User's Manual

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Note d’étude / Technical document : URDx– OTL 5635.1– 007 / 70 230 Edition 03
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3.1 HOW TO CONNECT TO A SIM CARD
Preliminary notes:
Figure 2: SIM Card signals
HiLo module provides the SIM signals on the board to board connector. A SIM card holder with 6 pins needs to
be adopted to use the SIM function. In this case, decoupling capacitors have to be added on SIM_CLK,
SIM_RST, VSIM and SIM_DATA signals as close as possible to the SIM card connector to avoid EMC issues.
Moreover, use ESD protection components to protect SIM card and module I/Os against Electro Static
Discharges. The following schematic show how to protect the SIM access for 6 pins connector.
1
1
2
2
3
3
5
5
4
4
CM1218
10pF 22pF 10pF10nF
SIM_DATA
VSIM
SIM_CLK
SIM_RST
33pF
VSIMSIM_CLK
SIM_RST
SIM_DATA
1
1
2
2
3
3
4
4
6
6
7
7
8
8
5
5
SIM connector
Figure 3: Protections: EMC and ESD components closed to the SIM
3.2 HOW TO CONNECT THE AUDIOS?
The HiLo module features one input audio path and one output audio path. The input path is single-end while
the output path is differential. In this following chapter examples of design will be given including protections
against EMC and ESD and some notes about the routing rules to follow to avoid the TDMA noise usually
present in this sensitive area of design.
3.2.1 Connecting microphone and speaker
The HiLo module can manage an external microphone (INTMIC_P) in single-end mode and an external speaker
(HSET_OUT_P / HSET_OUT_N) in differential mode. Thus, one speaker and one microphone can be