Quectel EG915U Series Supplement

EG915U Series
Hardware Design
LTE Standard Module Series
Version: 1.0
Date: 2021-11-23
Status: Released

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Copyright © Quectel Wireless Solutions Co., Ltd. 2021. All rights reserved.

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Safety Information
The following safety precautions must be observed during all phases of operation, such as usage, service
or repair of any cellular terminal or mobile incorporating the module. Manufacturers of the cellular terminal
should notify users and operating personnel of the following safety information by incorporating these
guidelines into all manuals of the product. Otherwise, Quectel assumes no liability for customers’ failure to
comply with these precautions.
Full attention must be paid to driving at all times in order to reduce the risk of an
accident. Using a mobile while driving (even with a handsfree kit) causes
distraction and can lead to an accident. Please comply with laws and regulations
restricting the use of wireless devices while driving.
Switch off the cellular terminal or mobile before boarding an aircraft. The operation
of wireless appliances in an aircraft is forbidden to prevent interference with
communication systems. If there is an Airplane Mode, it should be enabled prior to
boarding an aircraft. Please consult the airline staff for more restrictions on the use
of wireless devices on an aircraft.
Wireless devices may cause interference on sensitive medical equipment, so
please be aware of the restrictions on the use of wireless devices when in
hospitals, clinics or other healthcare facilities.
Cellular terminals or mobiles operating over radio signal and cellular network
cannot be guaranteed to connect in certain conditions, such as when the mobile bill
is unpaid or the (U)SIM card is invalid. When emergency help is needed in such
conditions, use emergency call if the device supports it. In order to make or receive
a call, the cellular terminal or mobile must be switched on in a service area with
adequate cellular signal strength. In an emergency, the device with emergency call
function cannot be used as the only contact method considering network
connection cannot be guaranteed under all circumstances.
The cellular terminal or mobile contains a transceiver. When it is ON, it receives
and transmits radio frequency signals. RF interference can occur if it is used close
to TV sets, radios, computers or other electric equipment.
In locations with explosive or potentially explosive atmospheres, obey all posted
signs and turn off wireless devices such as mobile phone or other cellular
terminals. Areas with explosive or potentially explosive atmospheres include
fuelling areas, below decks on boats, fuel or chemical transfer or storage facilities,
and areas where the air contains chemicals or particles such as grain, dust or
metal powders.

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About the Document
Revision History
Version
Date
Author
Description
-
2021-11-23
Len CHEN/Reuben WANG/
Frank WANG/Ailsa WANG
Creation of the document
1.0
2021-11-23
Len CHEN/Reuben WANG/
Frank WANG/Ailsa WANG
First official release

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Contents
Safety Information.......................................................................................................................................3
About the Document...................................................................................................................................4
Contents.......................................................................................................................................................5
Table Index...................................................................................................................................................7
Figure Index.................................................................................................................................................8
1Introduction........................................................................................................................................10
1.1. Special Mark............................................................................................................................10
2Product Overview ..............................................................................................................................11
2.1. Frequency Bands and Functions............................................................................................ 11
2.2. Key Features...........................................................................................................................12
2.3. Functional Diagram.................................................................................................................14
2.4. Pin Assignment........................................................................................................................15
2.5. Pin Description........................................................................................................................16
2.6. EVB .........................................................................................................................................24
3Operating Characteristics.................................................................................................................25
3.1. Operating Modes.....................................................................................................................25
3.2. Sleep Mode.............................................................................................................................26
3.2.1 UARTApplication Scenario............................................................................................26
3.2.2. USB Application Scenario..............................................................................................27
3.2.2.1. USBApplication with USB Remote Wakeup Function...................................27
3.2.2.2. USB Application with USB Suspend/Resume and MAIN_RI Wakeup Function
29
3.3. Airplane Mode.........................................................................................................................30
3.3.1. Hardware........................................................................................................................30
3.3.2. Software.........................................................................................................................30
3.4. Power Supply..........................................................................................................................30
3.4.1. Power Supply Pins.........................................................................................................30
3.4.2. Reference Design for Power Supply..............................................................................31
3.4.3. Requirements for Voltage Stability.................................................................................31
3.5. Turn on....................................................................................................................................32
3.5.1. Turn on with PWPKEY...................................................................................................32
3.6. Turn off ....................................................................................................................................34
3.6.1. Turn off with PWPKEY...................................................................................................35
3.6.2. Turn off with AT Command.............................................................................................35
3.7. Reset.......................................................................................................................................36
4Application Interfaces .......................................................................................................................38
4.1. Analog Audio Interfaces..........................................................................................................38
4.1.1. Audio Interfaces Design Considerations........................................................................38
4.1.2. Microphone Interface Design.........................................................................................39

