QDo you have the MAX leakage current specification of ADN2880 input(PIN2)?
AADN2880 is one of our high speed TIA device. Pin 2 is the photo-diode current
In fact, all of the TIA specs are in the datasheet table one.
Usually, we have no such leakage current characteristic test data because the
ADN2880 target average power sensitivity
Is about -24dBm or better with PD Re = 0.9A/W. For example, at the -30dBm input
optical power, the induced photo-current would be about 0.9uA.
To support the necessary BERT, the S/N ration should at least 12.7 or 14.4 to
satisfy 10^-10 or 10^-12. So, in this way, the total noise current, including
Leakage current and dark current, would be no more than 62.5nA.
If you read the datasheet Fig. 1, you will notice that the PD would get max.
3.3-0.85= 2.45V reverse bias.
At the reverse bias and various operation temperature, the PD would present
various dark currents.
And from the datasheet table one, the input referred noise current would
That means this noise dominates the resulted sensitivity.