Specifications

B
Rev 8 Apr.14 Proprietary and Confidential - Contents subject to change 73
B: Design Checklist
This chapter provides a summary of the design considerations
mentioned throughout this guide. This includes items relating to the
power interface, RF integration, thermal considerations, cabling
issues, and so on.
Note: This is NOT an exhaustive list of design considerations. It is expected
that you will employ good design practices and engineering principles in your
integration.
Table B-1: Hardware integration design considerations
Suggestion Section where discussed
Component placement
Protect the SIM socket so the SIM cannot be removed while the host is
powered up.
SIM implementation on
page 33
If an ESD suppressor is not used, allow space on the SIM connector for
series resistors in layout. (Up to 100 may be used depending on ESD
testing requirements).
SIM implementation on
page 33
Minimize RF cable losses as these affect performance values listed in
product specification documents.
RF connections on page 41
Antennas
Match the module/antenna coax connections to 50 mismatched
antenna impedance and cable loss negatively affect RF performance.
RF connections on page 41
If installing CDMA and UMTS modules in the same device, consider using
separate antennas for maximum performance.
Antenna and cabling on
page 42
Power
Make sure the power supply can handle the maximum current specified
for the module type.
Power consumption on
page 51
Limit the total impedance of VCC and GND connections to the SIM at the
connector to less than 1 (including any trace impedance and lumped
element componentsinductors, filters, etc.). All other lines must have a
trace impedance less than 2 .
SIM implementation on
page 33
Decouple the VCC line close to the SIM socket. The longer the trace
length (impedance) from socket to module, the greater the capacitance
requirement to meet compliance tests.
SIM implementation on
page 33
EMI/ESD
Investigate sources of localized interference early in the design cycle. Methods to mitigate decreased
Rx performance on page 44
Provide ESD protection for the SIM connector at the exposed contact
point (in particular, the CLK, VCC, IO, and RESET lines).
SIM implementation on
page 33