PCB recommendations

BAT30F3

6/10

Doc ID 16915 Rev 2

Figure 9.

Flip Chip tape and reel specification (dimensions in mm)

4

PCB recommendations

4.1

Design

For optimum electrical performance and highly reliable solder joints, STMicroelectronics

recommends the PCB design recommendations listed in Table 3.

Note:

A gold layer finishing on the PCB pad that is too thick (0.2 µm maximum) is not

recommended (low joint reliability).

User direction of unreeling

All dimensions in mm

4.0 ± 0.1

2.0 ± 0.05

2.0 ± 0.1

Ø 1.55 ± 0.05

0.43 ± 0.1

0.57 ± 0.05

0.20 ± 0.05

Table 3.

PCB design recommendations for solder bar pitch 400 µm

For NSMD PCB

non solder mask defined

Oblong pad: 370 x 180 µm

– Micro via SSBU allowed

– Micro via SBU to be avoided

– Micro via SBU filled (under qualification)

Track:

– Only one track per pad

– Maximum track width = 100 µm

Track layout must be symmetrical to the die axis (to homogenize stress

and welding attraction during reflow assembly)

For SMD PCB

solder mask defined

Oblong pad:

– Micro via SSBU allowed

– Micro via SBU to be avoided

– Micro via SBU filled (under qualification)

PCB Pad Finishing

Cu – Ni (2-6 µm) - Au (0.2 µm max)