Questions tagged [photodiode]
A photodiode converts light to an electric current.
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How to simulate non-invasive blood glucometer in Proteus?
I'm working on a project in which I'm trying to create a non-invasive blood glucometer using NIR light and a photodiode.
The glucose level is determined by the amount of light absorbed by the blood, ...
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HV Rectifier output for APD biasing
I am trying to convert low 5V or 12V to -200V using this device. Which converts it using transformer and rectifier at the output:
Can I just attach HV OUT to bias APD detectors? Or is there any ...
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Triggering generic transistors with UV or green light?
Flashes of UV light can create electron-hole pairs in transistors. Or at least reports of the "UV flash bug" claim this happens in microprocessors. People observed raspberry pies reset when ...
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If we change the PV panel, should we also change the MPPT controller block?
I have 6kw PV panel, in case of partial shading it's capacity reduces to 3kw. But, the MPPT tracker I designed it specifically for that 6kw rating, now because of partial shading the same MPPT tracker ...
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Receiver circuit design testing
I am trying to make a receiver circuit that is able to receive an LED input (further down the line receiver input from a laser).
Firstly, I am trying to test the photodiode that will be used. I am ...
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Photodiode Current Calculation for Simulation
I am designing a transimpedance amplifier and was trying to simulate the circuit to study its characteristics. I came across this online design tool provided by Analog Devices that builds the ...
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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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Making a low-cost in situ fluorometer with Arduino
I am making a low cost in situ fluorometer with Arduino based on this paper
The paper lists all the instruments required for the device, but since some of the products were outdated/hard to find, I ...
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I'm looking for a very sensitive photodiode [closed]
I'm working with a custom board that has a simple input to detect a closed switch, and I'm hoping to use it as a light sensor. I was thinking of just attaching a simple photodiode (Like this one: ...
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High frequency photodiode laser receiver strange output
We've built this transimpedance amplifier circuit to receive 10kHz pulses from a laser. The laser is driven by a square wave signal generator and is pulsing correctly. We expected to see a square wave ...
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About Negative Gain in Bode Plot regarding the Op-amp Circuit Design and its Relationship with the Feedback Resistor
I am new to the circuit simulation and now I am using Tina to simulate a op-amp circuit for a photodetector. I have some questions regarding the bode plot.
Below is the circuit design, based on the ...
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Current/Voltage Amplification and Photosensitivty in Photodiode
I have a couple questions related to the same home project. I am brand new to circuits and have just started reading into photo diodes.
Q1: I have a home project goal to essentially get a photo diode ...
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Narrow bandwidth photodiode?
I'm working with robots that use IR sensors to avoid obstacles.
In my experiment, I'm using a tracking system that uses IR leds at 850 nm.
The problem is that the IR sensors detect the tracking system ...
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Barcode reader circuit from scratch [closed]
I'd like to assess how difficult/doable is to create a barcode reader from scratch or what alternatives there are.
The application is an automated storage and retrieval system. There are containers ...
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Photo Diode Receiver
I have designed a 5KHz Photo Diode Receiver circuit that Consists of a number of blocks. first stage of this circuit is a TIA.
I have problem with DC IR Light (Like SUN Light), when sun light shine on ...
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Modelling Biased APD In Integrator Circuit
I want to model a biased APD (Avalanche Photodiode) whose current output feeds into an integrator. For the IC I will be using, TI recommends the following configuration for an unbiased photodiode.
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Photodiode Modelling
I want to model an Avalanche Photodiode (APD) in LTSpice. Is the below an appropriate representation?:
simulate this circuit – Schematic created using CircuitLab
If so, why is the diode ...
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IVC 102 Integrator IC - Photodiode Simulation Issues
I am designing a circuit that integrates a signal output from an avalanch photodiode.
The component I am using is the ICV102U. Before purchasing the IC, I want to run a few simulations using LTSpice. ...
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Optical Receivers and Amplifiers
I have been doing some past papers for a university module I am studying. I am not from an electrical engineering background so don’t really know how to attempt the question attached. I would really ...
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Photodiode pulse detect system
We have a laser signal detection system as shown in the figure below. In this system, we want to detect the incoming laser pulse. The MCU will detect the incoming pulse and perform its operations ...
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Transimpedance and resistor bias in IR transmitter
I've been studying the optical (photo-diode) transmitter and receiver circuit for a while. There's a case that I can't understand the difference. In the optical receiver bias circuit, what is the ...
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Arduino: convert analogRead from photodiode in a distance in cm or mm?
I am doing a very simple project on Arduino consisting of an IR LED and a photodiode that measure the distance from an obstacle. I am using an Arduino Nano BLE that has a 12-bit ADC converter.
I am ...
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Map a specific photocurrent range from photodiode to ADC range 0 V .. 3.3 V
Problem
Measure tiny current fluctuations in photo-diode. Lets say that photo-diode outputs \$2300\text{ nA} \pm 100\text{ nA}\$. Then that needs to be mapped to ADC. So \$2200\text{ nA} .. 2400\text{ ...
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Does the responsivity change with temperature of a pin photodiode?
I have a more fundamental question on which I can not find any answer, maybe there is some inherent understanding I am missing. I am currently trying to evaluate the temperature behaviour of a InGaAs ...
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How to configure / construct a CMOS sensor to act on changing signals only?
You all probably know how a CMOS sensor works, at least in general. In short, it consists of a lot of pixels (photodiode plus amplifier and so on), and each pixel is read out individually (different ...
