Electronic – Will this photodiode circuit filter this frequency

filteroperational-amplifierphotodiode

I have the following circuit with a photodiode and an LM358P where I intend to blink an LED at around 20kHz. I want to work on it. I have made a calculation through 1/(2piRC), and got something around 33khz. Is this correct? Will this circuit work with a 20kHz frequency ?

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Best Answer

got something around 33khz. Is this correct? Will this circuit work with a 20kHz frequency ?

It's nearer 34 kHz but yes this will do the job adequately with some rounding of the output signal.

However, the output signal will clip at around 3 volts typically with an LM358 and, that op-amp will introduce some extra low pass filtering due to its small bandwidth and slew rate limitations on the output: -

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