SIM Tech SIMCom SIM800 - RF Synchronization Signal; Antenna Interface

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SIM800_Hardware Design_V1.09 48 2016-06-30
Module
VBAT
KPLED
Figure 44: KPLED driver reference circuit
Table 32: KPLED specification
4.19. RF Synchronization Signal
The synchronization signal serves to indicate growing power consumption during the transmit burst.
Table 33: Definition of the RF_SYNC pin
Note: Do not pull up RF_SYNC.
The timing of the synchronization signal is shown in the following figure. High level of the RF_SYNC signal
indicates increased power consumption during transmission.
Transmit burst
RF_SYNC
577us
220us
Figure 45: RF_SYNC signal during transmit burst
4.20. Antenna Interface
There are two antenna ports for SIM800, GSM antenna port named GSM_ANT and Bluetooth antenna port
Pin name
Min
Typ
Max
Unit
KPLED
-
60
mA
Pin name
Pin number
Description
RF_SYNC
67
Transmit synchronization signal