Questions tagged [optoelectronics]
Components, circuits, or systems that convert between electrical and optical (light) energy.
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Help modifying this circuit please [closed]
This is the circuit
https://www.instructables.com/How-to-sense-220-V/
I can't find this phototransistor https://pdf1.alldatasheet.com/datasheet-pdf/view/45410/SIEMENS/LPT80A.html
But I can get this ...
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1
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How to drive this specific laser
I've done just a circuit to drive an old laser and it was like this one:
I was wondering if it could be suitable for driving the laser whose datasheet is reported below.
I have these requirements:
...
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Measuring low lux with ambient photodiode
For my application, I need to detect two light levels: pitch black (close to 0 lux) and a low ambient light level of about 0.1 lux (or higher). It seemed like the BH1680FVC ambient light sensor was a ...
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How to choose a phototransistor or photodiode?
I've found a photoresistor (yes, resistor, probably 30 years
old) in my scrap box, attached it to an ATtiny as ambient light
sensor, with a 100kΩ resistor as voltage divider towards +5V.
On power on, ...
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2
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53
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BT136 TRIAC waveform
I am using a TRIAC to switch an AC signal
(a typical example is shown in question Triac Switch Circuit using MOC3021 and BT136).
When a BT136 TRIAC is used to switch a pure sinewave signal, I want to ...
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2
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906
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How can we explain this strange phenomenon with an optocoupler switching?
Two optocouplers are connected according to the circuit below. The input voltage across the first optocoupler is a true square wave (3.3 V amplitude). The first optocoupler is an open collector output ...
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DVD burner laser identification
I just disassembled the DVD writer from a laptop and scavenged some parts. Around where the laser and mirrors and opto stuff are packed together, I extracted these parts.
Which one is the laser diode ...
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Does this two opto-isolators circuit versions work the same way?
I'm doing a circuit to control a 10W Led driver by an MCU, and I need both circuits isolated from each other.
So I need one pin from the MCU to control the led brightess by PWM (Arduino normal PWM ...
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3
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What does the VCC pin do in this Optocoupler?
I have this optocoupler, and I am trying to figure out how it works.
What is the VCC pin supposed to do? How does it supply current to the gate pin of the transistor?
https://www.digikey.com/en/...
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Using a LED as a debug serial port
I want to add a debug serial output port to a device that's sealed in epoxy. I plan to use one of three existing 3mm LEDs (red 617nm, green 568nm, or yellow 588nm), ±30° angle, that emerge from the ...
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If composite transparent materials thermal and electrical conductivity can be adjusted t what would be benefit?
Will it be provided less thermal and electrical gradient to support less dissipative system development for opto-electronics and related technologies?
For thermoelectric design how it cold be ...
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Is it possible to control the frequency of light?
I mean, controlling directly in the source, not filtering the light or arranging density of the medium. For example, brightness can be controlled by current or voltage directly. However, when I came ...
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Can anyone identify this chip which I think to be an optocoupler?
I'm trying to troubleshoot a Renishaw H-2000-5062-07-A optical receiver for a tool piece used in a milling machine. It has several of these 8-SOIC(?) parts and I very much suspect that they are ...
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How to track, measure, manipulate and/or synchronize the phases of trapped ion qubits [closed]
I am working on a simulation of the Honeywell trapped ion quantum computer. The papers say that it tracks the phases of the qubits using "opto-electronics" but it doesn't give any detail.
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Looking for 5mm discrete multi color LED [closed]
I want to make an electronic version of the Master Mind game as a hobby project. The challenge at the moment is to find right type of LEDs for the job. Below you ...
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Why are low band gap semiconductors (like silicon) not ideal for most solar cells? Are their atoms ionized by higher-energy photons?
Most sources on the web say that 1.3 eV or 1.4 eV is 'ideal' for most solar cells...
What happens to lower-gap, gapless or overlap materials (conductors)? Are they ionized, rather than sending their ...
