Quectel EG915U-EU User manual

EG915U-EU
Hardware Design
LTE Standard Module Series
Version: 1.0.0
Date: 2021-06-24
Status: Preliminary

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Our aim is to provide customers with timely and comprehensive service. For any assistance,
please contact our company headquarters:
Quectel Wireless Solutions Co., Ltd.
Building 5, Shanghai Business Park Phase III (Area B), No.1016 Tianlin Road, Minhang District, Shanghai
200233, China
Tel: [phone]
Email: [email protected]om
Or our local office. For more information, please visit:
http://www.quectel.com/support/sales.htm.
For technical support, or to report documentation errors, please visit:
http://www.quectel.com/support/technical.htm
Or email to [e-mail].
General Notes
Quectel offers the information as a service to its customers. The information provided is based upon
customers’ requirements. Quectel makes every effort to ensure the quality of the information it makes
available. Quectel does not make any warranty as to the information contained herein, and does not
accept any liability for any injury, loss or damage of any kind incurred by use of or reliance upon the
information.All information supplied herein is subject to change without prior notice.
Disclaimer
While Quectel has made efforts to ensure that the functions and features under development are free
from errors, it is possible that these functions and features could contain errors, inaccuracies and
omissions. Unless otherwise provided by valid agreement, Quectel makes no warranties of any kind,
implied or express, with respect to the use of features and functions under development. To the maximum
extent permitted by law, Quectel excludes all liability for any loss or damage suffered in connection with
the use of the functions and features under development, regardless of whether such loss or damage
may have been foreseeable.
Duty of Confidentiality
The Receiving Party shall keep confidential all documentation and information provided by Quectel,
except when the specific permission has been granted by Quectel. The Receiving Party shall not access
or use Quectel’s documentation and information for any purpose except as expressly provided herein.
Furthermore, the Receiving Party shall not disclose any of the Quectel's documentation and information
to any third party without the prior written consent by Quectel. For any noncompliance to the above
requirements, unauthorized use, or other illegal or malicious use of the documentation and information,
Quectel will reserve the right to take legal action.

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Copyright
The information contained here is proprietary technical information of Quectel Wireless Solutions Co., Ltd.
Transmitting, reproducing, disseminating and editing this document as well as using the content without
permission are forbidden. Offenders will be held liable for payment of damages. All rights are reserved in
the event of a patent grant or registration of a utility model or design.
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 emergent 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
fueling 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
-
2021-06-24
Kexiang ZHANG/Len CHEN
Creation of the document
1.0.0
2021-06-24
Kexiang ZHANG/Len CHEN
Preliminary

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Contents
Safety Information.......................................................................................................................................3
About the Document...................................................................................................................................4
Table Index...................................................................................................................................................7
Figure Index.................................................................................................................................................8
1Introduction........................................................................................................................................10
1.1. Special Mark............................................................................................................................10
2Product Overview ..............................................................................................................................11
2.1. Frequency Bands and Functions............................................................................................12
2.2. Key Features...........................................................................................................................13
2.3. Functional Diagram.................................................................................................................15
2.4. Pin Assignment........................................................................................................................15
2.5. Pin Description........................................................................................................................17
2.6. EVB .........................................................................................................................................25
3Operating Characteristics.................................................................................................................26
3.1. Operating Modes.....................................................................................................................26
3.2. Sleep Mode.............................................................................................................................27
3.2.1. UARTApplication Scenario............................................................................................27
3.2.2. USB Application Scenario..............................................................................................27
3.2.2.1. USB Application with USB Remote Wakeup Function* ................................. 28
3.2.2.2. USBApplication with USB Suspend/Resume and RI Function.....................29
3.3. Airplane Mode.........................................................................................................................29
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 ...................................................................................................................................33
3.5.1. Turn on the Module with PWRKEY................................................................................33
3.6. Turn Off....................................................................................................................................34
3.6.1. Turn off the Module with PWRKEY................................................................................35
3.6.2. Turn off the Module with AT Command..........................................................................35
3.7. Reset.......................................................................................................................................36
4Application Interfaces .......................................................................................................................38
4.1. Analog Audio Interfaces..........................................................................................................38
4.1.1. Audio Interfaces Design.................................................................................................38
4.1.2. Microphone Interface Design.........................................................................................39
4.1.3. Receiver Interface Design..............................................................................................40
4.2. USB Interface..........................................................................................................................40
4.3. USB_BOOT Interface..............................................................................................................42
4.4. (U)SIM Interface......................................................................................................................43
4.5. I2C and PCM Interfaces..........................................................................................................45

