NXP Semiconductors
BC637; BCP55; BCX55
60 V, 1 A NPN medium power transistors
10
3
duty cycle =
Z
th(j-a)
(K/W)
10
2
1.0
0.75
0.5
0.33
0.2
0.1
10
0.05
0.02
0.01
0
1
10
−5
10
−4
10
−3
10
−2
10
−1
1
10
10
2
006aaa815
10
3
t
p
(s)
FR4 PCB, standard footprint
Fig 7. Transient thermal impedance from junction to ambient as a function of pulse duration for SOT89;
typical values
10
3
Z
th(j-a)
(K/W)
10
2
006aaa090
duty cycle =
1
0.75
0.5
0.33
0.2
0.1
10
0.05
0.02
0.01
0
10
−4
10
−3
10
−2
10
−1
1
10
10
2
t
p
(s)
10
3
1
10
−5
FR4 PCB, mounting pad for collector 1 cm
2
Fig 8. Transient thermal impedance from junction to ambient as a function of pulse duration for SOT89;
typical values
BC637_BCP55_BCX55_7
© NXP B.V. 2007. All rights reserved.
Product data sheet
Rev. 07 — 25 June 2007
8 of 15
PHILIPS [ NXP SEMICONDUCTORS ]
