CS8147 Cherry Semiconductor Corporation, CS8147 Datasheet - Page 7

• Manufacturer Part Number: CS8147
• Description: 10V/5V Low Dropout Dual Regulator with ENABLE
• Manufacturer: Cherry Semiconductor Corporation

A heat sink effectively increases the surface area of the
package to improve the flow of heat away from the IC and
into the surrounding air.
Each material in the heat flow path between the IC and the
outside environment will have a thermal resistance. Like
series electrical resistances, these resistances are summed
to determine the value of R
where:
R
R
are functions of the package type, heatsink and the inter-
face between them. These values appear in heat sink data
sheets of heat sink manufacturers.
Figure 1: Dual output regulator with key performance parameters
labeled.
QJC
QJA
V
R
R
R
IN
QJC
QCS
QSA
, it too is a function of package type. R
appears in the package section of the data sheet. Like
= the junctionÐtoÐcase thermal resistance,
= the caseÐtoÐheatsink thermal resistance, and
= the heatsinkÐtoÐambient thermal resistance.
I
IN
R
QJA
= R
}
Control
Features
Regulator
QJC
Heat Sinks
Smart
+ R
QJA
:
QCS
I
Q
+ R
QSA
I
I
OUT 1
OUT 2
QCS
Application Notes: continued
and R
V
V
QSA
OUT 1
OUT 2
(3)
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