User's Manual

BT900-Sx Hardware Integration Guide
Intelligent BTv4.0 Dual Mode Module
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32 CONN-HIG-BT900
6.3 PCB Layout on Host PCB for BT900-SA
6.3.1 Antenna keep-out on host PCB
The BT900-SA has an integrated chip antenna and its performance is sensitive to host PCB. It is
critical to locate the BT900-SA on the edge of the host PCB (or corner) to allow the antenna to
radiate properly. Refer to guidelines in section PCB land pattern and antenna keep-out area for
BT900-SA. Some of those guidelines repeated below.
 Ensure there is no copper in the antenna keep-out area on any layers of the host PCB. Keep
all mounting hardware and metal clear of the area to allow proper antenna radiation.
 For best antenna performance, place the BT900-SA module on the edge of the host PCB,
preferably in the corner with the antenna facing the corner.
 The BT900 development board has the BT900-SA module on the edge of the board (not in
the corner). The antenna keep-out area is defined by the BT900 development board
which was used for module development and antenna performance evaluation is shown in
Figure 9, where the antenna keep-out area is ~4.2 mm wide, 34.2 mm long; with PCB
dielectric (no copper) height 1.0 mm sitting under the BT900-SA antenna.
 A different host PCB thickness dielectric will have small effect on antenna.
 The antenna-keep-out defined in Host PCB Land Pattern and Antenna Keep-out for
BT900-SA applies when the BT900-SA is placed in the corner of the host PCB. When BT900-SA
cannot be placed as such, it must be placed on the edge of the host PCB and the antenna
keep out must be observed. An example is shown in Figure 9.
Figure 9: Antenna keep-out area (shown in red), corner of the BT900 development board for BT900-SA
module.
Antenna Keepout
BT900-SA module