NZL5V6AXV3T1 Series
INFORMATION FOR USING THE SC-89 SURFACE MOUNT PACKAGE
MINIMUM RECOMMENDED FOOTPRINT FOR SURFACE MOUNTED APPLICATIONS
Surface mount board layout is a critical portion of the
total design. The footprint for the semiconductor packages
must be the correct size to insure proper solder connection
interface between the board and the package. With the
correct pad geometry, the packages will self align when
subjected to a solder reflow process.
0.53
0.53
1.10
Dimensions in Millimeters
0.50
SC-89
SC-89 POWER DISSIPATION
The power dissipation of the SC-89 is a function of the
SOLDERING PRECAUTIONS
drain pad size. This can vary from the minimum pad size
for soldering to a pad size given for maximum power
dissipation. Power dissipation for a surface mount device is
The melting temperature of solder is higher than the rated
temperature of the device. When the entire device is heated
to a high temperature, failure to complete soldering within
a short time could result in device failure. Therefore, the
following items should always be observed in order to
minimize the thermal stress to which the devices are
subjected.
• Always preheat the device.
• The delta temperature between the preheat and
soldering should be 100°C or less.*
• When preheating and soldering, the temperature of the
leads and the case must not exceed the maximum
temperature ratings as shown on the data sheet. When
using infrared heating with the reflow soldering
method, the difference shall be a maximum of 10°C.
• The soldering temperature and time shall not exceed
260°C for more than 10 seconds.
• When shifting from preheating to soldering, the
maximum temperature gradient shall be 5°C or less.
• After soldering has been completed, the device should
be allowed to cool naturally for at least three minutes.
Gradual cooling should be used as the use of forced
cooling will increase the temperature gradient and
result in latent failure due to mechanical stress.
• Mechanical stress or shock should not be applied
during cooling.
determined by T
, the maximum rated junction
J(max)
temperature of the die, R , the thermal resistance from
θJA
the device junction to ambient, and the operating
temperature, T . Using the values provided on the data
A
sheet for the SC-89 package, P can be calculated as
D
follows:
TJ(max) - TA
PD =
Rθ
JA
The values for the equation are found in the maximum
ratings table on the data sheet. Substituting these values
into the equation for an ambient temperature T of 25°C,
A
one can calculate the power dissipation of the device which
in this case is 240 milliwatts.
150°C - 25°C
PD =
= 240 milliwatts
525 °C/W
The 525 °C/W for the SC-89 package assumes the use of
the recommended footprint on a glass epoxy printed circuit
board to achieve a power dissipation of TBD milliwatts.
There are other alternatives to achieving higher power
dissipation from the SC-89 package. Another alternative
would be to use a ceramic substrate or an aluminum core
board such as Thermal Clad . Using a board material such
as Thermal Clad, an aluminum core board, the power
dissipation can be doubled using the same footprint.
* Soldering a device without preheating can cause excessive
thermal shock and stress which can result in damage to the
device.
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