Chapter 3 Digitizer Basics
Analog Bandwidth
Analog bandwidth describes the frequency range (in hertz) in which a signal can be digitized accurately. This limitation is determined by the inherent frequency response of the input path—from the tip of the probe to the input of the ADC—which causes loss of amplitude and phase information. Analog bandwidth is the frequency at which the measured amplitude is 3 dB below the actual amplitude of the signal. Figure 3-2 illustrates the effect of analog bandwidth on a high-frequency signal. The result is a loss of high-frequency components and amplitude in the original signal as the signal passes through the digitizer.
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Figure 3-2. Analog Bandwidth
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