4. Application
4.1 Test Leads Connection
Auto balancing bridge has four terminals (H
CUR
, H
POT
, L
CUR
and
L
POT
) to connect to the device under test (DUT). It is important to
understand what connection method will affect the measurement
accuracy.
z
2-Terminal (2T)
2-Terminal is the easiest way to connect the DUT, but it contents
many errors which are the inductor and resistor as well as the
parasitic capacitor of the test leads (Figure 3.1). Due to these
errors in measurement, the effective impedance measurement
range will be limited at 100
Ω
to 10K
Ω
.
R
H
CUR
H
POT
DUT
(b) BLOCK DIAGRAM
DUT
V
A
Co
o
L
o
R
o
L
o
(a) CONNECTION
(c) TYPICAL MPEDANCE MEASUREMENT RANGE(£[)
2T
1m 10m 100m 1
10
1K 10K 100K 1M
100
10M
L
POT
L
CUR
Figure 3.1
40