EM357 Mini Modules

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This document is subject to change without notice

Document No: 0011-00-07-00-000 (Issue H)

TRANSCEIVER IC

CEL’s MeshConnect EM357 Mini Modules use the Ember EM357 transceiver IC. This IC incorporates the RF

offering an excellent low cost high performance solution for all IEEE 802.15.4 / ZigBee applications. For more

information about the EM357 IC, visit www.silabs.com.

ANTENNA

CEL’s MeshConnect EM357 Mini Modules include an integrated Printed Circuit Board (PCB) trace antenna. An

optional configuration which uses a castellation pin on the module allows the user to connect an external antenna. The

ZICM357SP0 has been certified with the PCB trace antenna only while the ZICM357SP2 has been certified with the

PCB trace antenna and a Nearson half-wave dipole antenna (part number: S181AH-2450S) on a 4 inch cable using

the castellation pin of the module. Please refer to the document

ZICM357SP2-1C External Antenna Implementation

for details describing the requirements that must be followed to take advantage of the CEL certification.

The PCB antenna employs a topology that is compact and highly efficient. To maximize range, an adequate

ground plane must be provided on the host PCB. Correctly positioned, the ground plane on the host PCB will

contribute significantly to the antenna performance (it should not be directly under the module PCB Antenna).

The position of the module on the host board and overall design of the product enclosure contribute to antenna

performance. Poor design affects radiation patterns and can result in reflection, diffraction and/or scattering of

the transmitted signal.

For optimum antenna performance, the MeshConnect Modules should be mounted with the PCB trace antenna

overhanging the edge of the host board. To further improve performance, a ground plane should be placed on

the host board under the module, up to the antenna (a minimum of 1.5" x 1.5" is recommended). The installation

of an uninterrupted ground plane on a layer directly beneath the module will also allow you to run traces under

this layer. CEL can provide assistance with your PCB layout.

The following are some design guidelines to help ensure antenna performance:

• Never place the ground plane or route copper traces directly underneath the antenna portion of the module

• Never place the antenna close to metallic objects

• In the overall design, ensure that wiring and other components are not placed near the antenna

• Do not place the antenna in a metallic or metalized plastic enclosure

• Keep plastic enclosures 1cm or more away from the antenna in any direction

Under Industry Canada regulations, this radio transmitter may only operate using an antenna of a type and

maximum (or lesser) gain approved for the transmitter by Industry Canada. To reduce potential radio interference

to other users, the antenna type and its gain should be so chosen that the equivalent isotropically radiated power

(e.i.r.p.) is not more than that necessary for successful communication.

Conformément à la réglementation d'Industrie Canada, le présent émetteur radio peut fonctionner avec une

antenne d'un type et d'un gain maximal (ou inférieur) approuvé pour l'émetteur par Industrie Canada. Dans

le but de réduire les risques de brouillage radioélectrique à l'intention des autres utilisateurs, il faut choisir le

type d'antenne et son gain de sorte que la puissance isotrope rayonnée équivalente (p.i.r.e.) ne dépasse pas

l'intensité nécessaire à l'établissement d'une communication satisfaisante.

POWER AMPLIFIER

CEL’s MeshConnect EM357 High Power Module (ZICM357SP2) includes a Power Amplifier (PA). This PA

and reliable transmission for fewer nodes in a network. For the ZICM357SP2, Power Mode 2 with Power Setting

-2 is the maximum setting allowed for FCC compliance. Operating in Power Mode 3 at higher power settings may

damage the PA.