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Horacio,
Yes that looks good. I did a quick simulation and came to the same conclusion - 3.3pF for compensation with 2.2k. Transient looks OK as well. You should be able to run it directly from 5V/0V because you have a constant bias current from your laser anyway.
Keith
I'm going to build it and post a feedback as soon as possible.
Make sure there is some capacitance across that feedback
Keith.
I have had a quick look and the opamp shouldn't be slew rate limiting. Two other questions: what is the photodiode and are you varying the laser modulation by optical filters rather than changing the modulation electronically?
Keith.
I would test the photodiode with a 50 ohm load, if there's a similar effect.
And check the OP output waveform.
What photodiode specification are you exceeding? They normally only limit power dissipation, not light level. I have never seen them reduce sensitivity due to light level, but then I am usually dealing with too little light, not too much.
Have you looked at the opamp output waveform and operating voltage levels to make sure nothing is clipping?
Keith.
If so, we shouldn't diescuss about an amplifier problem any more.I did the same measurement with the photodiode alone, loaded with 50 ohm. And I found the same behavior.
So have they thought about an explanation?This behavior is reported in many papers but only for high frequency communications apps.
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