Datasheet

13
LT1302/LT1302-5
APPLICATIONS INFORMATION
WUU
U
As an example, consider a boost converter with the
following specifications:
V
IN
= 3V
V
OUT
= 6V
I
OUT
= 700mA
Total power loss in the LT1302, assuming R = 0.15Ω and
V
D
= 0.45V, is:
Using the CS8 package with 100 sq. mm topside and
backside heat sinking:
∆T = (312mW)(84°C/W) = 25.9°C rise
With the N8 package:
∆T = 31.2°C
At a 70°C ambient, die temperature would be 101.2°C.
PmA
mW mW mW
D
=
()()
+
−
××












−
+
−
××


























+
()
+−
()
=+=
700 0 15
6045
3
07 6 015
3
6045
3
07 6 015
3
0 7 6 0 45 3
27
223 89 312
2
2
.
.
..
.
..
..
Ω