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Photodiode square wave positive duty cycle lower and lower
I drive an IR LED with a 50% duty cycle square wave and receive its signal with a photodiode. If I take the photodiode farther and farther from the LED, the signal's positive duty cycle is lower and ...
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Gain of photodetectors
I found this in a lecture about "Optical Wireless Communications." It is slide 15.
Does anyone have idea how gain was computed?
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What is the I_R current for this avalanche photodiode?
This is the datasheet of the APD I got.
There's 'I_R' at test condition for breakdown voltage.
What is this current I_R?
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APD (avalanche photodiode) responsivity problem
I'm experiencing a few problems with responsivity of APD (model: First Sensor AD500-8-S1).
This is the circuit I tried to make.
Just simply apply voltage (positive polarity) to the cathode for ...
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What is the role of capacitor of avalanche photodiode circuit?
I got few questions about apd circuit.
There's a capacitor between the cathode and ground.
What is the role of this capacitor?
In picture, it say's 'min. 0.1uF, closest to APD', however, the ...
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I am trying to design a basic CMOS Image sensor
I am new to electronics so I might be doing some bad mistakes on my design but anyways,
I'm trying to build a CMOS Image sensor using Proteus, and I couldn't find some basic tutorial to follow, Yet I ...
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Ways for comparing start and stop pulses in time of flight
I am using an LM358 as an astable multivibrator. I am pulsing an 850nm IR LED at 1 Hz. The IR LED has a carrier wave of 38 kHz generated by a 555 timer.
I have a 38 kHz IR TSOP as receiver. It outputs ...
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Multi stage & gain opamp output voltage issue
I am currently facing an issue with an opamp circuit.
The design consists of a transimpedance amplifier followed by a buffer stage and then followed by 6 non inverting gain stages (each stage 4 times ...
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Help identifying 3-pin open-collector photo-transistor-like component
Can someone help identify the 3 pin photo device (not the entire module) on this "Icstation 5V Light Sensor Module"? (may be same as this one
It seems to act as a photo-transistor, but yet ...
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APD Module and A/D card
I want to make a LDV/PDPA device for measuring the diameters of droplets. For this device I need to use APD photodiode to gather the scattered light from droplets. I searched for PADs and found a ...
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Weird DC Response in Photodiode TIA Circuit
I'm building a photodetector circuit designed to measure the amplitude of a 1 kHz signal.
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I have reworked the feedback resistor (R2) to 383 kΩ and changed the bandpass filter to have a gain of 15.
I ...
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Photodiode TIA circuit - filtering ambient light
In my lab, we are working on developing an open-source online biomass sensor.
The basic idea is to shoot an IR light source to a colloidal solution and then measure the reflected light using a ...
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Altium Designer PCB Layout Review
I am very new to PCB design and have recently completed schematic capture and PCB layout of an optical detection circuit using Altium Designer. My custom PCB consists of a photodiode, transimpedance ...
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Finding Values For Cd and Ccm
When choosing an op amp for your system based on the system's required bandwidth, the value for Cin must be calculated for the required gain-bandwidth product. I understand that Cj is the junction ...
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Common Mode Input Capacitance
If I were to follow the same circuit diagram as provided in the image above, must I include Ccm myself? Or is this capacitance value apart of the op amp itself?
Wondering the same for diode ...
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Input Source Capacitance Value for GBW Calculation
For the calculation of GBW product for a photodiode:
Which diode capacitance value do I use for the input source capacitance (Cs)? I am having trouble understanding the difference between the 400pF ...
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Interfacing MCP3302 ADC with Arduino Micro SPI Help
I am very new to hardware design and am making an optical detection circuit using a photodiode. I simply need to interface with the photodiode and save the output voltage values on Arduino IDE
...
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Gain of transimpedance op amp
I am trying to calculate the gain-bandwidth product of a project where I am reading photodiode output current measurements. I aim to find an op-amp to buy to use as a transimpedance amplifier. The ...
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Choosing the Right Op Amp for Photodetection
I aim to use a silicon PIN photodiode to detect light emitted from a set of chemical reactions from a chamber. I am having trouble choosing an appropriate op amp to order to convert the photodiode's ...
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What is this Digilent Analog Discovery device doing in this experiment?
I'm a novice to electronics, and I was wondering if someone would clarify an experiment I just witnessed. A photodiode was set up to receive some signal. This signal is then read by a transimpedance ...
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Can I simply adjust the output power of these laser diodes to meet my specifications? If so, then what are the consequences of doing such a thing?
I need a CW laser diode, with an integrated photodiode, with wavelength around 800nm and power 1-1.5mW. Although I didn't find anything that exactly matching my specifications, I did find this from ...
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Using TSOP17 and 555 to measure distance
I am trying to design a simple circuit that measures distance.
I will use an IR emitter and an IR reciever photodiode, and just measure the time between the moment the pulse was sent and when it was ...
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Identifying / distinguishing between PIN photodiode and avalanche photodiode
Is there any way to determine whether an unidentified photodiode is a regular PIN photodiode or is an avalanche diode? The photodiode is part of a small scintillation detector unit.
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Current feedback amplifier
I was wondering whether is it ok to connect a current feedback amplifier (CFA) after the TIA stage to obtain high swing and large bandwidth. I am not sure how to connect the CFA after the TIA stage.
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Does the photoelectric interaction occur mostly over the depletion zone of a photodiode?
It is important for some photodiodes like the PIN diode to have a large depletion zone. This is to achieve a large area that allows for conversion of photons to electron-hole pairs.
Why does this ...
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