R44E.pdf

Dec.17,2012

• This catalog has only typical specifications. Therefore, please approve our product specifications or transact the approval sheet for product specifications before ordering.

6

1. Zero-power Resistance of Thermistor: R

2. B-Constant

..............(1)

R: Resistance in ambient temperature T (K)

(K: absolute temperature)

B: B-Constant of Thermistor

as (1) formula

B=

3. Thermal Dissipation Constant

When electric power P (mW) is spent in ambient

there is a formula as follows

..................(3)

C: Thermal dissipation constant (mW/°C)

Thermal dissipation constant is varied with dimensions,

measurement conditions, etc.

4. Thermal Time Constant

Period in which Thermistor's temperature will change

63.2% of its temperature difference from ambient

Resistance vs. Temperature

!Basic Characteristics

!Performance

Thermal Time Constant

Item

Resistance

Condition

Measured by zero-power in specified ambient temperature.

Rated Electric Power

Shows the required electric power that causes Thermistor's temperature to rise to a specified temperature by self heating,

at ambient temperature of 25 °C.

Permissive Operating Current

It is possible to keep Thermistor's temperature rising max. 1°C.

Thermal Dissipation

Constant

Shows necessary electric power that Thermistor's temperature rises 1°C by self heating.

It is calculated by next formula (mW/°C).

B-Constant

Calculated between two specified ambient temperatures by next formula.

B =

1/T

P

C =

T

–20

Temperature (°C)

0

20406080

120

100

1

B=3450

B=3900

B=4100

Basic Characteristics

Time

63.2%

X

Please inquire about test conditions and ratings.