Questions tagged [diodes]
Diodes are semiconductor components made from a P-type (or metal in Schottky diodes) and N-type material (usually silicon, but germanium, selenium, and gallium arsenide can also be used), that allow current to flow in one direction only.
3,906
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Help in identifying an abnormal PCB found suspiciously [closed]
This is an odd PCB I found a while ago on the bedroom floor of my apartment next to my bed where my dongle for extra USB-3 ports was hanging off the bed. I have no relationship to this board, it's not ...
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identify these parts please 116R1 - in sot23-3 package 115Z1 - in sot23-3 package [closed]
help identify these parts
116R1 - in sot23-3 package
115Z1 - in sot23-3 package
have tried to identify but unsuccessful
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4
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Alternative to a single high spec'd diode
My series blocking needs to pass 8 A and I am wondering if I can use 4 diodes (rated 2 A each) instead of 8 A.
We have a cost constraint, hence we are looking for an alternative to replace a high spec'...
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I need diode for 24vdc ice cube relay. How do i select one? [closed]
I have a TruMeter APM process meter that can display Voltage, amperage or any other value in digital format using 0-to-10V or 4-20 mA signal, but can only use the internal switching contacts for ...
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Dehumidifier power supply [closed]
So my 5 band 1w 8.2 ohm resistor blew, 2 diodes and fuse. I replaced the fuse and the diodes and the resistor, but the resistor seems to be the only component blowing over and over. Could it be the IC ...
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1
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How do I find a transistor and diode equivalent to the ones in the photos below?
I'm looking for the two transistors in the photos below, but I can only find the partial numbering on sites like aliexpress.
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1
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Please help me identify a diode
Good day,
I can't seem to find any information about this diode/component. It measures 53.7 Ohms and only 25 mV on diode junction test. Would you please be able to help me identify what it is and ...
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Help identify part with marking code |ACG and VE
I have two similar 5-pin sots, one with marking |ACG and another one VE. They're probably tvs diodes but I can't be sure. I need part number for both of this.
I have searched through various smd ...
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Identify device marked `NY2`
Can anybody identify the component marked NY2 shown in the picture?
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Flyback Diode Question
I would like to have a quick review of my circuit diagram. I want to ensure my flyback diode is correct and I have a sufficient diode for my use case.
I am using a LiPo battery (4.2 V max / 3.7 V ...
4
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1
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Help Identify SMD Part Marking ATPJ
It's a 6-pin SOT with marking "|ATPJ".
My guess is it's SOT-363 but I'm not entirely sure.
Can you identify the actual part number for this.
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Proteus X-Y mode graph
I am trying to plot the I-V characteristic plot of diode. However when I am dc sweeping the DC voltage source and plot the Id probe it is actually giving me Id vs V1 plot. But I want Id in the y axis ...
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Should I be able to see light from a IR Led with my own eyes?
I know that infrared light should not be visible to the human eye.
I connected a diode and phototransistor from the encoder of an old printer and I can see a red dot. My worries are that the device is ...
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How does DS18B20 temperature sensor get the temperature?
I’m trying to understand how the DS18B20 temperature sensors works. Is there a way to know whether it uses a diode or thermistor to calculate the temperature? I couldn’t find anything on the data ...
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Can anyone solve this question using the "assumption" method?
I started with Vin<0 and assumed the 4 possible combinations of D1 and D2. For Vin<0, either D1 and D2 can be on or D1 is off and D2 is on. The book shows D1 off and D2 on as the correct answer, ...
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Is it normal to be able to tear off PCB components with bare hands? [closed]
I just ordered 5 boards from a popular Chinese PCB manufacturer and (for the first time ever w/ with this manufacturer) some SOD-323 diodes and their pads and adjacent tracks were peeled off out of ...
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1
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Estimation of when to prefer ultrafast silicon diodes over silicon Schottky diodes
When comparing "ultrafast" silicon diodes (those with usual recovery times given as either 50 or 75 ns) to silicon Schottky diodes at the same blocking voltage and average current rating, ...
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What is this diode marked IN4001 B4?
the information on the diode reads as either:
IN4001
B4
OR
1N4001
B4
I am trying to purchase a replacement diode and the only close matches I can find make no reference to the B4 element. Is this part ...
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1
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4
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Determining the ohmic value of a carbonized resistor in a flashlight circuit [closed]
this circuit is for a rechargeable flashlight. It charges the battery using a 220V power supply, after reducing the voltage. A capacitor and a resistor in this circuit are damaged. The capacity and ...
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For high power laser diode, how to determine relation between limit values of pulse duration, repetition rate, and energy?
For a work project I have a laser diode of 808 nm wavelength. It allows current of 190 A at which it gives 2400 W of optical power. According to data sheet, at this current the allowed repetition rate ...
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Output control with protection using MOSFETs for bench power supply
Recently I been making bench power supply powered with both barrel jack and USB-C with support up to 3A output.
I wanted to control output with ESP32 based MCU (3v3), it should be normally closed ...
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What is this SOIC-8 marked "BB REF / 02BU / 78GSY"?
I'm trying to identify an IC labeled BB REF / 02BU / 78GSY. It is an 8-pin SMD, in SOIC format.