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How to know which opto-coupler is suitable for high current application?
I would like a suitable opto-coupler to use as isolation from a 12V and around 30A current and another for 5V and around 30A. Are there any good opto-couplers for those ratings?
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SSR for Attiny85 using Optocoupler and Triac
Looking for some advice, I am trying to create an onboard SSR to control the switching of a 120VAC load (heater/lighting), with an operating power of around 1500W max. I chose the following parts and ...
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3
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671
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How to know the minimum LED current of an optocoupler?
I am going to need to use an optocoupler to isolate two circuits in two situations. In both situations, a MCU GPIO will be driving the LED of the optocoupler to send a signal on the other end.
I am ...
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What is wrong/missing from the process subsystem? [closed]
My teacher told me to reconsider the process subsystem but I'm not sure what is really missing from it.
background story: when a guy is standing on the porch, the LED lights up
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What is the purpose of using an analog optocoupler?
What's the purpose of using an analog optocoupler in this circuit? Why not a digital one?
An industrial battery charger. Normal operating voltage to monitor ranges from 120 V (Battery low) to 180 V (...
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2
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163
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Amplifying a small signal from a phototransistor
I am building an amplifier for a phototransistor. It works well under normal lighting conditions.
In my application, the light is very dim and barely produce any readable output.
I tried to increase ...
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What is this component ? Negative tiny LCD glass?
I disassembled a ceiling projector clock to find out how it achieves its projection. I found a very small screen (or glass, see image) backlit by an LED.
To build some projecting stuff, I would like ...
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1k
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How do I simulate a short/open circuit in LTSpice?
I am trying to simulate open/short conditions for testing an optoisolator circuit I'm building.
Essentially, I need to simulate SHORT and OPEN in order to verify that what I'm designing will output ...
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1
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Opto-Isolator FODM 8071 switching noise at output Issue
I am working with Logic Gate Output Optocoupler. I have tried removing 15pF capacitor but it didn't made any difference.
On output port it is generating noise
Any help would be appreciated..!
Thanks ...
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How does this optocoupled smoke sensor circuit work? [closed]
This is an optocoupler module consisting of an infrared LED coupled to a phototransistor as smoke sensor.
I got this circuit from this site.
According to T.K. Hareendran says:
For optimum ...
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7
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Is it possible to generate light with an antenna?
An antenna (e.g. a dipole) is able to radiate at a certain frequency thanks to the EM field generated by a current provided by a signal generator at such a frequency.
So, for instance:
Voltage source ...
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6
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Why do we have a limited bandwidth in electronics?
I've been looking around a bit on optical communications and it is said that the main advantage in using optical communications, namely optical fibers, lies in the gigantic bandwidth available, when ...
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AQW610EAH-PhotoMos Relay
Can we apply voltage across 1 and 2 pins to control normally closed (N.C) and to pins 3 and 4 for normally open (N.O) at the same time in AQW610EAH ICs (pin diagram of that IC above)? Or only one N.C ...
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Can I use 1 optocoupler to drive 4 MOSFETs?
I've this circuit and works correctly, now I need to control 4 MOSFET instead of 2, is the second schematic correctly?
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97
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Adjusting Voltage regulator with PWMed optocoupler
I have LD1084V adjustable voltage regulator powering servo and want to control its output from MCU. Optocoupler should behave as variable resistor so my thinking was :
I am mainly concerned with gray ...
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1
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Opto-isolator/ optocoupler for electric isolation in IC design
I came across while reading the opto-isolator technique used for electric isolation in embedded systems/ Integrated Circuits design that " Opto-isolator is not recommended for electric isolation ...
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Help using an FOD3182 OptoCoupler
So this is the Optocoupler I will be using:
https://html.alldatasheet.com/html-pdf/505064/FAIRCHILD/FOD3182/978/2/FOD3182.html
My question is with the schematic of the data-sheet. Using Ni-multisim I ...
