Input Referred noise is calculated for the circuit that is to be used for characterization of photodiodes. For the biasing 12V was used from SR560 as it provides cleaner voltage as compared to other voltage supplies.
**Attachment 1: The Circuit Diagram TIA**
>> the TIA with a gain of 5.1k
**Attachment 2: Input Referred noise of TIA **
The input-referred current noise across the TIA was measured using SR785 and was compared against the graph obtained from ZERO simulation.
**Attachment 3: Differential Circuit**
>> gain of 100
**Attachment 4: Input Referred noise of Differential Circuit**
The input-referred voltage noise measured using SR785 and was compared against the graph obtained from ZERO simulation.
**Attachment 5: Whitening Filter Circuit**
>> gain of 10
**Attachment 6: Input Referred noise of Whitening Filter Circuit**
The input-referred voltage noise was measured using SR785 and was compared against the graph obtained from ZERO simulation.
Some points that were observed:
*** I am observing deviation from simulated results at higher frequencies. Presently, I am unable to understand the cause of this deviation.
*** At low frequencies deviation from simulated results is perhaps caused due to 60Hz harmonics and 1/f noise. |