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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

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

high volume surface mount PCB assembly processes. The

LM3 package requires a specific mounting pattern to allow

proper mechanical attachment and to optimize electrical per-

formance at millimeterwave frequencies. This PCB layout pat-

tern 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 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.

HMC265LM3

GaAs MMIC SUB-HARMONIC

SMT MIXER, 20 - 31 GHz

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Information furnished by Analog Devices is believed to be accurate and reliable. However, no

responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other

rights of third parties that may result from its use. Specifications subject to change without notice. No

license is granted by implication or otherwise under any patent or patent rights of Analog Devices.

Trademarks and registered trademarks are the property of their respective owners.

For price, delivery, and to place orders: Analog Devices, Inc.,

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106

Phone: 781-329-4700 • Order online at www.analog.com

Application Support: Phone: 1-800-ANALOG-D