L1087 Datasheet, PDF (5/10 Pages) National Semiconductor (TI) – 800mA fixed and adjustable low dropout linear regulator

ΞϓϦέʔγϣϯɾϊʔτ ( ͖ͭͮ)
͢ࢉܭʹ࣍Δύϥϝʔλ͸ɺ࠷େڐ༰Թ౓্ঢ T_R(max) Ͱ͢ɻ
T_R(max) ʹ T_J(max) ʵ T_A(max)
͜͜ͰɺT_J(max) ͸࠷େڐ༰઀߹෦Թ౓ (125 ˆ ) ͰɺT_A(max)
͸ͦͷΞϓϦέʔγϣϯ͕࢖༻͞ΕΔ࠷େपғԹ౓Ͱ͢ɻ
ࢉग़ͨ͠஋ T_R(max) ͱ P_D Λ༻͍Δͱɺ઀߹෦ - पғؒ೤఍߅
(В_JA) ͷϫʔετ஋͸ɺ࣍ͷΑ͏ʹ͢·͖Ͱࢉܭɻ
В_JA ʹ T_R(max)/P_D
В_JA ͷ஋͕ɺSOT-223 ύοέʔδͰ 136 ˆ /W Ҏ্ɺTO-252 ύο
έʔδͰ 92 ˆ /W Ҏ্ʹͳΔ৔߹͸ɺύοέʔδࣗମͰे෼ͳ์
೤Λߦ͑ΔͷͰɺώʔτγϯΫ͸ෆཁͰ͢ɻ ࢉग़ͨ͠В_JA ͷ஋͕
͜ΕΒͷϦϛοτ஋ΛԼճΔ৔߹͸ɺώʔτγϯΫ͕ඞཁʹͳΓ·͢ɻ
ઃ͢ܭΔࡍͷσʔλͱͯ͠ɺ͞·͟·ͳώʔτγϯΫ໘ੵʹର͢Δ
SOT-223 ͱ TO-252 ͷВ_JA Λ Table 1 ʹࣔ͠·͢ɻ͜͜ͰВ_JA ͷ
ଌఆͷͨΊʹ࢖༻ͨ͠ಔഩύλʔϯ͸ɺʮΞϓϦέʔγϣϯɾϊʔ
τʯͷ࠷͢·ࣔ͠ʹޙɻ Figure 7 ͱ Figure 8 ͸ɺTable 1 ͱಉ͡
಺༰ͷςετ݁ՌΛද͍ͯ͠·͢ɻ
Figure 9 ͱ Figure 10 ʹ SOT-223 ͱ TO-252 ͷ࠷େڐ༰ଛࣦͱ
पғԹ౓ͷؔ܎Λࣔ͠·͢ɻFigure 11 ͱ Figure 12 ͸ SOT-223
ͱ TO-252 ͷ࠷େڐ༰ଛࣦͱ์೤ΤϦΞͷ໘ੵͷؔ܎Ͱ͢ɻ
Layout
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TABLE 1. В_JA Different Heatsink Area
Copper Area
Top Side (in²)*
Bottom Side (in²)
0.0123
0
Thermal Resistance
(В_JA, ˆ /W) SOT-223
136
(В_JA, ˆ /W) TO-252
103
0.066
0
123
87
0.3
0
84
60
0.53
0
75
54
0.76
0
69
52
1
0
66
47
0
0.2
115
84
0
0.4
98
70
0
0.6
89
63
0
0.8
82
57
0
1
79
57
0.066
0.066
125
89
0.175
0.175
93
72
0.284
0.284
83
61
0.392
0.392
75
55
0.5
0.5
70
53
* ύοέʔδͷλϒͷ෦෼ΛΧούΤϦΞͷτοϓαΠυͷॴʹ࣮૷͠·͢ɻ
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