Service Guide
Table Of Contents
- Safety Information
- About the Document
- Contents
- Table Index
- Figure Index
- 1 Introduction
- 2 Product Overview
- 3 Operating Characteristics
- 4 Application Interfaces
- 5 Antenna Interfaces
- 6 Reliability, Radio, and Electrical Characteristics
- 7 Mechanical Information
- 8 Storage, Manufacturing, and Packaging
- 9 Appendix References
LTE Standard Module Series
EG915U_Series_Hardware_Design 51 / 90
4.7. ADC Interfaces
The module provides two analog-to-digital converter (ADC) interfaces. You can use AT+QADC=0 and
AT+QADC=1 to read the voltage values on ADC0 and ADC1 respectively. See document [2] for more
details.
To improve the accuracy of ADC, surround the trace of ADC with ground.
Table 20: Pin Definition of ADC Interfaces
Table 21: Characteristics of ADC Interfaces
then low level (0 V) for 1.2 s, before they can be configured as 1.8 V input or output. Please
evaluate whether the unstable output state on power-up meets your application design
requirements based on the specific usage scenario and circuit design.
Pin Name
Pin No.
I/O
Description
Comment
ADC0
24
AI
General-purpose ADC interfaces
A 1 kΩ series resistor is
required for use.
If unused, keep them open.
ADC1
2
AI
Parameter
Min.
Typ.
Max.
Unit
ADC0 Voltage Range
0.1
-
VBAT
V
ADC1 Voltage Range
0.1
-
VBAT
V
ADC Resolution
-
12
-
bits
1. The input voltage of ADC should not exceed its corresponding voltage range.
2. Do not supply any voltage to ADC pins when VBAT is removed.
3. Resistor divider circuit for ADC application is recommended. If the input voltage of ADC interfaces is
designed with a resistor divider circuit, the resistance value of the external divider resistor must be
less than 100 kΩ. Otherwise, the ADC measurement accuracy will be reduced significantly.
NOTE