Questions tagged [photodiode]
A photodiode converts light to an electric current.
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What should I make of this spectrum analyzer data?
Here I have two signals that I placed into a spectrum analyzer. Channel 1 (yellow) comes from an avalanche photodiode + TIA circuit that has a 50 Ω output resistor, which is directly connected via BNC ...
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Wideband Photodiode Amplifier (>= 50MHz) and Obnoxiously Big Input Bias Currents of Current Feedback Amplifiers
I'm toying with the idea of building a >50MHz Bandwidth Photodiode Amplifier, built around a 1GHz AD8009ARZ Current Feedback Amplifier. I got two photodiodes that have a bandwidth exceeding 1GHz.
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How to optimize wavelength of a photodiode exclusively to single wavelength?
I have a laser diode with parameters:
a. Laser Wavelength: 785 nm
b. Laser Power: (0 – 100) uW
c. Laser Modulation: 1 KHz
I need to design a photodiode circuit based on these parameters. I plan on ...
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How do I modulate the output power of a laser diode at 1 kHz? [closed]
I am planning to use L785P5 laser diode from Thorlabs, which has a maximum output power of 5 mW. As per my requirement, I need power output in the range of 0-100 µW. So how do I go about reducing the ...
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Photodiode Signal Temporal Broadening Below Saturation
I'm a physics PhD student working on a project to use silicon photodiodes for detection of longwave infrared (6-10um) ultrashort pulses. (Specifically doing higher-order autocorrelation) Despite ...
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Photodiode Circuit Output Saturating to 0V. Is there a way to salvage these boards?
My colleague and I recently designed and ordered a PCB intended to capture red laser light using a SFH2440 photodiode. We used the analog devices photodiode circuit design wizard to design the ...
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Why does photodiode junction capacitance affect operating bandwidth? (from a semiconductor physics model perspective)
Here is a typical equivalent circuit diagram of a photodiode.
I feel like this circuit model broadly makes sense to me. You have a diode, in parallel with the junction capacitance. The photocurrent ...
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How to Ground a Photodiode and TIA combination
I have a TIA circuit as below, In simple terms the Photo diode is a APD C30955EH and Circuit is supposed to work up to 100Khz signals digitalization.
The supply which is powering the circuit is a ...
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TIA with reverse bias adapted
I have adapted my circuit of the last post TIA circuit with reverse biases photodiode, thanks for the feedback, but it still doesn't work. I have removed the voltage divider for the positive input ...
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Issue with Gain Compensation Circuit in MLD203P1 Laser Driver
I am experiencing difficulties with the gain circuit of Thorlabs' MLD203P1 laser driver. Despite adhering to the datasheet and evaluation manual, my laser diode is burning out, and the current ...
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Confusion with a photodiode circuit
I'm using this photodiode with a simple circuit as follows:
And in my setup the photodiode sees the same light input meaning same average power from a laser source which is less than a few mW ...
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Flame Sensor Supply Voltage Range
I have this flame sensor module which I am going to use for a project. Upon closer inspection, I can see that the maximum supply voltage of the LM393 comparator IC used is 30V according to this ...
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Negative offset voltage on analog input in data acquisition device (DAQ) connected to a photodiode in the dark
I have a data acquisition device (DAQ): USB-6002 from National Instruments (NI). I am recording an analog voltage from a (cathode-grounded) photodiode through a variable resistance (50-100k Ohms).
I ...
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Transimpedance amplifier oscillating at high gain setting on PCB only
I am trying to make a bare minimum transimpedance amplifier for a very large Si photodiode (Thorlabs FDS1010). My circuit is just like in the picture except my digipot is an AD5272-100kohm and my ...
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Modulation Bandwidth of LED
Following on my previous post I have photodiode connected to OpAmp in inverting transimpedance configuration. (Circuit diagram can be found in previous post).
Excitation source is 4000K LED with ...