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4.6. UART Interface........................................................................................................................46
4.7. ADC Interface..........................................................................................................................49
4.8. SPI Interface............................................................................................................................50
4.9. Control Signal..........................................................................................................................50
4.9.1. W_DISABLE#.................................................................................................................51
4.10. Indication Signal......................................................................................................................51
4.10.1. Network Status Indication.......................................................................................51
4.10.2. STATUS ..................................................................................................................52
4.10.3. MAIN_RI..................................................................................................................53
5RF Specifications...............................................................................................................................54
5.1. Cellular Network......................................................................................................................54
5.1.1. Antenna Interface & Frequency Bands..........................................................................54
5.1.2. Tx Power........................................................................................................................55
5.1.3. Receiving Sensitivity......................................................................................................55
5.1.4. Reference Design ..........................................................................................................56
5.1.5. GRFC Interfaces*...........................................................................................................57
5.2. Reference Design of RF Routing............................................................................................58
5.3. Requirements for Antenna Design..........................................................................................60
5.4. RF Connector Recommendation ............................................................................................60
6Electrical Characteristics & Reliability............................................................................................62
6.1. Absolute Maximum Ratings ....................................................................................................62
6.2. Power Supply Ratings.............................................................................................................63
6.3. Power Consumption................................................................................................................63
6.4. ESD.........................................................................................................................................64
6.5. Operating and Storage Temperatures.....................................................................................65
7Mechanical Information.....................................................................................................................66
7.1. Mechanical Dimensions..........................................................................................................66
7.2. Recommended Footprint.........................................................................................................68
7.3. Top and Bottom Views.............................................................................................................69
8Storage, Manufacturing & Packaging...........................................................................................70
8.1. Storage Conditions..................................................................................................................70
8.2. Manufacturing and Soldering..................................................................................................72
8.3. Packaging Specifications........................................................................................................73
9Appendix References........................................................................................................................76

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Table Index
Table 1: Special Mark.................................................................................................................................10
Table 2: Brief Introduction of the Module....................................................................................................11
Table 3: Wireless Network Type.................................................................................................................12
Table 4: Key Features................................................................................................................................13
Table 5: I/O Parameters Definition.............................................................................................................17
Table 6: Pin Description .............................................................................................................................17
Table 7: Overview of Operating Modes...................................................................................................... 26
Table 8: Pin Definition of Power Supply.....................................................................................................30
Table 9: Pin Definition of PWRKEY............................................................................................................ 33
Table 10: Pin Definition of RESET.............................................................................................................36
Table 11: Pin Definition ofAudio Interfaces................................................................................................38
Table 12: Functions of the USB Interface..................................................................................................40
Table 13: Pin Definition of USB Interface................................................................................................... 41
Table 14: Pin Definition of (U)SIM Interface............................................................................................... 43
Table 15: Pin Definition of I2C Interface.....................................................................................................45
Table 16: Pin Definition of UART Interface ................................................................................................46
Table 17: Pin Definition ofADC Interface...................................................................................................49
Table 18: Characteristics of ADC Interface................................................................................................ 49
Table 19: Pin Definition of SPI Interface.................................................................................................... 50
Table 20: Pin Definition of Control Signal ..................................................................................................50
Table 21: Pin Definition of Indication Signal............................................................................................... 51
Table 22: Working State of the Network Connection Status/Activity Indication.........................................51
Table 23: Behaviors of the MAIN_RI.......................................................................................................... 53
Table 24: Pin Definition of Cellular Network Interface ...............................................................................54
Table 25: Operating Frequency of EG915U-EU ........................................................................................ 54
Table 26: Tx Power.....................................................................................................................................55
Table 27: Conducted RF Receiving Sensitivity of EG915U-EU.................................................................55
Table 28: Pin Definition of GRFC Interfaces.............................................................................................. 57
Table 29: Logic Levels of GRFC Interfaces............................................................................................... 57
Table 30: Truth Table of GRFC Interfaces..................................................................................................57
Table 31: Requirements for Antenna Design .............................................................................................60
Table 32: Absolute Maximum Ratings........................................................................................................ 62
Table 33: The Module’s Power Supply Ratings .........................................................................................63
Table 34: The Module Power Consumption............................................................................................... 63
Table 35: The Module GNSS Current Consumption.................................................................................. 64
Table 36: Electrostatics Discharge Characteristics (25 °C, 45 % Relative Humidity) ...............................64
Table 37: Operating and Storage Temperatures........................................................................................65
Table 38: Recommended Thermal Profile Parameters.............................................................................. 72
Table 39: Related Documents.................................................................................................................... 76
Table 40: Terms and Abbreviations............................................................................................................ 76

