CPC1909
Thermal Characteristics
Parameter
Thermal Resistance (junction to case)
Thermal Resistance (junction to ambient)
Junction Temperature (operation)
Conditions
-
Free air
-
Symbol
R
θJC
R
θJA
T
J
Min
-
-
-40
Typ
-
33
-
Max
0.3
-
100
Units
°C/W
°C/W
°C
Thermal Management
Device high current characterization was performed using Kunze heat sink KU 1-159, phase change thermal
interface material KU-ALC 5, and transistor clip KU 4-499/1. This combination provided an approximate
junction-to-ambient thermal resistance of 12.5°C/W.
Heat Sink Calculation
Higher load currents are possible by using lower thermal resistance heat sink combinations.
Heat Sink Rating
R
θCA
=
(T
J
- T
A
) I
L(99)2
I
L
2
•
R
θJC
- R
θJC
T
J
= Junction Temperature (°C), T
J
≤
100°C *
T
A
= Ambient Temperature (°C)
I
L(99)
= Load Current with Case Temperature @ 99°C (A
rms
)
I
L
= Desired Operating Load Current (A
rms
), I
L
≤
I
L(MAX)
R
θ
JC
= Thermal Resistance, Junction to Case (°C/W) = 0.3°C/W
R
θ
CA
= Thermal Resistance of Heat Sink & Thermal Interface Material , Case to Ambient (°C/W)
* Elevated junction temperature reduces semiconductor lifetime.
R03
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