Datasheet

Application Note (Continued)
TABLE 1. θ
JA
Different Heatsink Area
Layout Copper Area Thermal Resistance
Top Side (in
2
)* Bottom Side (in
2
)(θ
JA
,˚C/W) SOT-223 (θ
JA
,˚C/W) TO-252
1 0.0123 0 136 103
2 0.066 0 123 87
3 0.3 0 84 60
4 0.53 0 75 54
5 0.76 0 69 52
61066 47
7 0 0.2 115 84
8 0 0.4 98 70
9 0 0.6 89 63
10 0 0.8 82 57
11 0 1 79 57
12 0.066 0.066 125 89
13 0.175 0.175 93 72
14 0.284 0.284 83 61
15 0.392 0.392 75 55
16 0.5 0.5 70 53
*Tab of device attached to topside copper
LMS8117A
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