Ericsson Internal
PROD. SPECIFICATION MECHANICAL 2 (5)
Prepared (also subject responsible if other) No.
MICKAOV 5/1301-BMR 6401 Uen
Approved Checked Date Rev Reference
SEC/D (Julia You) See §1 2007-10-08 D
Pin Temperature Recommendations
Pin number 5 and 14 are chosen as reference locations for
the minimum pin (solder joint) temperature recommendations
since these will likely be the coolest solder joints during
reflow
SnPb Solder Processes
Minimum pin temperature: for SnPb solder processes, a pin
temperature (T
PIN
in excess of the solder meltin
temperature,
(T
L
, +183°C for Sn63Pb37) for more than 30 seconds, and a
peak temperature of +210°C is recommended to ensure a
reliable solder joint.
A maximum pin temperature of +225°C should be sufficient
for most applications but depending on type of solder paste
and flux system used on the host board, up to a
recommended maximum temperature of +245°C could be
used, provided that the products are kept in a controlled
environment (dry pack handling and storage) prior to
assembly.
Pb-free Solder Processes
For Pb-free solder processes, a pin temperature (T
PIN
) in
excess of the solder melting temperature (T
L
, +217 to +221 °C
for SnAgCu solder alloys) for more than 30 seconds, and a
peak temperature of +235°C on all solder joints is
recommended to ensure a reliable solder joint.
Maximum Product Temperature Requirements
Top of the product PCB near pin 9 or 10 are chosen as
reference locations for the maximum (peak) allowed product
temperature (T
PRODUCT
), since these will likely be the warmest
parts of the product during the reflow process.
SnPb Solder Processes
For conventional SnPb solder processes, the product is
qualified for MSL 1 according to IPC/JEDEC standard
J-STD-020C (no dry pack handling or controlled environment
required)
During reflow, T
PRODUCT
must not exceed +225 °C at any time.
If the products are handled as MSL 3 products, they can
withstand up to +260°C as in Pb-free solder processes.
Pb-free Solder Processes
For Pb-free solder processes, the product is qualified for
MSL 3 according to IPC/JEDEC standard J-STD-020C.
During reflow, T
PRODUCT
must not exceed +260 °C at any time.
Surface Mount Assembly and Repair
The solder bumps of the product require particular care
during assembly since the solder bumps are hidden between
the host board and the product’s PCB. Special procedures
are required for successful rework of these products.
Assembly
Automatic pick and place equipment should be used to
mount the product on the host board. The use of a vision
system, utilizing the fiducials on the bottom side of the
product, will ensure adequate accuracy. Manual mounting of
solder bump products is not recommended.
Note that the actual position of the pick up surface may vary
between variants within the product program and is not
necessarily in the center of the product outline.
If necessary, it is recommended to fine tune the solder print
aperture size to optimize the amount of deposited solder with
consideration to screen thickness and solder print capability.
Repair
For a successful repair (removal and replacement) of a solder
bump product, a dedicated rework system should be used.
The rework system should preferably utilize a bottom side
heater and a dedicated hot air nozzle to heat the solder
bumps to reflow temperature.
The product is an open frame design with a pick up surface
on a lar
e central component. This pick up surface can not be
used for removal with a vacuum nozzle since the component
solder joints may have melted during the removal reflow.
In order not to damage the product and nearby components
during removal and replacement with a new product, it is
recommended to use a double wall design of the hot air
nozzle to direct the air flow only to the edges of the product,
see ‘Assembly Information’ in the mechanical drawing.
Soldering Information — Hole Mounting
The hole mount version of the product is intended for manual
or wave soldering in plated through holes on the host board.
When wave soldering is used, the temperature on the pins is
specified to maximum +270 °C for maximum 10 seconds.
A maximum preheat rate of 4°C/s and a preheat temperature
of max of +150°C is suggested.
When solderin
b
hand, care should be taken to avoid direct
contact between the hot soldering iron tip and the pins for
more than a few seconds in order to prevent overheating.
A no-clean flux is recommended to avoid entrapment of
cleaning fluids in cavities inside the product or between the
product and the host board. The cleanin
residues ma
affect
long time reliability and isolation voltage.
PKR 2000A series
DC/DC converters, Input 18-36 V, Output up to 2 A/15 W
EN/LZT 146 352 R2C September 2007
© Ericsson Power Modules AB