DocID025558 Rev 2

9/13

ESDAVLC8-1BT2Y

Recommendation on PCB assembly

13

3

Recommendation on PCB assembly

3.1

Stencil opening design

1.

General recommendation on stencil opening design

a)

Stencil opening dimensions: L (Length), W (Width), T (Thickness).

Figure 21. Stencil opening dimensions

b)

General design rule

Stencil thickness (T) = 75 ~ 125 µm

2.

Reference design

a)

Stencil opening thickness: 100 µm

b)

Stencil opening for central exposed pad: Opening to footprint ratio is 50%.

c)

Stencil opening for leads: Opening to footprint ratio is 90%.

Figure 22. Recommended stencil window position in mm (inches)

L

T

W

Aspect Ratio

W

T

-----

1.5

≥

=

Aspect Area

LW

×

2T L

W

+

()

----------------------------

0.66

≥

=

Lead footprint on PCB

Stencil window opening

0.55

(0.022)

0.40

(0.016)

0.522

(0.021)

0.014

(0.00055)

0.014

(0.00055)