HP 4278A - Page 42

NOTE
Range Value Cp/Cs
G Rs (ESR)
0.00pF
to
2.00pF
D.DDDDDpF
D.DDDDOuS DDD.DDDIcr2
2.01pF to 4.00pF
D.DDDDDpF
D.DDDDIDuS
DD.DDDDk0
4.01pF to 16.00pF
DD.DDDDpF
D.DDDDDUS
DD.DDDDIcil
16.01pF to 64.00pF
DD.DDDDpF DD.DDDOuS D.DDDDDk0
64.01pF to 128.0pF
DDD.DDDpF DD.DDDDp.S D.DDDDDkn
128.1pF to
512.0pF
DDD.DDDpF DDD.DODuS DDD.DDDil
512.1pF to 1024pF D.DDDDDnF DDD.ODDILS DDD.DDDSI
1024pF to
2048pF D.DDDDDnF
D.DDDDDmS
DDD.DDIX/
Open capacitance is regarded as OpF if the Open Compensation function is set to
OFF when you enter the range value. Refer to paragraph 3-12-1 for details on
Open Compensation.
If the sum of the entered capacitance and open capacitance is < 2pF, the 4278A
measures capacitance at the range value, -±0.6pF.
Maximum D and 0 Values are 0.050000 and 99999,9, respectively, and the data format for D
and 0 is fixed for all ranges.
Maximum conductance G, can be derived by using the following equation.
Gmax = 0.05 x 2n x 1 MHz x (Cp of the capacitor under test)
Maximum Rs (ESR) value can be derived by using the following equation.
Rmax = 0.05/(2 Tr x 1 MHz x (Cs of the capacitor under test))
Tab le 3-3 shows the relationship between the range value and the data format (decimal point
positioning and units).
Tab le 3-3. 1MHz High Accuracy Measurement Display Ranges
"D" in the table indicates one decimal digit.
NOTE
The maximum length of test leads which can be used for 1 MHz measurements is
2.5m.
3.3