QTS48T46096 DC-DC Converter Data Sheet
441-Watt @ 48Vin Quarter-Brick Bus Converter
6. Figure 3 shows the recommended airflow
voltage. Both input traces and the chassis ground
trace (if applicable) must be capable of conducting a
current of 1.5 times the value of the fuse without
opening. The fuse must not be placed in the
grounded input line, if any.
direction, unit orientation and temperature
variation of three paralleled units with 10%
current share accuracy. Please note that the
maximum power available will be reduced by
up to 10% due to current share accuracy.
(At 48 volts in, the maximum power available
would be 350 W X 3unit X 90% derating =
945 W)
In order for the output of the QTS48T46096
converter to be considered as SELV (Safety Extra
Low Voltage) or TNV-1, according to all IEC60950
based standards, one of the following requirements
must be met in the system design:
•
If the voltage source feeding the module is SELV
or TNV, the output of the converter may be
grounded or ungrounded.
•
If the voltage source feeding the module is ELV,
the output of the converter may be considered
SELV only if the output is grounded per the
requirements of the standard.
•
This information is provided for guidance only
and the user is responsible for any design
considerations regarding safety.
Thermal Considerations
The QTS48T46096 converter is designed for natural
or forced convection cooling.
The maximum
allowable output current of the converter is
determined by meeting the derating criteria for all
components used in the converter. For example,
the maximum semiconductor junction temperature is
not allowed to exceed 125 °C to ensure reliable long-
term operation of the converter. Contact Power-One
for the complete list of the derating criteria.
AIRFLOW DIRECTION
Figure 3. Three units in parallel with 50 V input voltage,
900 W output power, 70 °C ambient, and 200 LFM airflow.
Safety Considerations
The graph in Figure 4 and Figure 5 show the
maximum output current of the QTS48T46096
converter at different ambient temperatures under
both natural and forced (transverse airflow direction,
from pin 1 to pin 3) convection.
The QTS48T46096 converter features 1500 Volt DC
isolation from input to output. The input-to-output
resistance is greater than 10 MΩ. This converter is
provided with functional insulation between input and
output circuits according to all IEC60950 based
standards. Nevertheless, if the system using the
converter needs to receive safety agency approval,
certain rules must be followed in the design of the
system. In particular, all of the creepage and
clearance requirements of the end-use safety
requirements must be observed. These documents
include UL60950 - CSA60950-00 and EN60950,
although other or additional requirements may be
needed for specific applications.
For example, the QTS48T46096 operating at 48Vin,
70 °C can deliver up to 33.6A reliably with 200 LFM
forced air.
The QTS48T46096 converter has no internal fuse.
The external fuse must be provided to protect the
system from catastrophic failure. The fuse with a
rating not greater than 10 A is recommended. The
user can select a lower rating fuse based upon the
highest inrush transient at the maximum input
voltage and the maximum input current of the
converter, which occurs at the minimum input
ZD-02076 Rev 2.1
Page 5 of 7
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