CPC1727
Thermal Characteristics
Parameter
Thermal Resistance (junction to case)
Thermal Resistance (junction to ambient)
Junction Temperature (operation)
Conditions
Symbol
RθJC
Min
-
Typ
Max
0.3
-
Units
°C/W
°C/W
°C
-
-
33
-
Free air
-
RθJA
-
TJ
-40
100
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
2
(TJ - TA) IL(99)
RθCA
=
- RθJC
IL2 • PD(99)
TJ = Junction Temperature (°C), TJ ≤ 100°C *
TA = Ambient Temperature (°C)
IL(99) = Load Current with Case Temperature @ 99°C (ADC)
IL = Desired Operating Load Current (ADC), IL ≤ IL(MAX)
RθJC = Thermal Resistance, Junction to Case (°C/W) = 0.3°C/W
RθCA = Thermal Resistance of Heat Sink & Thermal Interface Material , Case to Ambient (°C/W)
PD(99) = Maximum power dissipation with case temperature held at 99ºC = 3.33W
* Elevated junction temperature reduces semiconductor lifetime.
R02
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