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= Stage 2 Offset Compensation and Op-amp Input Stage
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This section of the circuit functions as a high impedance input for the first amplifier stage.
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As described in the previous page xy, the usage of a FET voltage follower is quite common in relation to oscilloscope front-ends.
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As described in the previous page https://es.technikum-wien.at/openlab/openlab_wiki/wikis/sig_proc_osci_research[Research on existing front-end solutions], the usage of a FET voltage follower is quite common in relation to oscilloscope front-ends.
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Due to the fact that op-amps tend to add a small offset to their output signal, it is possible that the measured signal gets level shifted and therefore distorted.
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To encounter this and for calibration reasons, this stage got modified to compensate any unwanted offset.
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This was done by adding a potentiometer to the FET which is connected to the negative voltage source. The schematic of stage 2 is shown in figure 15.
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This was done by adding a potentiometer to the FET which is connected to the negative voltage source. The schematic of stage 2 is shown in figure 1.
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