SimCom SIM7000 User Manual

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SIM7000 _Hardware Design _V1.04 2018-1-31
3.9 Other interface
3.9.1 ADC
SIM7000 has a dedicated ADC pin. It is available for digitizing analog signals such as battery
voltage and so on. Its input voltage range is from 0V to VBAT. That is the maximum measurement
range of ADC cannot exceed the input voltage of VBAT (3V~4.3V). When the voltage of the
VBAT is reduced during use, the range of ADC will also be reduced. If the input voltage of ADC
PIN exceeds its range, it is necessary to implement the resistance partial pressure on the hardware
The electronic specifications are shown in the following table.
Table 17: ADC electronic characteristics
Characteristics
Min. Typ. Max. Unit
Resolution
–
–
15
Bits
Input Range
0
VBAT
V
Input serial resistance
1
– –
MΩ
Note: “AT+CADC” can be used to read the voltage of the ADC pin, for more details, please refer
to document [1].
3.9.2 LDO
SIM7000 has a LDO power output named VDD_EXT. The output voltage is 1.8V. This voltage can
only be pulled up for the external GPIO or power supply for the level conversion circuit.
VDD_EXT
( Output)
64msVBAT
PWRKEY
( Input)
Figure 25：Power on sequence of the VDD_EXT
Table 18: Electronic characteristic
Symbol Description Min. Typ. Max. Unit
V
VDD_EXT
Output voltage 1.7 1.8 1.9 V
I
O
Output current
-
-
50
mA
Note ： The VDD_EXT is used to the IO power in the module. The Output voltage is not
supported to adjust.
SIMCOM CONFIDENTIAL FILE

SimCom SIM7000 Specifications

General

Brand	SimCom
Model	SIM7000
Category	GSM/GPRS Modules
Language	English