SIM5218E Hardware Design
SIM5218E_ Hardware Design_V1.06
2012.09.21
55
valid
t(zdout)
Delay from PCM_CLK falling to PCM_DOUT
High-Z
5
–
60 ns
Notes:
1. PCM_SYNC offset time = t(clk)/4.
3.19.3 Transmitting PCM data by USB
SIM5218E can transmit PCM data to host by USB interface.
To transmit PCM data by USB, one should make sure that driver of SIM5218E has be loaded on
host part. Then the
diagnostics
port of SIM5218E can be recognized by host. One can switch it
from
diagnostics
port mode to data mode or from data mode to
diagnostics
port mode by
AT+DSWITCH. In data mode, one can control sending and receiving PCM data by
AT+CPCMREG.
Note: Please reference document [22] for detailed information of PCM Application Note.
4 Antenna interface
The RF interface has an impedance of 50
Ω
. To suit the physical design of individual applications
SIM5218E offers two alternatives:
z
Recommended approach: antenna connector on the component side of the PCB
z
Antenna pad and grounding plane placed on the bottom side.
To minimize the loss on the RF cable, it needs to be very careful to choose RF cable. We
recommend that the insertion loss should be meet the following requirement:
z
GSM900/GSM850<1dB
z
DCS1800/PCS1900<1.5dB
z
WCDMA 2100<1.5dB
z
WCDMA 1900<1.5dB
z
WCDMA 900<1dB
z
GPS<1dB
4.1 Antenna installation
4.1.1 Antenna connector
SIM5218E use MURATA’s MM9329-2700 RF connector on the module side, we recommend that
user uses MURATA’s MXTK88XXXXX as matching connector on the application side. Please
refer to appendix for detailed infomation about MURATA’s MXTK88XXXXX.
