Tyco Electronics Corp. 5
Data Sheet SE014S110 Power Module; dc-dc Converter:
January 2000 48 Vdc Input, 110 Vdc Output, 14 W
Test Configurations
8-652(C).a
Note: Input reflected-ripple current is measured with a simulated
source impedance of 0.5 µH. Capacitor C
S
offsets possible
battery impedance. Voltage ripple is measured at the input ter-
minals of the module.
Figure 1. Input Reflected-Ripple Test Setup
8-653(C)
Note: All measurements are taken at the module terminals. When
socketing, place Kelvin connections at module terminals to
avoid measurement errors due to socket contact resistance.
Figure 2. Output Voltage and Efficiency
Measurement Test Setup
Design Considerations
Output Capacitor
An external output capacitor is required for operation of
the power module. The output capacitor should be
mounted as close as possible to the module output
pins. Capacitor and ESR values are shown in the Out-
put Specifications table. The voltage rating of the out-
put capacitor should be at least 160 V.
Input Capacitor
The power module should be connected to a low
ac-impedance input source. Source impedances of
greater than 12 µH may affect the stability of the power
module. When the source impedance exceeds 12 µH,
mount a 47 µF electrolytic capacitor (ESR = 0.2
Ω
at
100 kHz, T
A
= 25 °C) as close as possible to the mod-
ule input pins.
An external input capacitor is not required if the input
source impedance is less than 12 µH.
Safety Considerations
For safety-agency approval of the system in which the
power module is used, the power module must be
installed in compliance with the spacing and separation
requirements of the end-use safety agency standard,
i.e.,
UL
1950 and
CSA
C22.2 No. 950-95.
If the input source is non-SELV (ELV or a hazardous
voltage greater than 60 Vdc and less than or equal to
75 Vdc), for the module's output to be considered
meeting the requirements of safety extra-low voltage
(SELV), all of the following must be true:
■
The input source is to be provided with reinforced
insulation from any other hazardous voltages, includ-
ing the ac mains.
■
One V
I
pin and one V
O
pin are to be grounded or both
the input and output pins are to be kept floating.
■
The input pins of the module are not operator acces-
sible.
■
Another SELV reliability test is conducted on the
whole system, as required by the safety agencies, on
the combination of supply source and the subject
module to verify that under a single fault, hazardous
voltages do not appear at the module's output.
Note:
Do not ground either of the input pins of the
module without grounding one of the output
pins. This may allow a non-SELV voltage to
appear between the output pins and ground.
The power module has extra-low voltage (ELV) outputs
when all inputs are ELV.
The input to these units is to be provided with a maxi-
mum 5 A normal-blow fuse in the ungrounded lead.
L
0.5 µH
220 µF
IMPEDANCE < 0.1 Ω
@ 20 °C, 100 kHz
VI(+)
VI(–)
BATTERY
CS
Vripple
+
–
VI(+)
VI(–)
V
O(+)
V
O(–)
IO
CONTACT
RESISTANCE
CONTACT AND
DISTRIBUTION LOSSES
LOAD
33 µF
II
SUPPLY
η
VO(+) VO(–)–[] IO
VI(+) VI(–)–[] II
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100×= %
