ADMP621

Data Sheet

PCB DESIGN AND LAYOUT

The recommended PCB land pattern for the ADMP621 must

be laid out to a 1:1 ratio to the solder pads on the microphone

package, as shown in Figure 19. Avoid applying solder paste to the

sound hole in the PCB. A suggested solder paste stencil pattern

layout is shown in Figure 20.

The response of the ADMP621 is not affected by the PCB hole

size as long as the hole is not smaller than the sound port of the

microphone (0.25 mm, or 0.010 inch, in diameter). A 0.5 mm

to 1 mm (0.020 inch to 0.040 inch) diameter for the hole is

recommended. Take care to align the hole in the microphone

package with the hole in the PCB. The exact degree of the

alignment does not affect the microphone performance as long

as the holes are not partially or completely blocked.

0.40 × 0.60 (4×)

(0.30)

0.90

(0.30)

ø1.70

3.80

(0.30)

0.35

2.80

2× R0.10

(0.30)

0.35

2.05

0.70

ø1.10

(1.000)

(0.550)

CENTER LINE

Figure 19. Recommended PCB Land Pattern Layout

1.45

0.9

2.45

0.7

1.525

1.000

0.35

1.849

1.849

1.498

0.205 WIDE

0.248 × 0.498 (2×)

0.248 × 1.148 (2×)

0.248 × 0.948 (2×)

1.498 × 0.248

0.398 × 0.298 (4×)

0.362 CUT (3×)

1.17

24°

24°

0.375

CENTER

LINE

Figure 20. Suggested Solder Paste Stencil Pattern Layout

Rev. 0 | Page 12 of 16