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Figure Index
Figure 1: EG915U-EU Functional Diagram ...............................................................................................15
Figure 2: EG915U-EU PinAssignment (Top View).................................................................................... 16
Figure 3: Sleep Mode Application via UART.............................................................................................. 27
Figure 4: Sleep Mode Application with USB Remote Wakeup.................................................................. 28
Figure 5: Sleep Mode Application with RI..................................................................................................29
Figure 6: Reference Design of Power Supply............................................................................................31
Figure 7: Power Supply Limits during Burst Transmission........................................................................ 31
Figure 8: Star Structure of the Power Supply............................................................................................ 32
Figure 9: Reference Circuit of Turing on the Module with Driving Circuit.................................................. 33
Figure 10: Reference Circuit of Turing on the Module with Keystroke...................................................... 33
Figure 11: Power-on Timing....................................................................................................................... 34
Figure 12: Power-down Timing ..................................................................................................................35
Figure 13: Reference Circuit of RESET_N with Driving Circuit.................................................................36
Figure 14: Reference Circuit of RESET_N with Button............................................................................. 36
Figure 15: Reset Timing.............................................................................................................................37
Figure 16: Reference Design for Microphone Interface.............................................................................39
Figure 17: Reference Design for Receiver Interface.................................................................................40
Figure 18: Reference Circuit of USB Application....................................................................................... 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 a 6-Pin (U)SIM Card Connector.............................................................. 44
Figure 22: Reference Circuit of PCMApplication with Audio Codec.........................................................46
Figure 23: Reference Circuit with Translator Chip..................................................................................... 47
Figure 24: Reference Circuit with Transistor Circuit.................................................................................. 48
Figure 25: Reference Circuit of the Network Status Indication..................................................................52
Figure 26: Reference Circuits of STATUS .................................................................................................52
Figure 27: Reference Circuit for RF Antenna Interfaces............................................................................ 56
Figure 28: Microstrip Design on a 2-layer PCB......................................................................................... 58
Figure 29: Coplanar Waveguide Design on a 2-layer PCB....................................................................... 58
Figure 30: Coplanar Waveguide Design on a 4-layer PCB (Layer 3 as Reference Ground).................... 59
Figure 31: Coplanar Waveguide Design on a 4-layer PCB (Layer 4 as Reference Ground).................... 59
Figure 32: Dimensions of U.FL-R-SMT Connector (Unit: mm).................................................................. 60
Figure 33: Mechanicals of U.FL-LP Connectors........................................................................................ 61
Figure 34: Space Factor of Mated Connector (Unit: mm)..........................................................................61
Figure 35: Module Top and Side Dimensions (Unit: mm)..........................................................................66
Figure 36: Module Bottom Dimensions...................................................................................................... 67
Figure 37: Recommended Footprint (TOP View).......................................................................................68
Figure 38: Top & Bottom Views of the Module...........................................................................................69
Figure 39: Recommended Reflow Soldering Thermal Profile ...................................................................72
Figure 40: Tape Specifications...................................................................................................................74
Figure 41: Reel Specifications ...................................................................................................................74

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Figure 42: Tape and Reel Directions..........................................................................................................75

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1Introduction
This document defines the EG915U-EU module and describes its air interfaces and hardware interfaces
which relate to customers’ applications.
It can help customers quickly understand interface specifications, electrical and mechanical details, as
well as other related information of the module. Associated with application notes and user guides,
customers can use this module to design and to set up mobile applications easily.
1.1. Special Mark
Table 1: Special Mark
Mark
Definition
*
Unless otherwise specified, when an asterisk (*) is used after a function, feature, interface,
pin name, AT command, or argument, it indicates that the function, feature, interface, pin,
AT command, or argument is under development and currently not supported; and the
asterisk (*) after a model indicates that the sample of such model is currently unavailable.

