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 48 / 90
PCM_DIN
PCM_DOUT
PCM_SYNC
PCM_CLK
I2C_SCL
I2C_SDA
Module
4.7K
4.7K
BCLK
LRCK
DAC
ADC
SCL
SDA
BIAS
MICBIAS
INP
INN
LOUTP
LOUTN
Codec
1.8 V
External 26MHz Crystal
0R
NM 0R
CAM_MCLK
MCLK
Figure 23: Reference Circuit of I2C and PCM Application with Audio Codec
1. It is recommended to reserve an RC (R = 22 Ω, C = 22 pF) circuit on the PCM traces, especially for
PCM_CLK.
2. The I2C interface supports simultaneous connection of multiple peripherals except for codec IC. In
other words, if a codec IC has been mounted on the I2C bus, no other peripherals can be mounted; if
there is no codec IC on the bus, multiple peripherals can be mounted.
4.6. UART Interfaces
The module provides three UART interfaces: main UART, debug UART, and auxiliary UART. Their
features are described as follows.
⚫ Main UART interface supports baud rates of 4800 bps, 9600 bps, 19200 bps, 38400 bps, 57600 bps,
115200 bps, 230400 bps, 460800 bps, and 921600 bps, and the default setting is 115200 bps. It
supports RTS and CTS hardware flow control. This interface is used for data transmission and AT
command communication.
⚫ Debug UART interface supports 921600 bps baud rate. It is used for log output.
⚫ Auxiliary UART.
NOTE