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How does a push pull transistor switch?
I have some difficulties regarding this single supply diode biased push pull amplifier.
Every book and video out there says when one transistor is on the other will be off - just as simple as that. ...
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Motorcycle relay with series diode query
I would be really grateful for some advice on the following issue. A relay failed on my motorbike (2009 BMW XCountry) and I replaced it with standard relay. I have been experiencing parasitic drain ...
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Does an array of Peltier module need a diode between each module?
I have a bunch of Peltier module that I wish to connect in series/parallel and use them as a thermopile generator. However I was wondering if its necessary to attach a diode between each module (see ...
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1
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ORing of 2 batteries and reverse polarity protection
I am trying to find a solution for ORing of 2 Lithium batteries, that also provides reverse polarity protection. Single cells are used, so the voltage will range from about 3V to 4.2V. Also, the two ...
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2
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What is the purpose of this diode in the gate of a JFET
I am studying how the bypass circuit of the Tube Screamer pedal works. It is dependent on two JFET transistors that are used as switches. I am not great at understanding JFETs as switches, as I have ...
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How can the diode conduct in negative half cycle of AC signal in clamper circuit?
Could you kindly help me understand the clamper circuit. I watched a couple videos and I'm confused. My confusion is in positive clamper circuit. How can the diode conduct during the negative half ...
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Diagnosis and Replacement of 2N1101 transistor
I have a circuit board with 3 transistors on it, all of them are 2N1101. I'm trying to diagnose the problem with the board with the diode tester on my multimeter. I found 2 of the transistors have a ...
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Part number of this IC marking "R2. 8"
Can anyone please help me define the part number of this part marking "R2. 8" in the picture below?
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Trying to identify a vintage (1992) diode
I'd like to identify the vintage diode at position D15:
This diode is found on a PCB from a 1992 Mercedes 300D (W124) Convenience Control Unit (it controls the windows, sunroof, etc.). I don't think ...
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How to know what size diode to use for inductive spiking?
I am making a simple Zener flyback circuit for an inductor.
What current rating should the diodes be sized for? Could I use a 1 watt Zener diode because the voltage spike only lasts a few microseconds,...
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1
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The role of Q33 and the connection of pre-discharge circuit in the BMS circuit
I'm trying to understand the following circuit which is taken from the TI's TIDA-010216:
I don't understand the role of Q19, D29, D30 and Q33 in the circuit. According to this post, it seems that Q19,...
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Usage of two PSU in parallel for WiFi router using Schottky diodes
I have Wi-Fi router which is powered by AC adapter with nominal output 9 V, 0.6 A. Due to power outages I have bought USB DC-DC adapter 5 V ⇾ 9 V and power it from power bank/power station. Router ...
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Part Identification and Circuit clarification
i am trying to repair a laser driver circuit.
Apparently, it was connected to a lab power supply (the driver is rated 4-5,5V, 8A) and someone turned the knob, so it got way higher voltage.
I ...
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Flyback Diode Forward Voltage
Using this link as reference.
Question 1:
From my understanding, if the applied forward voltage across a diode is much greater than its rated forward voltage the diode will potentially fail.
Based on ...
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What is this symbol on the manual for a Yaskawa servo drive?
I'm attempting to wire a Yaskawa Sigma-V Series AC servo drive to a Rosetta CNC, and I came across this symbol, a triangle that has one line in, one line out, and what seems to be a return line ...
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1
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Chip Identification - TVS diodes
Can someone please confirm that these are bidirectional TVS diodes, I cannot find the datasheets for these anywhere, but they look to be them.
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About diode question solution
While solving the diode question, a point like this stuck in my head, I did the solution in this way, but I ask you to help the community
For X value; (I thought it should be found with a voltage ...
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a question about silicon diode
Which of the options is correct for a Si diode?
a) It conducts if the voltage applied to its anode is greater than that applied to its cathode
b) If the voltage applied to the cathode is greater than ...
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1
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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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How to Properly Select Resistors and Capacitors for a Voltage Reference Circuit with BJTs
I am working on a reference voltage circuit and I am having trouble when selecting the appropriate resistor and capacitor values. The circuit involves OP07 operational amplifiers and transistors (...
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Ideal diode in parallel with resistor and voltage source
Sorry if this appears to be a silly question, but it is a concept I am having trouble with.
I don't quite get how to arrive at this plot. The current from V1 as a function of V1.
If V1 > 0 then I ...
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Changing the Limits of the Graph When Trying to Model the Shockley Equation in MatLab Shifts the Position of the Curve [closed]
I have been trying to create a piecewise linear model of a diode through curve fitting. While trying to implement the code below, I ran into a strange bug that is causing my output curve to shift to ...
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DC-DC convertor-SEPIC architecture
I'm working on a SEPIC DC-DC convertor, in the reference design from Texas instrument there is MOSFECT which is derived by DR pin of the main controller (LM3488) as follows:
There is an diode (D4), ...
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Powering on a laser diode that exceeds PSU max current
I have a laser diode that I want to test (just seeing if it turns on). However, the threshold current is past the 10A that my bench power supply can supply, hence I can't generate any light. How can I ...
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