MIXERS - SMT
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7 - 425
For price, delivery, and to place orders, please contact Hittite Microwave Corporation:
20 Alpha Road, Chelmsford, MA 01824 Phone: 978-250-3343 Fax: 978-250-3373
Order On-line at www.hittite.com
Recommended SMT Attachment Technique
Preparation & Handling of the LM3 Millimeterwave Package for Surface Mounting
The HMC LM3 package was designed to be compatible with high
volume surface mount PCB assembly processes. The LM3 package
requires a speci c mounting pattern to allow proper mechanical
attachment and to optimize electrical performance at millimeterwave
frequencies. This PCB layout pattern can be found on each LM3
product data sheet. It can also be provided as an electronic drawing
upon request from Hittite Sales & Application Engineering.
Follow these precautions to avoid permanent damage:
Cleanliness: Observe proper handling procedures to ensure clean
devices and PCBs. LM3 devices should remain in their original
packaging until component placement to ensure no contamination or damage to RF, DC & ground contact areas.
Static Sensitivity: Follow ESD precautions to protect against ESD strikes.
General Handling: Handle the LM3 package on the top with a vacuum collet or along the edges with a sharp pair
of bent tweezers. Avoiding damaging the RF, DC, & ground contacts on the package bottom. Do not apply excess
pressure to the top of the lid.
Solder Materials & Temperature Pro le: Follow the information contained in the application note. Hand soldering is
not recommended. Conductive epoxy attachment is not recommended.
Solder Paste: Solder paste should be selected based on the user’s experience and be compatible with the metallization
systems used. See the LM3 data sheet Outline drawing for pin & ground contact metallization schemes.
Solder Paste Application: Solder paste is generally applied to the PCB using either a stencil printer or dot placement.
The volume of solder paste will be dependent on PCB and component layout and should be controlled to ensure
consistent mechanical & electrical performance. Excess solder may create unwanted electrical parasitics at high
frequencies.
Solder Re ow: The soldering process is usually accomplished in a re ow oven but may also use a vapor phase
process. A solder re ow pro le is suggested above.
Prior to re owing product, temperature pro les should be measured using the same mass as the actual assemblies.
The thermocouple should be moved to various positions on the board to account for edge and corner effects and
varying component masses. The nal pro le should be determined by mounting the thermocouple to the PCB at the
location of the device.
Follow solder paste and oven vendor’s recommendations when developing a solder re ow pro le. A standard pro le
will have a steady ramp up from room temperature to the pre-heat temperature to avoid damage due to thermal shock.
Allow enough time between reaching pre-heat temperature and re ow for the solvent in the paste to evaporate and the
ux to completely activate. Re ow must then occur prior to the ux being completely driven off. The duration of peak
re ow temperature should not exceed 15 seconds. Packages have been quali ed to withstand a peak temperature of
235°C for 15 seconds. Verify that the pro le will not expose device to temperatures in excess of 235°C.
Cleaning: A water-based ux wash may be used.
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TEMPERATURE (
0
C)
TIME (min)
HMC560LM3
v00.0705
GaAs MMIC FUNDAMENTAL
SMT MIXER, 24 - 40 GHz
