HMC265LM3_06 Datasheet, PDF (8/8 Pages) Hittite Microwave Corporation – GaAs MMIC SUB-HARMONIC SMT MIXER, 20 - 31 GHz

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HMC265LM3
GaAs MMIC SUB-HARMONIC
SMT MIXER, 20 - 31 GHz
HMC265LM3 Recommended SMT Attachment Technique
Preparation & Handling of the LM3 Millimeterwave Package for Surface Mounting
The HMC LM3 package was designed to be compatible with ²²⁵
high volume surface mount PCB assembly processes. The ₂₀₀
LM3 package requires a specific mounting pattern to allow
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proper mechanical attachment and to optimize electrical per- ¹⁷⁵
formance at millimeterwave frequencies. This PCB layout pat- 150
tern can be found on each LM3 product data sheet. It can also
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be provided as an electronic drawing upon request from Hittite
Sales & Application Engineering.
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Follow these precautions to avoid permanent damage:
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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.
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TIME (min)
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 pres-
sure to the top of the lid.
Solder Materials & Temperature Profile: 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 Reflow
The soldering process is usually accomplished in a reflow oven but may also use a vapor phase process. A solder
reflow profile is suggested above.
Prior to reflowing product, temperature profiles 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 final profile 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 reflow profile. A standard profile
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 reflow for the solvent in the paste to evaporate and the
flux to completely activate. Reflow must then occur prior to the flux being completely driven off. The duration of peak
reflow temperature should not exceed 15 seconds. Packages have been qualified to withstand a peak temperature of
235°C for 15 seconds. Verify that the profile will not expose device to temperatures in excess of 235°C.
Cleaning
A water-based flux wash may be used.
For price, delivery, and to place orders, please contact Hittite Microwave Corporation:
20 Alpha Road, Chelmsford, MA 01824 Phone: [phone] Fax: [phone]
Order On-line at www.hittite.com
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