Specifications

Cinterion
®
ALAS66A Hardware Interface Overview
2.2 GSM/UMTS/LTE Antenna Interface
33
 ALAS66A_HIO_v01.000a 2019-02-26
Confidential / Released
Page 28 of 51
2.2.2.2 Routing Examples
Interface to RF Connector
Figure 9 and Figure 10 show a sample connection of a module‘s antenna pad at the bottom
layer of the module PCB with an application PCB‘s coaxial antenna connector. Line impedance
depends on line width, but also on other PCB characteristics like dielectric, height and layer
gap. The sample stripline width of 0.50mm/0.75mm and the spaces of 0.35mm/0.3mm are only
recommended for an application with a PCB layer stack resembling the one of the ALAS66A
evaluation board, and with layer 2 as well as layer 3 cut clear. For different layer stacks the
stripline width will have to follow stripline routing rules, avoiding 90 degree corners and using
the shortest distance to the PCB’s coaxial antenna connector.
Figure 9: Routing to application‘s RF connector
Figure 10: Routing detail
G N D
G N D
Edge of module PCB
Stripline (50 ohms) on top
layer of evaluation board from
antenna pad to module edge
Width = 0.50 mm
E.g., U.FL antenna
connector
50 ohms microstrip line
G N D G N D
Ground connection
e.g.
ANT_
TRX1
RF track under module:
Line/space: 500/350μm
RF track outside module:
Line/space:
750/300μm
Module ĞĚŐĞ