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2Product Overview
The module is an LTE module, supports LTE-FDD, LTE-TDD and GSM network data connection. It
also provides voice functionality, Bluetooth and Wi-Fi Scan for customer’s specific applications.
Related information and details are listed in the table below:
Table 2: Brief Introduction of the Module
Categories
Packaging and pins number
LGA; 126
Dimensions
23.6 mm ×19.9 mm ×2.4 mm
Weight
TBD
Wireless network functions
LTE/GSM/Bluetooth/Wi-Fi Scan
1. The Bluetooth and Wi-Fi Scan functions of the EG915U-EU are integrated, but the Bluetooth and
Wi-Fi Scan functions cannot be used at the same time, and only one of them can be selected.
2. EG915U-EU supports Bluetooth and Wi-Fi functions. Because of common antenna interfaces, two
functions cannot be used at the same time: Bluetooth and Wi-Fi are optional (both supported or
not). It also provides models that do not support Bluetooth and Wi-Fi Scan functions. Please consult
Quectel Technical Support for details.
NOTE

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2.1. Frequency Bands and Functions
Table 3: Wireless Network Type
1
Optional.
Wireless Network Type
EG915U-EU
LTE-FDD
B1/B3/B5/B7/B8/B20/B28
GSM
850/900/1800/1900 MHz
Bluetooth/Wi-Fi Scan 1
2.4 GHz

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2.2. Key Features
Table 4: Key Features
Features
Details
Power Supply
⚫Supply voltage: 3.3 V-4.3 V
⚫Typical supply voltage: 3.8 V
SMS
⚫Text and PDU mode.
⚫Point-to-point MO and MT.
⚫SMS cell broadcast.
⚫SMS storage: ME by default.
(U)SIM Interface
Supports USIM/SIM card: 1.8 V, 3.0 V
Audio Features
⚫Supports two analog audio interfaces: one analog
audios input and one analog audios output.
⚫GSM: HR/FR/EFR/AMR/AMR-WB
PCM Interface
⚫Used for audio function with external codec
⚫Supports slave modes, not master mode.
SPI Interface
⚫Provides a duplex, synchronous and serial
communication link with the peripheral devices.
⚫One SPI interface, only supports master mode.
⚫1.8 V operation voltage with clock rates up to 25 MHz.
I2C Interface
⚫One I2C interface
⚫Comply with I2C-bus specification version
USB Interface
⚫Compliant with USB 2.0 specification (only slave),
with transmission rates up to 480 Mbps
⚫Used for AT command communication, data
transmission, software debugging, firmware upgrade
USB Serial Driver: supports USB serial driver for
Windows 7/8/8.1/10, Linux 2.6/3.x/4.1–5.12 and
Android 4.x–11.x systems
UART Interfaces
Main UART:
⚫Used for AT command communication and data
transmission.
⚫Baud rate: 115200 bps by default.
⚫Supports RTS and CTS hardware flow control.
Debug UART:
⚫Used for Linux console and log output.
⚫Baud rate: 921600 bps.
⚫Only use for debug UART, cannot use for universal
UART.

