CS8120YD14 Cherry Semiconductor Corporation, CS8120YD14 Datasheet - Page 7

• Manufacturer Part Number: CS8120YD14
• Description: 5V/ 300mA Linear Regulator with and ENABLE RESET
• Manufacturer: Cherry Semiconductor Corporation

The maximum power dissipation for a single output regu-
lator (Figure 7) is:
where:
Once the value of P
sible value of R
The value of R
the package section of the data sheet. Those packages
with R
Figure 7. Single output regulator with key performance parameters
labeled.
Figure 6. Circuit showing output compensation capacitor.
*C
**C
V
V
V
I
tion, and
I
I
1
OUT(max)
Q
OUT(max)
P
IN
2
is required if regulator is far from power source filter.
IN(max)
OUT(min)
D(max)
is required for stability.
is the quiescent current the regulator consumes at
QJA
I
= { V
's less than the calculated value in equation 2
IN
is the maximum input voltage,
.
in a Single Output Linear Regulator
is the maximum output current for the applica-
is the minimum output voltage,
IN(max)
Calculating Power Dissipation
QJA
QJA
can then be compared with those in
R
can be calculated:
Ð V
D(max)
QJA
}
Control
Features
OUT(min)
Regulator
=
Smart
V
is known, the maximum permis-
IN
150¡C - T
C
0.1mF
1
} I
*
P
I
Q
OUT(max)
D
A
+ V
I
IN(max)
OUT
ENABLE
Application Notes: continued
I
Q
V
CS-8120
OUT
(1)
(2)
7
RESET
V
will keep the die temperature below 150¡C.
In some cases, none of the packages will be sufficient to
dissipate the heat generated by the IC, and an external
heatsink will be required.
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.
OUT
QJC
QJA
R
R
R
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.
R
C
RST
RST
R
QJA
to mP
RESET
Port
= R
QJC
Heat Sinks
+ R
QJA
C
10mF
2
QCS
**
:
+ R
QSA
5V to mP and
System
Power
QCS
and R
QSA
(3)