NXP Semiconductors
PBSS4350SPN
50 V, 2.7 A NPN/PNP low VCEsat (BISS) transistor
6. Thermal characteristics
Table 7. Thermal characteristics
Symbol Parameter
Per transistor
Rth(j-a)
thermal resistance from
junction to ambient
Rth(j-sp)
thermal resistance from
junction to solder point
Per device
Rth(j-a)
thermal resistance from
junction to ambient
Conditions
in free air
Min Typ Max Unit
[1] -
-
227 K/W
[2] -
-
144 K/W
[3] -
-
87
K/W
-
-
40
K/W
in free air
[1] -
-
167 K/W
[2] -
-
104 K/W
[3] -
-
63
K/W
[1] Device mounted on an FR4 PCB, single-sided copper, tin-plated and standard footprint.
[2] Device mounted on an FR4 PCB, single-sided copper, tin-plated, mounting pad for collector 1 cm2.
[3] Device mounted on a ceramic PCB, Al2O3, standard footprint.
103
Zth(j-a)
(K/W)
duty cycle =
102
1.0
0.75
0.5
0.33
0.2
0.1
10
0.05
0.02
0.01
0
1
006aaa809
10−1
10−5
10−4
10−3
10−2
10−1
1
10
102
103
tp (s)
FR4 PCB, standard footprint
Fig 2. Per transistor: Transient thermal impedance from junction to ambient as a function of pulse duration;
typical values
PBSS4350SPN_1
Product data sheet
Rev. 01 — 5 April 2007
© NXP B.V. 2007. All rights reserved.
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