LISA-U1 series - System Integration Manual
3G.G2-HW-10002-3
Preliminary
Design-In
Page 93 of 125
Additional guidelines for products marked with the FCC logo - United States only
LISA-U1 series modules can only be used with a host antenna circuit trace layout according to these guidelines; a
host system designer must follow the guidelines to keep the original Grant of LISA-U1 series modules.
Strict compliance to the layout reference design already approved (described in the following guidelines)
is required to ensure that only approved antenna shall be used in the host system.
If in a host system there is any difference from the trace layout already approved, it requires a Class II
permissive change or a new grant as appropriate as FCC defines.
Compliance of this device in all final host configurations is the responsibility of the Grantee.
The approved reference design for LISA-U1 series modules has a structure of four layers described in the
following.
The Layer 1 (top layer, see Figure 48) provides a micro strip line to connect the
ANT
pin of the LISA-U1 series
module to the antenna connector. The
ANT
pin of the LISA-U1 series module must be soldered on the designed
pad which is connected to the antenna connector by a micro strip. The characteristics of the micro strip line
(coplanar wave guide) are the following:
Thickness = 0.035 mm
Width = 0.26 mm
Length = 7.85 mm
Gap (signal to GND) = 0.5 mm
The micro strip line must be designed to achieve 50
Ω
characteristic impedance: the dimensions of the micro
strip line must be calculated in a host system according to PCB characteristics provided by PCB manufacturer.
Pad designed for the ANT pin
Antenna connector
Microstrip line
Figure 48: Layer 1 (top layer) of u-blox approved interface board for LISA-U1 series modules
The thickness of the dielectric (FR4 Prepreg 1080) from Layer 1 (top layer) to Layer 2 (inner layer) is 0.27 mm.
The Layer 2 (inner layer, described in Figure 49) provides a GND plane.
Layer 2 thickness is 0.035 mm.
