BK Precision 885 Manual De Instrucciones página 36

measurement range from 1m to 10M.
H
CUR
H
POT
L
POT
L
CUR
(a) CONNECTION
1m 10m 100m 1
(c) TYPICAL IMPEDANCE
MEASUREMENT RANGE(£[)
 Eliminating the Effect of the Parasitic Capacitor
When measuring the high impedance component (i.e. low
capacitor), the parasitic capacitor becomes an important issue
(Figure 3.6). In figure 3.6(a), the parasitic capacitor Cd is
paralleled to DUT as well as the Ci and Ch. To correct this
problem, add a guard plane (Figure 3.6(b)) in between H and L
terminals to break the Cd. If the guard plane is connected to
instrument guard, the effect of Ci and Ch will be removed.
DUT
4T
10 100 1K 10K 100K 1M
V
A
(b) BLOCK DIAGRAM
H
CUR
H
POT
L
POT
L
10M
CUR
(d) 4T CONNECTION WITH SHILDING
Figure 3.5
33
DUT
DUT