SCA3000 Assembly Instructions

Figure 8. Typical convection reflow soldering phases and profile.

The process window for lead-free soldering is narrower than for traditional eutectic SnPb solders.

Thus, caution has to be taken care when adjusting the reflow profiles. The reflow profile should be

measured using a thermo-couple measurement system. It is recommended that at least three

thermo-couples are used, depending on the application. As a general guide, one thermo-couple

should be placed under a component having the largest thermal mass, one next to the smallest

component, one should be in contact with SCA3000 component's solder joint, and others to the

appropriate spots on a circuit board, e.g. corner, center, bottom of the board etc. The reflow profile

should be adjusted according to the measured data so that each solder joint experiences an

optimal reflow profile. The temperature gradient should be as small as possible across the

circuit board and the components. Extreme caution has to be taken if the circuit board

contains components with vastly different thermal masses.

5.8

Moisture sensitivity level (MSL) classification

The Moisture Sensitivity Level of the SCA3000 component is Level 3 according to the IPC/JEDEC

J-STD-020C. The part is delivered in a dry pack. The manufacturing floor time (out of bag) at the

customer’s end is 168 hours. Maximum soldering peak temperature for the SCA3000 is

260

°C/40sec, measured from the package body.

5.9

Inspection

Optical and visual inspection of solder joints can be done only partly, since the solder joints are

located underneath the component itself. Therefore inspection of the solder joints with conventional

AOI (automatic optical inspection) system is not recommended. Figure 9 show photos of how the

soldered component on PWB looks from different directions.

VTI Technologies Oy

Subject to changes

10/15

www.vti.fi

TN54

Rev.C