SRS Labs SR555, Operation Manual, Page: 5 / 10

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Current
noise
density
(fA/

Hz)
Frequency (Hz)
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Current
noise
density
(fA/

Hz)
Frequency (Hz)
Cs = 1.2nF
Cs is the input shunt capacitance
Cs is the input shunt capacitance
Cs = 120pF
Cs = 12nF
Cs = 1.2nF
Figure 3: SR555 input
current noise density
Figure 4: SR556 input
current noise density