NXP Semiconductors
BC640; BCP53; BCX53
80 V, 1 A PNP medium power transistors
6. Thermal characteristics
Table 7.
Symbol
R
th(j-a)
Thermal characteristics
Parameter
thermal resistance from
junction to ambient
BC640
BCP53
BCX53
Conditions
in free air
Min
Typ
Max
Unit
-
-
-
-
-
-
-
-
-
-
-
-
150
190
125
230
135
95
K/W
K/W
K/W
K/W
K/W
K/W
R
th(j-sp)
thermal resistance from
junction to solder point
BC640
BCP53
BCX53
-
-
-
-
-
-
40
17
20
K/W
K/W
K/W
[1]
[2]
[3]
Device mounted on an FR4 PCB, single-sided copper, tin-plated and standard footprint.
Device mounted on an FR4 PCB, single-sided copper, tin-plated, mounting pad for collector 1 cm
2
.
Device mounted on an FR4 PCB, single-sided copper, tin-plated, mounting pad for collector 6 cm
2
.
10
3
Z
th(j-a)
(K/W)
10
2
duty cycle =
1
0.5
0.2
10
0.1
0.05
0.02
0.01
1
0
0.75
0.33
006aaa222
10
−1
10
−5
10
−4
10
−3
10
−2
10
−1
1
10
10
2
t
p
(s)
10
3
FR4 PCB, standard footprint
Fig 4. Transient thermal impedance from junction to ambient as a function of pulse duration for SOT54;
typical values
BC640_BCP53_BCX53_8
© NXP B.V. 2008. All rights reserved.
Product data sheet
Rev. 08 — 22 February 2008
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