User's Manual Part 1

MC75 Hardware Interface Description

Strictly confidential / Draft

MC75_V00.190a Page 60 of 91 15.02.2005

4.2 Antenna Pad

The antenna can be soldered to the pad, or attached via contact springs. For proper

grounding connect the antenna to the ground plane on the bottom of MC75 which must be

connected to the ground plane of the application.

When you decide to use the antenna pad take into account that the pad has not been

intended as antenna reference point (ARP) for the Siemens MC75 type approval. The

antenna pad is provided only as an alternative option which can be used, for example, if the

recommended Hirose connection does not fit into your antenna design.

Also, consider that according to the GSM recommendations TS 45.005 and TS 51.010-01 a

50 connector is mandatory for type approval measurements. This requires GSM devices

with an integral antenna to be temporarily equipped with a suitable connector or a low loss

RF cable with adapter.

To prevent damage to the module and to obtain long-term solder joint properties you are

advised to maintain the standards of good engineering practice for soldering.

MC75 material properties:

MC75 PCB: FR4

Antenna pad: Gold plated pad

4.2.1 Suitable Cable Types

For direct solder attachment, we suggest to use the following cable types:

• RG316/U 50 Ohm coaxial cable

• 1671A 50 Ohm coaxial cable

Suitable cables are offered, for example, by IMS Connector Systems. For further details and

other cable types please contact http://www.imscs.com