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263
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How can I test a TLP582 optocoupler?
Have few of these components (TLP582) and I need to design a test circuit to test its functionality.
Datasheet of TLP582
I have no idea how to make a circuit for this.
What should I be testing in an ...
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Driving a 14-pin with DFB laser using D2570H
For our project, we would like to use the D2570 DFB laser from Agere system since it has a built-in photodiode with a TEC sensor, thermistor and a bias-tee embedded in an 'all-in-one' package.
However,...
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392
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Circuit to replace a relay
I want to make a simple ladder circuit to control the on and off of a light bulb using 2 switches, but I am going to manipulate one of the switches by means of a microcontroller, and also I don't want ...
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1
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76
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Understanding peak repetitive surge current
I have moc3021 optocouplers. The data sheet says it has a peak repetitive surge current rating of 1 amp, 120 pps. I was hoping to use a microcontroller to control 24V .800A AC with this optocoupler. ...
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Best way to AND all connected inputs to one output
I have an CNC router with 7 x SN04-NPN sensors connected in parallel with one control board input. The problem is obvious, i got random false endstop triggers due leaking of SN04. I know i should have ...
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3
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Position of current limiting resistor
I am designing a digital output circuit.
I got confused about the position of the current limiting resistor of the transistor.
I would like know where it should be. (After or before the pull up ...
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1
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How to compare OLED and LCD brightness
I am trying to build a night clock projector, inspired by this project: https://microengineer.eu/2018/05/01/diy-night-clock-projector/
As I am more a computer scientist than an electrical engineer, I ...
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Ham Transceiver to computer Interface design question
I am building a Ham transceiver to computer interface, which has the RS232 port controlling the PTT on the radio. The circuit currently calls out for a 1.2K resistor in series with the RTS line and ...
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Photon lifetime in an optical cavity
Hi I have the following problem and data for an optical cavity.
Length \$ L=100 \mu m\$
Reflectivity \$R=0.33\$
Refraction index \$n=3.6\$
Inner losses \$p_i=20 cm^{-1}\$
Now I have to determine the ...
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Getting the optical power of a UV-LED using a spectrometer data
if it is possible can you let me know the way to get the radiated power of a UV-LED using the output data from the "Ocean optics- Maya pro 2000" spectrometer, or the calculations needed to ...
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what is the reason behind DC level shift of the optoisolator ouput(collector of photo transistor) terminal?
i am using SFH-610A optoisolator to switch 1KHZ PWM signal. on input side of opto i am triggering from micro controller with series resistor 500 ohms. and on the output side i have pull-up of 3.3V ...
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Resistor between vcc and control signal in a rpi controlled relay board
I have been researching to design a rpi controlled relay board and I found these two schematics from two companies. Personally I trust the company in the image above but I am confused about R3 (10k) ...
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How to share a digital signal between circuits?
Please see this :
The Task
I'm trying to create a single module which can safely share a single digital signal.
The idea is that each (identical) module can monitor the status of the signal, and can ...
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Please help me understand how this inductive proximity sensor works
I'm trying to build out an optocoupler circuit to connect a new proximity sensor to my 3D printer and want to understand how it behaves before implementing.
It's a Printrbot Simple Metal, Printrboard ...
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3
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471
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A laser driver (MLD203P1) with an external Bias-Tee for modulation
As the title says, I would like to add an external Bias tee to modulate a high frequency signal into a laser diode, because the laser driver I have chosen does not have a built-in modulation circuit. ...
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Opto-isolation amplifier output is too off
(As a follow-up to an earlier question answered by the community - thanks!) So I've got the test circuit setup using the HCPL 7520 (datasheet) now and planning to use an Arduino Uno to measure the ...
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3
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Opto-isolation amplifier giving no output
First of all, thanks to the community for having such helpful answers here - don't post very often but here's one I could really do some help with.
I want to measure a voltage range of 0-100V DC in an ...
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