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Perhaps a fast opamp to boost the signal level, then fast comparator to convert to logic signal, followed by monostable to stretch the pulses. 465mV is probably enough with a fast comparator to avoid the need for the opamp.

The ADC inside Teensy is far too slow for this type of narrow pulse. You will need to handle this as a 3V a digital signal. A voltage comparator is probably the best way, but TL714 is probably too slow. I'd recommend trying a faster chip, like...

I tried to look up the minimum pulse width needed for the GPIO interrupt hardware, but couldn't find it in NXP's documentation. But as a general rule of thumb, usually 2 clock cycles are needed because they almost always use a circuit that...

Hi Paul, Thank you for your explanation. That means I have to convert the analog pulse to a digital pulse on the order of 3 V. I think 150 MHz would do the job for detecting the pulse only, I am not measuring them, just detecting them. Any idea...

Ed, I tried using a second stage Op-Amp for additional gain, but there was too much signal degradation. I switched to the TL714 comparator and got a 4 V digital pulse but more than half of the square pulse was below the 0 V baseline on the...

If you boost the gain on your Trans Impedance Amplifier (TIA) to output 0 -> 3.3Volts you could send it directly into the Teensy 4.x and count pulses with no problem, otherwise you could send it into the A/D and then do anything you want with the...

Hi Ed, Thank you for the reply. So it is better to increase the output pulse to an amplitude in the range of 2-3 V? I can do that by increasing the feedback resistance but it will decrease the bandwidth, which I would not prefer. You mentioned...

Hi everyone, Hope you are doing well. I need some help and guidance on building a pulse/frequency counter with a microcontroller under $50. I have analog pulses 486 mV in amplitude and 100 ns wide that are coming from my photodiode TIA at...