SimTech SIMCom SIM5360-PCIE Series, Проектирование аппаратного обеспечения

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Smart Machine Smart Decision
SIM5360-PCIE_Hardware_Design
18
2015-01-22
Figure 4: SIM Card Holder Reference Circuit
SIM card circuit is susceptible to be interfered, causing the SIM card failure or some other issues, so it is
strongly recommended to follow these guidelines while designing:
 Make sure that SIM card holder should stay away from GSM antenna while in PCB layout;
 SIM traces should keep away from RF lines 、 VBAT and high-speed signal lines, and the shorter the
better;
 Keep good connectivity between SIM holder GND and module GND;
 It is recommended to do some protection on USIM_CLK to keep away from interference;
 Recommended to place a 1uF capacitor on USIM_VDD line and keep close to the holder;
 Place some TVS, the parasitic capacitance should not exceed 50pF, and cascade 51Ohm resistor to
enhance ESD protection.
4.5. PCM Interface
SIM5360-PCIE provides hardware PCM interface for external codec. The PCM interface enables
communication with an external codec to support hands-free applications. SIM5360-PCIE PCM interface can
be used in two modes: the default mode is auxiliary PCM (8 KHz short sync mode at 2048 KHz PCM CLK);
the other mode is primary PCM (8 KHz long sync mode at 128 KHz PCM CLK). In short-sync (primary PCM)
mode, SIM5360-PCIE can be a master or a slave. In long-sync (auxiliary PCM) mode, SIM5360-PCIE is
always a master. SIM5360-PCIE also supports 3 kinds of coding formats: 8 bits (u-law or A-law) and 16 bits
(linear).
Table 9: PCM Specification
Characteristics Specification
Line Interface Format Linear or 8 bits (
u
-law or A-law)
Data length 16bits or
8 bits
PCM Clock/Sync Source Master or a slave Mode(2048 KHz ) / Master Mode(128 KHz )
PCM Clock Rate 2048 KHz / 128Khz
PCM Sync Format Short sync/Long sync both support