User's Manual
Table Of Contents
- About the Document
- Contents
- Table Index
- Figure Index
- 1 Introduction
- 2 Product Concept
- 3 Application Interface
- 3.1. General Description
- 3.2. Pin Assignment
- 3.3. Pin Description
- 3.4. Operating Modes
- 3.5. Power Saving
- 3.6. Power Supply
- 3.7. Turn on and off Scenarios
- 3.8. Reset the Module
- 3.9. RTC Backup
- 3.10. UART Interface
- 3.11. USIM Card Interface
- 3.12. USB Interface
- 3.13. PCM and I2C Interface
- 3.14. ADC Function
- 3.15. Network Status Indication
- 3.16. Operating Status Indication
- 3.17. Behavior of the RI
- 4 GNSS Receiver
- 5 Antenna Interface
- 6 Electrical, Reliability and Radio Characteristics
- 7 Mechanical Dimensions
- 8 Storage and Manufacturing
- 9 Appendix A Reference

UMTS/HSPA Module Series
UC20 Hardware Design
UC20_Hardware_Design Confidential / Released 50 / 84
The following figure shows the reference design of PCM interface with external codec IC.
PCM_IN
PCM_OUT
PCM_SYNC
PCM_CLK
I2C_SCL
I2C_SDA
NAU8814
Module
1.8V
4.7K
4.7K
BCLK
MCLK
FS
DACIN
ADCOUT
SCLK
SDIN
BIAS
MIC_BIAS
MIC+
MIC-
SPKOUT+
SPKOUT-
Figure 30: Reference Circuit of PCM Application with Audio Codec
1. It is recommended to reserved RC (R=22Ω, C=22pF) circuit on the PCM lines, especially for
PCM_CLK.
2. UC20 work as a master device pertaining to I2C interface.
3.14. ADC Function
The module provides two analog-to-digital converters (ADC) to digitize the analog signal to 15-bit digital
data such as battery voltage, temperature and so on. Using AT command AT+QADC=0 can read the
voltage value on ADC0 pin. Using AT command AT+QADC=1 can read the voltage value on ADC1 pin.
For more details of these AT commands, please refer to document [1].
In order to improve the accuracy of ADC, the trace of ADC should be surrounded by ground.
Table 17: Pin Definition of the ADC
Pin name
Pin NO.
Description
ADC0
45
General purpose analog to digital converter.
ADC1
44
General purpose analog to digital converter.
NOTES