Nexperia
BC817K series
45 V, 500 mA NPN general-purpose transistors
BC817K_SER All information provided in this document is subject to legal disclaimers. © Nexperia B.V. 2018. All rights reserved.
Product data sheet Rev. 2 — 6 March 2018
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6 Thermal characteristics
Table 7. Thermal characteristics
Symbol Parameter Conditions Min Typ Max Unit
[1]
- - 358 K/W
[2]
- - 218 K/W
[3]
- - 218 K/W
R
th(j-a)
thermal resistance from junction
to ambient
in free air
[4]
- - 162 K/W
R
th(j-sp)
thermal resistance from junction
to solder point
- - 60 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 cm
2
.
[3] Device mounted on an FR4 PCB; 4-layer copper; tin-plated and standard footprint.
[4] Device mounted on an FR4 PCB; 4-layer copper; tin-plated; mounting pad for collector 1 cm
2
.
aaa-027358
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(j-a)
(K/W)
1
duty cycle = 1
0
0.01
0.02
0.75
0.50
0.33
0.20
0.10
0.05
FR4 PCB; single-sided copper; tin-plated and standard footprint
Figure 3. Transient thermal impedance from junction to ambient as a function of pulse
duration; typical values
aaa-027359
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(j-a)
(K/W)
1
duty cycle = 1
0
0.01
0.02
0.75
0.50
0.33
0.20
0.10
0.05
FR4 PCB; single-sided copper; tin-plated; mounting pad for collector 1 cm
2
Figure 4. Transient thermal impedance from junction to ambient as a function of pulse
duration; typical values
