SIM Tech SIMCom SIM868 Series, Проектирование аппаратного обеспечения

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SIM868_Series_Hardware_Design_V1.06
45
2017-07-13
5.16. Bluetooth Antenna Interface
The Bluetooth Interface of SIM868 is compliant with Bluetooth Specification 3.0. It is recommended to reserve
the matching circuit as following:
Module
R201 BT_ANT
C201 C202
GND
(Pin21)
GND
(Pin19)
BT
Antenna
(Pin20)
Figure 39: 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 50Ω ;
The RF traces should be kept far away from the high frequency signals and strong interference source.
5.17.
Bluetooth Low Energy (BLE)
SIM868E’s Bluetooth Interface is compliant with Bluetooth v4.0 , including BT low energy (BLE).They
have the same reference circuit of Bluetooth antenna, but the BLE has lower power
consumption
Table 28:
Current consumption (CSCLK=1)
Num Test Case Current Consumption(mA) Note :CSCLK=1, VBAT=3.8V
1 Modem Stand By 0.69 Turn on flight mode with SIM Card
2
BT On with BLE advertising 2.24 Modem: off
BT: on (Interval:500ms~1250ms,
Normal=880ms)
3 BLE Connection 2.33 Modem: off
BLE: on (Connection Interval:
380ms)
4 BLE-FMP 5.44 Modem: off
BLE: on (BLE Connected, Press
Find my device)
5 BLE-PXP 5.38 Modem: off
BLE: on (BLE Connected/Out of
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