USB-KW019032 Freescale USB Dongle Development Board , User’s Guide, Rev. 0, 10/2015
Freescale Semiconductor, Inc.
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PCB manufacturing specifications
CAUTION
The USB-KW019032 development board contains high-frequency
sub-GHz RF circuitry. The RF component placement, line geometries and
layout, and spacing to the ground plane are critical parameters. The 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
). The current board thickness is 64 mils.
For a 1 dB improvement, change the thickness to 32 mils (change the
intermediate dialectic on inner layer B-Target to 8 mils). The board may
become fragile.
Figure 19. USB-KW019032 PCB stackup cross-section (four layers)
•
Solder mask is required
•
Silk screen is required
5.2
Panelization
The panel size can be adjusted according to production volume.
5.3
Materials
The PCB composite materials must meet the following requirements:
•
Laminate: the base material (laminate) must be FR4. If the laminate material is changed, the RF
electrical characteristics change, and degrade the RF performance.
•
Copper foil
— The top and bottom copper layers must be 1 oz. copper
— Interior layers must be 1 oz. copper
•
Plating: the whole pad plating must be made by Hot Air Leveling (HAL)
5.4
Solder mask
The solder mask must meet the following requirements:
•
Solder mask type must be Liquid Film Electra EMP110 or equivalent
•
Solder mask thickness must be 10 – 30 µm
