DA14531MOD

Final

Datasheet

Revision 3.1

31-May-2021

CFR0011-120-00

22 of 32

© 2021-2021 Dialog Semiconductor

9

Soldering

parameters such as the thickness of the stencil, the pads solder paste aperture, the solder paste

characteristics, the reflow soldering profile, size of the PCB, etc.

The volume of solder paste applied to the board is mainly determined by the aperture size and stencil

thickness. An initial solder paste aperture for the pads is provided on the solder paste layer of the

PCB footprint. This aperture is modified by the assembly process experts according to stencil

thickness, solder paste and available assembly equipment.

The solder profile depends on the solder paste type used. For example, the soldering profile of a

lead-free solder paste, Sn3Ag0.5Cu with no clean Flux (ROL0) and Solder Powder Type 4, is

presented below.

No clean flux is recommended because washing must not be applied after assembly to avoid that

moisture is trapped under the shield.

Figure 21: Recommended Reflow Profile for Lead Free Solder

Table 11: Reflow Profile Specification

Statistic name

Low limit

High limit

Units

Slope1 (Target=2.0) Between 30.0 and 70.0

1

3

Degrees/Second

Slope2 (Target=2.0) Between 70.0 and 150.0

1

3

Degrees/Second

Slope3 (Target=-2.8) Between 220.0 and 150.0

-5

-0.5

Degrees/Second

Preheat time 110-190

C

60

120

Seconds

Time above reflow @220

C

30

65

Seconds

Peak temperature

235

250

Degrees Celsius

Total time above @235

C

10

30

Second