7 Lifetime expectancy depends on
stress by temperature difference
¡
Regarding lifetime expectancy design of solder joint, following
contents must be considered.
It must be careful that the soldering joint is stressed by tempera-
ture rise and down which is occurred by self-heating and ambient
temperature change.
The stress is accelerated by thermal-cycling, therefore the tem-
perature difference should be minimized as much as possible if
temperature rise and down is occurred frequently.
¡
Product lifetime expectancy depends on the aluminum base plate
central temperature difference (
D
Tc) and number of cycling in a
day is shown in Fig.7.1.
If the aluminum base plate center part temperature changes fre-
quently by changing output load factor etc., the above the lifetime
expectancy design should be applied as well.
Please contact us for details.
0
5
10
25
30
35
40
45
50
55
60
65
70
1time ON/OFF /1day
2times ON/OFF /1day
3times ON/OFF /1day
4times ON/OFF /1day
5times ON/OFF /1day
The aluminum base plate central temperature difference
D
Tc [
C
]
Lifetime expectancy [years
]
Fig.7.1 Lifetime expectancy against rise/fall temperature difference
Application manuals available at our website.
Recommended external components are also introduced for your
reference.
8 Others
8.1 Medical electrical equipment
¿
TUNS1200F
¡
TUNS1200F fit 2MOOP
1MOOP
Safety GND
primary secondary
2MOOP
Fig.8.1 Medical Isolation Grade
¡
It is required to have fuses on both line then applying for medical
approvals.
¡
Select the decoupling capacitor CY of which the leakage current
does not exceed 0.5mA.
Heatsink
Load
FG
Co
+
+
R
C1
F1
FG
AC IN
FG
TFR1
CY
C3
C2
+BC
+S
-BC
-S
Cbc
AC1
AC2
+VOUT
-VOUT
Noise
filter
F2
TUNS1200F
Fig.8.2 External components when applying for medical approvals
AC-DC Power Supplies Bus Converter.Power Module Type TUNS300F, TUNS500F, TUNS700F, TUNS1200F
Instruction Manual
TUNS-31
July 27, 2020