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4.1.3. Receiver Interface Design..............................................................................................39
4.2. USB Interface..........................................................................................................................40
4.3. USB_BOOT Interface..............................................................................................................42
4.4. (U)SIM Interface......................................................................................................................43
4.5. I2C and PCM Interfaces.......................................................................................................45
4.6. UART Interfaces......................................................................................................................46
4.7. ADC Interface..........................................................................................................................48
4.8. SPI Interface............................................................................................................................50
4.9. PSM Interface*........................................................................................................................50
4.10. Indication Signal......................................................................................................................51
4.10.1. Network Status Indication.......................................................................................52
4.10.2. STATUS ..................................................................................................................52
4.10.3. MAIN_RI..................................................................................................................53
4.11. Control Signal..........................................................................................................................54
5Antenna Interfaces.............................................................................................................................55
5.1. Main Antenna Interface...........................................................................................................55
5.1.1. Pin Definition..................................................................................................................55
5.1.2. Operating Frequency .....................................................................................................55
5.1.3. Reference Design of Antenna Interface.........................................................................57
5.1.4. Operating Frequency .....................................................................................................58
5.2. Antenna Installation.................................................................................................................60
5.2.1. Antenna Design Requirement........................................................................................60
5.2.2. RF Connector Recommendtion .....................................................................................60
6Electrical Characteristics & Reliability............................................................................................63
6.1. Absolute Maximum Ratings ....................................................................................................63
6.2. Power Supply Ratings.............................................................................................................63
6.3. Operation and Storage Temperatures.....................................................................................64
6.4. Power Consumption................................................................................................................64
6.5. Tx Power .................................................................................................................................72
6.6. Rx Sensitivity...........................................................................................................................73
6.7. ESD.........................................................................................................................................75
7Mechanical Information.....................................................................................................................76
7.2 Mechanical Dimensions..........................................................................................................76
7.3 Recommended Footprint.........................................................................................................78
7.3 Top and Bottom Views...................................................................................................................79
8Storage, Manufacturing & Packaging...........................................................................................80
8.1 Storage Conditions..................................................................................................................80
8.2 Manufacturing and Soldering..................................................................................................81
8.3 Packaging Specifications........................................................................................................82
Packaging Process.......................................................................................................................84
9Appendix References........................................................................................................................86

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Table Index
Table 1: Special Mark.................................................................................................................................10
Table 2: Wireless Network Type..................................................................................................................11
Table 3: I/O Parameters Definition............................................................................................................. 16
Table 4: Pin Description ............................................................................................................................. 16
Table 5: Overview of Operating Modes......................................................................................................25
Table 6: Pin Definition of Power Supply..................................................................................................... 30
Table 7: Pin Definition of PWRKEY............................................................................................................32
Table 8: Pin Description of RESET_N........................................................................................................ 36
Table 9: Pin Definition of Analog Audio Interfaces..................................................................................... 38
Table 10: Functions of the USB Interface.................................................................................................. 40
Table 11: Pin Definition of USB Interface................................................................................................... 41
Table 12: Pin Definition of USB_BOOT Interface ......................................................................................42
Table 13: Pin Definition of I2C and PCM Interfaces................................................................................ 45
Table 14: Pin Definition of Main UART Interface .......................................................................................46
Table 15: Pin Definition of Debug UART Interface.....................................................................................47
Table 16: Auxiliary UART............................................................................................................................47
Table 17: Pin Definition ofADC Interface................................................................................................... 49
Table 18: Pin Definition of PSM Interface ..................................................................................................51
Table 19: Pin Definition of Indication Signal...............................................................................................51
Table 20: Working State of Network Connection Status/Activity Indication...............................................52
Table 21: Pin Definition of STATUS............................................................................................................ 53
Table 22: Behaviors of the MAIN_RI.......................................................................................................... 54
Table 23: Pin Definition of Control Signal ..................................................................................................54
Table 24: Pin Definition of RF Antennas ....................................................................................................55
Table 25: Operating Frequency of EG915U-CN........................................................................................ 55
Table 26: Operating Frequency of EG915U-EU ........................................................................................56
Table 27: Operating Frequency of EG915U-LA.........................................................................................57
Table 28: Requirements for Antenna Design .............................................................................................60
Table 30: Operating and Storage Temperatures........................................................................................64
Table 32: EG915U-EU Current Consumption............................................................................................67
Table 33: EG915U-LACurrent Consumption............................................................................................. 70
Table 34: EG915U-CN RF Output Power.................................................................................................. 72
Table 35: EG915U-EU RF Output Power...................................................................................................72
Table 36: EG915U-LARF Output Power................................................................................................... 73
Table 37: EG915U-CN Conducted RF Receiving Sensitivity.....................................................................73
Table 40: Electrostatics Discharge Characteristics (25 °C, 45 % Relative Humidity) ...............................75
Table 41: Recommended Thermal Profile Parameters.............................................................................. 82
Table 42: Related Documents....................................................................................................................86
Table 43: Terms and Abbreviations............................................................................................................86

