CMA3000 Assembly Instructions

Note that the stencil openings should always be matched to the selected PWD pad design and

solder paste type for the optimal solder paste release. Furthermore, the stencil material and

method of forming those have an effect on solder paste release.

5.4

Paste Printing

The paste printing speed should be adjusted according to the solder paste specifications. Care

should be taken during paste printing in order to ensure correct paste amount, shape, position, and

other printing characteristics. Neglecting any of these can cause open solder joints, bridging,

solder balling, or other unwanted soldering results.

5.5

Component Picking

The CMA3000 component can be picked from the carrier tape using vacuum nozzles. Pick up

nozzles are available in various sizes and shapes to suit a variety of different component

geometries. It is recommended to that different pick up nozzles are tested to find the best one

suited for the purpose. The polarity of the part on tape is presented in section 4.1.

In case manual handling of the CMA3000 component is required, special attention should be paid

on the handling procedures. Delicate handling is a necessity as exposed silicon and glass surfaces

on the CMA3000 component are very sensitive to mechanical handling. Handling with metallic

tweezers should be forbidden. However, manual handling is not recommended.

5.6

Component Placement

The CMA3000 components must be placed onto PWB accurately according to their geometry.

Reflowable solder spheres provide self-alignment for the component, which will help with accurate

positioning. Positioning the packages manually is not recommended.

Placement can be done with typical automatic component pick & place machinery capable of

placing similar sized components. Recognition of the packages automatically by a vision system

enables correct centering of the packages. The Z placement should be carefully controlled as too

high force or overdriving during the component placement may damage the component and cause

misalignment. Maximum assembly force is 4 N. Locally the mounting pressure should not exceed 1

MPa.

5.7

Reflow Soldering

A forced convection reflow oven is recommended to be used for soldering CMA3000 components.

The reflow profile used for soldering the CMA3000 should always follow the solder paste

manufacturer's specifications and recommended profile. The ramp-up rate should typically be less

than 3°C/second. The reflow maximum peak temperature (measured from the component body)

should not exceed 260°C and the minimum temperature (measured from the solder joints) should

be higher than 230°C. The ramp down rate should be 6°C/second max. Figure 10 presents a

general forced convection reflow solder profile with the typical phases of a reflow process. Please

refer to IPC/JEDEC J-STD-020C table 5-2 and figure 5-1 for details. Recommended max number

of reflow cycles is 3.

Subject to changes

TN68

11/18

Rev.09

PRELIMINARY

VTI Technologies Oy

www.vti.fi