STB8827
Series Operation Manual Chapter 7 Command Reference
6.2.7
69
DC bias voltage source
0V— ± 5V Minimum resolution: 0.5mV, Accuracy: 1% x preset 5mV
0mA—± 50mA Minimum resolution: 5
μ
A
6.3 Measurement accuracy
Test accuracy includes stability
、
temperature coefficient
、
linear degree
、
test
repeatability and calibration inter-error.
Check the accuracy of instrument should be under the following circumstances
：
a
．
b
．
c
．
d
．
e
．
warm-up time
：
≥
30 min
cable
：
0m, 1m
correct open and short correction after warming up
DC bias is in the position of “OFF”
The range works in “AUTO” to select correct test range
6.3.1 Accuracy of
│
Z
│
,
│
Y
│
, L, C, R, X, G, B
The accuracy Ae of
│
Z
│
，
│
Y
│
，
L
，
C
，
R
，
X
，
G and B are expressed as
：
A
e
= ± [A
L
× A+
（
K
a
+K
b
+K
c
）
×100+ K
d
+K
f
]×K
e
[%]
A
：
basic test accuracy
（
figure A
）
A
L
: level correction factor
（
table A
）
K
a
：
impedance rate factor
（
table B
）
K
b
：
impedance rate factor
（
table B
）
K
c
：
calibrated interpolating factor
（
table E
）
K
d
：
cable length factor
K
e
：
temperature factor
（
table G
）
K
f
：
scan fixture modification factor
（
no adding
：
K
f
= 0, adding
：
K
f
= 0.2
）
Using condition of L, C, X, B accuracy A
e
：
D
x
（
test value of D
）
≤
0.1
Using condition of R, G accuracy A
e
：
Q
x
（
test value of Q
）
≤
0.1
When D
x
≥
0.1, accuracy factor A
e
of L, C, X, B should be multiplied by
1
D
x
2
When Q
x
≥
0.1, accuracy factor A
e
of R, G should be multiplied by
1
Q
x
2
Accuracy of G can only be available in G-B combination.
6.3.2 Accuracy of D
The accuracy of D is given by the formula below
：
A
100
e
D
e
=
The formula is only available when D
x
≤
0.1.
