PCB design
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This document is the sole and exclusive property of WAVECOM. Not to be distributed or divulged
without prior written agreement.
WM_PRJ_Q24NG_PTS_002-001 June
2006
6 PCB design
6.1 General design rules
Clocks and other high frequency digital signals (e.g parallel and serial
buses) should be routed as far as possible from the Q24NG analog signals.
If the application design makes it possible, all analog signals should be
separated from digital signals by a ground line on the PCB.
It is recommended to protect clock signals with a ground belt.
Refer to the following sections for other constraints:
•
3.1.3 for the Power Supply,
•
3.2.6 for the SIM interface,
•
3.3.2.4 for the audio interface.
6.2 Design rules for application manufacturing
Warning:
The Wireless CPU Q24NG sub-series does not support any reflow
soldering.
6.3
Recommendation for lead free soldering
In order to maintain the RoHS status of the module, Wavecom
recommend, for the assembly of the module on the mother board and the
assembly of RF cable on the Module the use of
lead free solder wire and
flux.
For example:
o
Solder Wire: Kester 245 Cored 58 (Sn96.5Ag3Cu0.5)
o
Flux: Kester 952-D6.
6.4 Power supply
