SimCom SIM800C, Проектирование аппаратного обеспечения

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Smart Machine Smart Decision
SIM800C_Hardware_Design_V1.02
38
2015-4-27
Normally R101 is 0 Ω , C101 and C102 are not mounted.
4.13.2 Bluetooth Antenna Interface
It is recommended to reserve the matching circuit as following:
M odule
R 201
B T _A N T
C 201 C 202
G N D
(P in21)
G N D
(P in19)
B T
A ntenna
(P in20)
Figure 38: Bluetooth antenna matching circuit
R201, C201, C202 are the matching circuit, the value should be defined by the antenna design. Normally R201 is
0R, C202 and C201 are not mounted.
There are some suggestions for placing components and RF trace for GSM_ANT/BT_ANT:
 The RF connector is used for conducted test, so keep it as close to pin GSM_ANT as possible;
 Antenna matching circuit should be close to the antenna;
 Keep the RF traces impedance as 50 Ω ;
 The RF traces should be kept far away from the high frequency signals and strong interference
source.