ADA4528-x voltage noise density characteristic versus a regular operational amplifier

Document created by analog-archivist Employee on Feb 23, 2016
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How is the ADA4528-x voltage noise density characteristic different from a
regular  operational amplifier?


1/f noise, also known as flicker noise, is inherent in semiconductor devices
and increases as frequency decreases. Therefore, it dominates noise at dc or
low frequencies. Due to the architectures of zero-drift amplifiers like the
ADA4528-x, 1/f noise is removed, similarly to a slow varying offset. This
correction becomes more effective as the noise frequency approaches dc,
eliminating the tendency of the noise to increase exponentially as frequency
decreases. The 0.1Hz to 10Hz voltage noise of a zero drift amplifier is
therefore typically much lower than a standard low noise amplifier that is
susceptible to 1/f noise.