LTE Standard Module Series
EG915U-EU_Hardware_Design 49 / 81
4.7. ADC Interface
The module provides 2 Analog-to-Digital Converter (ADC) interface. In order to improve the accuracy of
ADC, the trace of ADC interfaces should be surrounded by ground.
The module provides four analog-to-digital converter (ADC) interfaces.
AT+QADC=0
can be used to read
the voltage value on ADC0 pin.
AT+QADC=1
can be used to read the voltage value on ADC1 pin. For
more details about these AT commands, please refer to
document [2]
In order to improve the accuracy of ADC, the trace of ADC should be surrounded by ground.
Table 17: Pin Definition of ADC Interface
Table 18: Characteristics of ADC Interface
Pin Name
Pin No.
I/O
Description
Comment
ADC0
24
AI
General-purpose ADC
interface
1 k
Ω resistor must be
connected in series
when using.
ADC1
2
AI
Name
Min.
Typ.
Max.
Unit
ADC0 Voltage Range
0
-
VBAT
V
ADC1 Voltage Range
0
-
VBAT
V
ADC Resolution
-
12
-
bits
1. The input voltage of ADC should not exceed its corresponding voltage range.
2. It is prohibited to supply any voltage to ADC pin when VBAT is removed.
3. It is recommended to use resistor divider circuit for ADC application.
4. If input voltage of ADC interface is designed with a resistor divider circuit, the resistance value of the
external divider resistor must be less than 100 k
Ω
, otherwise the measurement accuracy of the
ADC will be reduced significantly.
NOTE
