Tektronix P6209, Инструкция по эксплуатации

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Specifications
P6209 4 GHz Probe Instruction Manual
23
Calculating DC Voltage Measurement Accuracy:
DC Voltage Measurement Accuracy (referred to input)
=
[2% of input + (2% of offset) + 37.5 mV + 3.5 mV]
where:
gain error
=
2% of input voltage (relative to offset voltage)
offset gain error
=
2% of effective offset at probe tip
output zero
=
37.5 mV effective at probe tip (worst case, but
does not include any oscilloscope offset control voltage error)
linearity error
1
=
0.1% of 1.75 V (3.5 V full scale)
=
3.5 mV
High Error Example.
To determine the maximum specified DC error
when measuring a PECL logic high of approximately 4.1 V with
probe offset set to 3.7 V:
(2% of input voltage
=
8 mV, +
2% of offset voltage
=
74 mV, +
output zero
=
37.5 mV (worst case value), +
linearity error
=
3.5 mV)
=
123 mV
Low Error Example. To determine the maximum specified DC error
when measuring a LVDS low of approximately 1.0 V without any
probe offset (0 V):
(2% of input voltage
=
20 mV, +
2% of offset voltage
=
0 mV, +
output zero
=
5 mV (effective offset at probe tip due to typical
offset value of 1 mV at probe output), +
linearity error
=
3.5 mV)
=
28.5 mV
1
The linearity specification is rated with a segmented range (see page 22).
The linearity error is higher at the extreme ends of the dynamic range.