DocID025281 Rev 1

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HDMI2C1-6C1

Recommendation on PCB assembly

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5.2

Solder paste

1.

Use halide-free flux, qualification ROL0 according to ANSI/J-STD-004.

2.

“No clean” solder paste recommended.

3.

Offers a high tack force to resist component displacement during PCB movement.

4.

Use solder paste with fine particles: powder particle size 20-45 µm.

5.3

Placement

1.

Manual positioning is not recommended.

2.

It is recommended to use the lead recognition capabilities of the placement system, not

the outline centering.

3.

Standard tolerance of ± 0.05 mm is recommended.

4.

3.5 N placement force is recommended. Too much placement force can lead to

squeezed out solder paste and cause solder joints to short. Too low placement force

can lead to insufficient contact between package and solder paste that could cause

open solder joints or badly centered packages.

5.

To improve the package placement accuracy, a bottom side optical control should be

performed with a high resolution tool.

6.

For assembly, a perfect supporting of the PCB is recommended during solder paste

printing, pick and place and reflow soldering by using optimized tools.

5.4

PCB design preference

1.

To control the solder paste amount, closed vias are recommended instead of open

vias.

2.

The position of tracks and open vias in the solder area should be well balanced.

Symmetrical layout is recommended, in case any tilt phenomena caused by

asymmetrical solder paste amount due to the solder flow away.

5.5

Reflow profile

Note:

Minimize air convection currents in the reflow oven to avoid component movement.

250

0

50

100

150

200

240

210

180

150

120

90

60

30

300

270

-6°C/s

240-245 °C

2 - 3 °C/s

Temperature (°C)

-2 °C/s

-3 °C/s

Time (s)

0.9 °C/s

60 sec

(90 max)