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Figure Index
Figure 1: Functional Diagram..................................................................................................................... 14
Figure 2: EG915U Series Module Pin Assignment (Top View)..................................................................15
Figure 3: Sleep Mode Application via UART..............................................................................................26
Figure 4: Sleep Mode Application with USB Remote Wakeup..................................................................27
Figure 5: Sleep ModeApplication with MAIN_RI.......................................................................................29
Figure 6: Reference Design of Power Supply............................................................................................31
Figure 7: Power Supply Limits during Burst Transmission........................................................................ 32
Figure 8: Power Supply..............................................................................................................................32
Figure 9: Turing on the Module Using Driving Circuit................................................................................ 33
Figure 10: Turing on the Module Using Button.......................................................................................... 33
Figure 11: Power-up Timing.......................................................................................................................34
Figure 12: Timing of Turning off Module .................................................................................................... 35
Figure 13: Reference Circuit of RESET_N by Using Driving Circuit .........................................................36
Figure 14: Reference Circuit of RESET_N by Using Button......................................................................36
Figure 15: Timing of Resetting the Module................................................................................................ 37
Figure 16: Reference Design for Microphone Interface.............................................................................39
Figure 17: Reference Design for Receiver Interface................................................................................. 40
Figure 18: Reference Circuit of USBApplication....................................................................................... 41
Figure 19: Reference Circuit of USB_BOOT Interface.............................................................................. 42
Figure 20: Reference Circuit of (U)SIM Interface with an 8-Pin (U)SIM Card Connector.........................44
Figure 21: Reference Circuit of (U)SIM Interface with a 6-Pin (U)SIM Card Connector........................... 44
Figure 22: Reference Circuit of I2 C and PCMApplication withAudio Codec ..........................................46
Figure 23: Reference Circuit with Translator Chip.....................................................................................48
Figure 24: Reference Circuit with Transistor Circuit.................................................................................. 48
Figure 25: Reference Circuit of Wake up Module from PSM..................................................................... 51
Figure 26: Reference Circuit of Network Status Indication........................................................................52
Figure 27: Reference Circuits of STATUS .................................................................................................53
Figure 28: Reference Circuit of RF Antenna.............................................................................................. 58
Figure 29: Microstrip Design on a 2-layer PCB......................................................................................... 58
Figure 30: Coplanar Waveguide Design on a 2-layer PCB.......................................................................59
Figure 31: Coplanar Waveguide Design on a 4-layer PCB (Layer 3 as Reference Ground)....................59
Figure 32: Coplanar Waveguide Design on a 4-layer PCB (Layer 4 as Reference Ground)....................59
Figure 33: Dimensions of U.FL-R-SMT Connector (Unit: mm).................................................................. 61
Figure 34: Mechanicals of U.FL-LP Connectors........................................................................................61
Figure 35: Space Factor of Mated Connector (Unit: mm).......................................................................... 62
Figure 36: Module Top and Side Dimensions (Unit: mm)..........................................................................76
Figure 37: Module Bottom Dimensions......................................................................................................77
Figure 38: Recommended Footprint (TOP View).......................................................................................78
Figure 39: Top & Bottom Views of the Module........................................................................................... 79
Figure 40: Recommended Reflow Soldering Thermal Profile ...................................................................81
Figure 41: Tape Specifications................................................................................................................... 83

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Figure 42: Reel Specifications ...................................................................................................................83
Figure 43: Tape and Reel Directions..........................................................................................................84