Electrical – Bandwidth analysis for photodiode TIA using matlab

Try this

^{simulate this circuit – Schematic created using CircuitLab}

The 7414 is a Schmitt trigger, and will handle even very slow transitions of light level. If you just use an ordinary gate, and the input changes slowly, you may get multiple triggers as the input responds to noise right at the threshold. Conversely, if your light pulse has a very fast turn-on AND turn-off, you may not need the inverter at all.

R1 is used to set sensitivity. But note that a "real" 7414 needs 1.2 mA of photodiode current, plus the resistor current to operate. If your light source is not intense enough, the photodiode won't be able to pull the input low. In that case you can try a 74LS14 which, like all 74LS, only requires 0.4 mA. If that's still too much, go to a 74HC14. It will work just fine driving the original 7400 series.

And, of course, if you need the clock on the falling edge of the light pulse, just add another inverter.

The circuit on the right side makes use of an LM 108 and a capacitor on pin 8 ( due to the datasheet pin 8 of the op amp stands for Comp). Not having this pin on L358 what can I do for that?

The LM108 has pins for external compensation. As you've already figured out you will not find these pins on the LM358 because the LM358 is internally compensated (e.g. the capacitor is within the chip). So if you use the LM358 you don't need that capacitor.

Morever the arduino analog pin normally indicates a value btw 0-1023. Now using the op amp I get a maximum value of 767 ( this means approx. 3/4 of 1023). Is there any particular reason for that or am I doing any mistake?

The output of your amplifier does not generate a voltage that the arduino would interpret as full scale. You can increase the amplification by choosing a bigger resistor between the output and the negative input. If you want your amplification 25% higher just make the resistor 25% bigger.

Note that the voltage at the LM358 output can't go as high as the supply voltage. It will always have a maximum output voltage that is 1.5V to 2V below the supply. That means, if your arduino analog input would give you a full scale at - lets say - 5V, then you need to supply your OpAmp with 7V at least. Otherwise the output will clamp and never reach the full scale.

You'll also likely don't want to connect your OpAmp output directly to the analog input. Analog inputs have a maximum input voltage, and you should never exceed this. If you do current will flow through a protection diode. If the current is to large that could blow up your arduino. Adding a resistor between the OpAmp output and the analog input will limit the current without influencing the reading much. 2.2k is what I usually use as a rule of thumb value.