Ericsson Internal
E
EMAOLII
PRODUCT SPECIFICATION
6 (8)
Prepared (also subject responsible if other)
No.
30/1301-BMR 456 Uen
38
Technical Specification
BMR456 series Fully regulated AdvCahneckceed d Bus Converters
Approved
Date
Rev
Reference
1/28701-FGC 101 1823 revD February 2013
SEC/D (Julia You)
EZHIXZH
2013-02-06
F
© Ericsson AB
Input 36-75 V, Output up to 39 A / 468 W
Thermal Consideration
General
The product is designed to operate in different thermal
environments and sufficient cooling must be provided to
ensure reliable operation. For products mounted on a PWB
without a heat sink attached, cooling is achieved mainly by
conduction, from the pins to the host board, and convection,
which is dependant on the airflow across the product.
Increased airflow enhances the cooling of the product. The
Output Current Derating graph found in the output section for
each model provides the available output current vs. ambient
air temperature and air velocity at VI =53 V.
The product is tested on a 254 x 254 mm, 35 µm (1 oz),
16-layer test board mounted vertically in a wind tunnel with a
cross-section of 608 x 203 mm.
Definition of product operating temperature
The product operating temperature is used to monitor the
temperature of the product, and proper thermal conditions
can be verified by measuring the temperature at positions
P1, P2, P3 and P4. The temperature at these positions (TP1,
TP2, TP3, TP4) should not exceed the maximum temperatures
in the table below. The number of measurement points may
vary with different thermal design and topology.
Temperatures above maximum TP1, measured at the
reference point P1 (TP3 / P3 for base plate versions) are not
allowed and may cause permanent damage.
Position
P1
Description
Max temperature
TP1=125º C
PWB (reference point, open
frame)
P2
Opto-coupler
TP2=105º C
PWB (reference point for
base-plate version)
P3
TP3=125º C
P4
Primary MOSFET
TP4=125º C
For products with base plate used in a sealed box/cold wall
application, cooling is achieved mainly by conduction through
the cold wall. The Output Current Derating graphs are found in
the output section for each model. The product is tested in a
sealed box test set up with ambient temperatures 85, 55 and
25°C. See Design Note 028 for further details.