User's Manual

GS2101M Low Power WiFi Module Data Sheet Package and Layout Guidelines
GS2101Mxx Recommended PCB Footprint and
GS2101M-DS-001270, Release 1.0 Confidential 53
– Antenna at edge of base board, not interior of base board
– Nothing conductive near antenna (e.g. battery, display, wire)
3. The 3 RF shield mounting holes and 2 test fixture alignment holes (circled in red in
Figure
4, page 51
) have exposed metal. These areas must not have metal on the customer board.
4. For best RF performance, we recommend:
– Using power(PWR) or the GND planes from module back to power supply.
– Isolating PWR/GND from high frequency or high current components. For example, a
notch in GND plane to isolate from host uC
– Using at least 3 vias when either power or GND changes layers. This applies particularly
at the module GND pins and at the VIN_3V3 pins.
– Providing a 10 uF capacitor at the VIN_3V3 pin and using 3 vias both sides of the
capacitor.
– Keep high speed signals away from RF areas of module.
5. For area under Module, other than antenna area, we recommend two options:
– No metal of any kind under module “not on any layer”
– Having full GND plane under module (layer 1 or layer 2) with no “HOT” vias under
module (over 100KHz) and may route signals below GND plane. Also no metal traces are
to be present in the circle, around shield and alignment holes (see datasheet). This option
is best for 2 layer boards. If GND plane is on layer 1, then use thermal relief pads for the
GND pins of the module footprint.
6. If any metal is present on layer 1, then extra thick solder mask under the module is required.
7. In performing SMT or manual soldering of the module to the base board, first align the row
of pins from #15 through #26 onto the base board and then match the other two rows.
In addition to the guidelines, note the following suggestions:
1. External Bypass capacitors for all module supplies should be as close as possible to the
module pins.
2. Never place the antenna very close to metallic objects.
3. External monopole antennas need a reasonable ground plane area for antenna efficiency.
4. Do not use a metallic or metalized plastic for the end product enclosure when using
on-board antenna.
5. If the module is enclosed in a plastic case, have reasonable clearance from plastic case to
on-board antenna.