Specifications

SIM7912&SIM7906 Hardware Design V1.02
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3 Interface Application
3.1 Power Supply
Module provides six VBAT pins dedicated to connection with an external power supply. There are two
separate voltage domains for VBAT.
 Four VBAT_RF pins for module’s RF part
 Two VBAT_BB pins for module’s baseband part
The following table shows details of VBAT pins and ground pins.
Table 7: VBAT pins electronic characteristics
Pin Name
Pin No.
Description
Min.
Typ.
Max.
Unit
VBAT_RF
85, 86, 87,
88
Power supply for the module’s
RF part
3.3
3.8
4.3
V
VBAT_BB
155, 156
Power supply for the module’s
baseband part
3.3
3.8
4.3
V
3.1.1 Power Supply Design Guide
The power supply range of the module is from 3.3V to 4.3V. Please make sure the input voltage will never
drop below 3.3V. The following figure shows the voltage drop during Tx power in 3G and 4G networks.
Min.
VBAT
Voltage Drop
Burst
Transmission
Ipeak
Burst
Transmission
Burst
Transmission
Figure 4: Power Supply Limits during Burst Transmission