Agilent Technologies 4349B, Manual

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4349B
A dditional Error Due to V oltage Source Noise
The error caused by the DC voltage source's noise appears as a measurement value uctuation.
Figure 6-5 shows an estimation of the additional error caused by the DC voltage source's noise
under the following conditions:
External DC voltage output : 100 V
4349B Measurement Speed : 30 ms
DC voltage source performance :
Ripple 5 Vrms(@50 Hz)
Wide band nosie 1 Vrms/
p
H z (@50 Hz)
Switching noise < 10 mVrms(@100 Hz)
Note
The DC voltage source's output resistance is assumed to be 0 in this example .
Figure 6-5. A dditional Error Due to V oltage Source Noise
F or example , when measuring a capacitor of 2 G resistance and 1 F capacitance , the leakage
current (50 nA=100 V/2 G) can be measured within 10% additional error . That is , the
measurement value will uctuate from 45 nA to 55 nA (or 1.82 G to 2.22 G).
Figure 6-5 shows the measurement error due to the external DC voltage source only . T o
estimate the total system measurement error , it is also necessary to include the 4349B's
measurement accuracy in addition to the error shown in Figure 6-5.
6-10 Application Measurement