Antenna Interface; Main Antenna Reference Circuit - Sunsea AIoT SIMCom SIM5800 Hardware Design

Table 20: Keypad interface
Pin Name Pin
USB_BOOT 46
GPIO69 90
GPIO65 96
Recommended keypad circuit is as the following:

4.19 Antenna Interface

SIM5800 provides three antenna interfaces including MAIN antenna, GNSS antenna, and WiFi/BT antenna. To
ensure good RF performance, users should meet the following requirements:
●
Keep the RF traces at 50Ω.
●
Maintain a complete and continuous reference ground plane from antenna pin to the RF connector.
●
The RF traces should be away from any other noisy traces.
●
Keep the RF traces as short as possible.

4.19.1 MAIN Antenna reference circuit

The recommended circuit is shown as
ANT_MAIN
Module
SIM5800_Hardware Design_V1.01
Smart Machine Smart Decision
I/O Description
I KPCOL0
O KPROW0
O KPROW1
46
KPCOL0
Module
90
KPROW0
96
KPROW1
Figure 35: Keypad reference circuit
:
Figure 36
RF connector
(optional)
86
GND
87
GND 88
Matching circuit
R1
C1 C2
42
MAIN ANT
2018-10-08