TiePie Handyscope TP450, Руководство пользователя

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The higher the resolution , the more levels are available and
the more accurate the input signal can be reconstructed. In figure
3.7 , the same signal is digitized, using two different amounts of
levels: 16 (4-bit) and 64 (6-bit).
Figure 3.7: The effect of the resolution
The Handyscope TP450 measures at 16 bit resolution (2
16
=65536
levels). The smallest detectable voltage step depends on the input
range. This voltage can be calculated as:
V oltageStep = F ullInputRange/LevelCount
For example, the 2 V range ranges from -2 V to +2 V, therefore
the full range is 4 V. This results in a smallest detectable voltage
step of 4 V / 65536 = 61.0
µ V.
3.5 Signal coupling
The Handyscope TP450 has two different settings for the signal
coupling: AC and DC. In the setting DC, the signal is directly
coupled to the input circuit. All signal components available in the
input signal will arrive at the input circuit and will be measured.
In the setting AC, a capacitor will be placed between the input
connector and the input circuit. This capacitor will block all DC
components of the input signal and let all AC components pass
through. This can be used to remove a large DC component of the
input signal, to be able to measure a small AC component at high
resolution.
12
Chapter 3