3.5.8 Temperature Characteristics of Thermistor
Calculate the resistance of the thermistor (R
X
) at the operating temperature T
X
(
C) using the following
equation (9). Variation of resistance by temperature is shown in Figure 3-11 and Table 3-14.
Equation (9):
298
1
T
+
273
1
×
B
EXP
×
R
=
R
X
25
X
-
R
X
: Resistance
at
T
X
C (
Ω
)
R
25
:
Resistance at 25
C
30k
Ω
5%
B
:
B
value
3950K
3%
T
X
:
Temperature detected by thermistor (
C)
EXP (A)
:
The "A" th power of natural logarithm e (2.71828)
1
10
100
1000
-20 -15 -10 -5
0
5
10 15 20 25
30 35 40 45 50
55 60 65 70 75 80
85 90 95 100
温度 (℃)
サーミスタ抵
抗値
(k
Ω)
Re
sist
an
ce (
k
Ω
)
Tem
(
℃
)
perature
Figure 3-10 Temperature Characteristics of the Thermistor
3-24