Datasheet
PBSS4220V_2 © NXP B.V. 2009. All rights reserved.
Product data sheet Rev. 02 — 11 December 2009 4 of 13
NXP Semiconductors
PBSS4220V
20 V, 2 A NPN low V
CEsat
(BISS) transistor
6. Thermal characteristics
[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 cm
2
.
[3] Device mounted on a ceramic PCB, Al
2
O
3
, standard footprint.
[4] Reflow soldering is the only recommended soldering method.
Table 6. Thermal characteristics
Symbol Parameter Conditions Min Typ Max Unit
R
th(j-a)
thermal resistance from
junction to ambient
in free air
[1][4]
--410K/W
[2][4]
--250K/W
[3][4]
--140K/W
R
th(j-sp)
thermal resistance from
junction to solder point
--80K/W
FR4 PCB, standard footprint
Fig 2. Transient thermal impedance from junction to ambient as a function of pulse time; typical values
006aaa425
10
1
10
2
10
3
Z
th(j-a)
(K/W)
10
−1
10
−5
1010
−2
10
−4
10
2
10
−1
t
p
(s)
10
−3
10
3
1
0
duty cycle =
1
0.75
0.5
0.33
0.2
0.1
0.05
0.02
0.01