ...
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What is the role of D2 in the schematic diagram?
Can someone explain to me how this circuit works?
I know D3 is a flyback diode, and BSS138 is a FET which means a low voltage can drive the relay on or off.
What is the purpose of D2. Why use two ...
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Identifying SMD diodes
I have dismantled a circuit that controls hot water flow through a solenoid valve, driven by electronics using the PHASE-CUT method at 24 VAC, 10 W, controlled by a 0-10 VDC input.
I have discovered ...
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What current flows through a Zener diode that is in parallel with the gate of a MOSFET?
I was reviewing this circuit and I can't figure out how much current goes through the Zener diode. I understand that it is there to protect the MOSFET gate against high voltages but how much current ...
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Voltage rating of a Zener diode
How do we find the voltage rating of a Zener diode found alone by chance, when the only way to identify it is to inspect, test, and so on?
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3.6 V Zener diodes clamping at 2.3 V
I'm scratching my head on this one:
This is a basic unity gain follower. Max. ADC input is 3.3 V. However, on my prototype boards all OUTs maxed out at 2.3 V.
So I removed D1 and D2, and then the ...
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LTspice simulation: voltage clamp of capacitor
I have this circuit to simulate a voltage clamp of a capacitor string:
The zener diode has a breakdown voltage of 4.7 V.
I use step param for the parallel resistor of the cap.
Here are the results ...
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1N4728A Zener diode not giving the expected voltage
I've been trying to understand the proper usage of Zener diodes, but I've not been able to get the behaviour I expect based on my understanding.
For example, in the test circuit below I would expect ...
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Finding Vcc from Zener diode?
My apologies if this is a really simple question. I have very limited circuit knowledge.
I found this article (https://embedded-lab.com/blog/introducing-easy-pulse-a-diy-photoplethysmographic-sensor-...
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Is there a formula for the current leakage of a Zener diode?
I have this setup:
The problem with this setup is that when there is a 3.2 V voltage drop acriss the 160 Ω (vertical) resistor, then there's NOT a 3.2 V voltage drop across the Zener diode, in ...
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Can a Zener diode protect an input pin that is driving low?
I am trying to protect a +5V Digital Output pin from miswiring to +12V, using a Zener diode.
When I simulate a simple protection circuit, the zener clamps the voltage as expected:
However this ...
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Simple low-current voltage limiter in a solar battery charging circuit
I am trying to devise the simplest/cheapest possible circuit for using a small solar cell to maintain the charge on a single-cell lithium battery. The reason for low cost is that I need to build ...
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How to calculate the resistor values for the zener diode and the BJT base?
I try to convert ~12V signal from a car button (the input voltage can be from 10V to 14V) to a logic level signal for MCU, but the signal should to be inverted (1 = 0, 0 = 1).
Below is my schema, but ...
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RS485-Protection(signal (A-B) from input voltage (12v and 24v )using TVS diode
To protect RS485 signals differential (A/B) from power input (12 and 24 V), we can use TVS diodes.
TVS diode parameters:
There are many types of TVS diode in the market, designed for a specific ...
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Voltage regulator 78M05 supply line reverse biased Zener diodes
I have a technics graphic equalizer SH-D5000 and it keeps on frying reverse biased Zener diodes which are in series with the input of a 5 volt regulator. The supply line is 40 volts DC. What Zener ...
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13.75V (AC) Door bell ringing signal to Raspberry Pi GPIO - Am I on the right track of which components I need? (Beginner)
I'm in the making of a RaspberryPi doorbell. It will have to possibility to send events and receive actions/commands via a Telegram bot (already working). The approach is to connect it to the handheld ...
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Looking for replacement diode V6 88
I'm guessing this is either a Zener or TVS diode. All I can see is 'V6 88' i can't find any info anywhere about it. My ECU in my bus has cooked 2 of these, side by side, so I guess they need replacing ...
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Trouble identifying unknown component
Please help me to identify the component marked "SPWP". Even Google search is not giving any results and manufacturer logo is also not in list.
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Transistor based voltage regulator with normal diode
On another thread I was discussing about Power Supply for an equalizer that originally takes a 9VAC as input, then I found some interesting things on the input circuit of the equalizer that I did not ...
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Residual current in 5 V circuit [closed]
I am using a 3 V DC supply to light a 3 V LED.
I want to immediately stop the LED upon disconnecting power, but the LED stops after 2 seconds.
So how to stop the LED immediately? What size Zener diode ...
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How to interpret this Zener diode IV characteristic diagram?
I'm looking at the datasheet for the BZX55 Zener diode. The given Zener IV characteristic are in page 5, Figure 8 and 9, (one copied below):
I'm confused on what this is saying. I understand that ...
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Parameter missing to calculate the Zener diode maximum current
I want to operate this 3.3V 5W Zener diode without any heatsink at a maximum ambient temperature of 55°C, and I want to estimate the maximum current at 55°C.
Maximum junction temperature Tj is given ...
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Zener diode rating
The 1N5919B Zener diode datasheet gives the power rating as 3W. It drops 5.6V across i.e. its Zener voltage is given as 5.6V.
Power = V * I and in this case I would say Imax = Pmax / Vz --> Imax = ...
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Is it worth to build a discharge circuit for long storage of lithium-ion batteries?
I am making a battery powered system that might not be used for months. There will be an On-Off switch but I am planning to use a three position switch in order to discharge batteries to 3.9 V when it ...
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Is Zener Diode a good choice for DC voltage regulation for a buck converter? And how should I use it?
I have a buck converter that I want to use to step down the DC voltage from a UPS to 13V to power a CCTV set-up. The buck converter input is specified as 40V but the UPS output fluctuates to a max of ...
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MOSFET Vgs(max) and built-in Zener gate-source diodes
Some MOSFETs have a built-in ESD protection in the form of back-to-back Zener diodes between source and gate.
An example can be seen here.
DMG2302UK internal schematic
This particular MOSFET has a Vgs(...
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Why is a Zener diode's temperature coefficient ±0mV/K at approximately 6V?
I am familiar with Zener diodes and their parameters.
It's interesting to see the same temperature coefficient at approximately 6V across different manufacturers and different packages. See below ...
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ADS1115 differential overvoltage protection for three inputs and one reference input
I am trying to protect three separate inputs (A0, A1, and A2 with A3 as reference) of an ADC from an over-voltage of ±10V DC between any of the inputs or the reference (the reference is not grounded ...
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Reverse spike protection via MOSFET
M3 has |Vds| > 300V |Vgs| = 10V
Protecting the load from V1 = -300V 100ms spike:
Does this diagram, with carefully picked components, look like it will do the job ? Hw do I select R1, D2 and D3 ?
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Voltage reference circuit with op-amp and Zener diode
I am looking at the voltage reference circuit used in a source measurement unit, which is meant to be stable and precise:
The circuit above is said to be a 10V reference as described in the block ...
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