Datasheet

2004 Dec 14 5
NXP Semiconductors Product data sheet
NPN high-voltage transistors BF620; BF622
THERMAL CHARACTERISTICS
Notes
1. Device mounted on a printed-circuit board, single-sided copper, tin-plated and standard footprint.
2. Device mounted on a printed-circuit board, single-sided copper, tin-plated and mounting pad for collector 1 cm
2
.
3. Device mounted on a printed-circuit board, single-sided copper, tin-plated and mounting pad for collector 6 cm
2
.
SYMBOL PARAMETER CONDITIONS VALUE UNIT
R
th(j-a)
thermal resistance from junction to
ambient
in free air
note 1 250 K/W
note 2 156 K/W
note 3 113 K/W
R
th(j-s)
thermal resistance from junction to
soldering point
30 K/W
006aaa235
10
−5
1010
−2
10
−4
10
2
10
−1
t
p
(s)
10
−3
10
3
1
10
2
10
10
3
Z
th
(K/W)
1
(6)
(7)
(8)
(9)
(10)
(1)
(5)
(4)
(3)
(2)
Fig.3 Transient thermal impedance as a function of pulse time; typical values.
(1) δ = 1.
(2) δ = 0.75.
(3) δ = 0.5.
(4) δ = 0.33.
(5) δ = 0.2.
(6) δ = 0.1.
(7) δ = 0.05.
(8) δ = 0.02.
(9) δ = 0.01.
(10) δ = 0.
Mounted on FR4 printed-circuit board; standard footprint.