Freescale USB Development Board USB-KW40Z User’s Guide, Rev. 0, 10/2015

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Freescale Semiconductor, Inc.

PCB manufacturing specifications

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PCB data:

— USB-KW40Z size: Approximately 18.5x 61.4 mm (0.73 x 2.42 inches)

— USB-KW40Z final thickness (Cu/Cu): 1.57 mm (0.62 inches) +/- 10% (excluding solder mask)

Table 3 defines some of the layers of the completed PCB. The artwork identification refers to the name of

the layer in commonly used terms.

IMPORTANT: The USB-KW40Z development board contains high frequency 2.4 GHz RF circuitry. As

a result, RF component placement, line geometries and layout, and spacing to the ground plane are critical

parameters. Therefore, BOARD STACKUP GEOMETRY IS CRITICAL. Dielectric and copper

thicknesses and spacing must not be changed; follow the stackup information provided with the reference

design (see Figure 19) information provided with the reference design.

Figure 19. USB-KW40Z PCB stackup cross-section (four layer)

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Solder mask is required

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Silk screen is required

5.2

Panelization

The panel size can be negotiated depending on production volume.

5.3

Materials

The PCB composite materials must meet the following requirements:

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Laminate—the base material (laminate) must be FR4. If the laminate material is changed, the RF

electrical characteristics may change and degrade RF performance.

Table 3. USB-KW40Z layer by layer overview

Layer

Artwork Identification

File Name

1

Silkscreen Top

PSS.art

2

Top Layer Metal

L1_PS.art

3

Ground Layer

L2_GND.art

4

Signal Layer

L3_INT_1.art

5

Bottom Layer Metal

L4_SS.art

6

Silkscreen Bottom

SSS.art