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2
Within operating temperature range, the module is 3GPP compliant.
3
Within extended operating temperature range, proper mounting, heating sinks and active cooling may
be required to make certain functions of the module such as voice, SMS, data transmission to be realized.
Only one or more parameters like Pout might reduce in their value and exceed the specified tolerances.
When the temperature returns to normal operating temperature levels, the module will meet 3GPP
specifications again.
Auxiliary UART
Network Indication
NET_STATUS to indicate network connectivity status.
AT Commands
Compliant with 3GPP TS 27.007, 27.005 and Quectel
enhanced AT commands.
Antenna Interface
⚫ANT_MAIN
⚫Bluetooth and Wi-Fi Scan antenna interface
(ANT_BT/WIFI_SCAN)
⚫50 Ω impedance.
Transmitting Power
⚫GSM850/EGSM900：Class 4 (33 dBm ±2 dB)
⚫DCS1800/PCS1900：Class 1 (30 dBm ±2 dB)
⚫LTE-FDD：Class 3 (23 dBm ±2 dB)
⚫DCS1800: Class 1 (30 dBm ±2 dB)
LTE Features
⚫Supports up to non-CACat 1 FDD
⚫Supports 1.4/3/5/10/15/20 MHz RF bandwidth
⚫Supports uplink QPSK, 16-QAM
⚫Supports downlink QPSK, 16-QAM and 64-QAM
⚫FDD: Max 10 Mbps (DL) / 5 Mbps (UL)
GSM Features
GPRS:
⚫Supports GPRS multi-slot class 12
⚫Coding scheme: CS 1-4
Max 85.6 Kbps (DL)/ 85.6 Kbps (UL)
Internet Protocol Features
⚫Supports TCP/UDP/PPP/NTP/NITZ/FTP/HTTP/PING
/CMUX/HTTPS/FTPS/SSL/FILE/MQTT/MMS protoco
ls.
⚫Supports the protocols PAP (Password Authentication
Protocol) and CHAP (Challenge Handshake
Authentication Protocol).
Firmware Upgrade
Use USB interface or FOTA to upgrade.
Temperature Range
⚫Operating temperature range: -35 °C to +75 °C 2
⚫Extended operating temperature range: -40 °C to
+85 °C 3
⚫Storage temperature range: -40 °C to +95 °C
RoHS
All hardware components are fully compliant with EU
RoHS directive.

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2.3. Functional Diagram
The following figure shows a block diagram of the module and illustrates the major functional parts.
⚫Power management
⚫Baseband
⚫Radio frequency
⚫Peripheral interface
Baseband
PMIC
Transceiver
PA
PAM
ANT_MAIN
VBAT_RF
PWRKEY
ADCs
VDD_EXT 2x(U)SIM PCM UARTsI2C
Control
Duplex
Tx
PRx
STATUS
RESET_N
SAW
ANT_BT/WIFI_SCAN
26 MHz
DCXO
SPI Nor Flash (64Mb)
PSRAM (128Mb)
MIC
32 kHz Clock
USB SPI
SPK
Control
VBAT_BB
Figure 1: EG915U-EU Functional Diagram
2.4. Pin Assignment

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The following figure illustrates the pin assignment of the module.
1
2
3
4
5
6
7
11
12
13
14
15
16
17
18
50 51 52 53 54
55
58 59 60 61 62
31 30 29 28 27 26 23 22
21 20 19
10
9
8
49
48
47
46
45
44
43
40
41
42
39
38
37
36
35
34
33
32
24 25
57
56
63
64
65
66
67
68
83
84
85
86
87
88
98
97
96
95
94
93
78
77
76
75
74
73
91 92
89 90
71 72
69 70
80 79
82 81
100 99
102 101
PSM_IND
ADC1
RESERVED
SPI_CS SPI_CLK
ANT_MAIN
AP_READY
STATUS
NET_STATUS
PCM_CLK
PCM_SYNC
PCM_DIN
PCM_DOUT
W_DISABLE#
GND
USB_VBUS
USB_DP
USB_DM
RESERVED
RESERVED
RESERVED
RESERVED
PWRKEY
DBG_RXD
DBG_TXD
ADC0
VDD_EXT
MAIN_DTR
GND
MAIN_RI
MAIN_DCD
MAIN_RTS
MAIN_TXD
MAIN_RXD
VBAT_BB
MAIN_CTS
I2C_SCL
I2C_SDA
VBAT_BB
GND
GND
GND
RESERVED
VBAT_RF VBAT_RF
GND GND
AN T_BT/WIFI_ SC AN
GND GND
AUX_TXD
AUX_RXD
RESET_N
USB_BOOT
USIM2_DET
USIM2_CLK
USIM2_RST
US IM2_DA TA
USIM2_VDD
SPI_DIN
SPI_DOUT
RESERVED
RESERVED
PSM_EINT
I2S_CLK
RESERVED
GRFC1
GRFC2
103
104
103
115
114 103
118
113
2
112
111
103
106
105
107
116 103
108
117
109
110
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
RESERVED RESERVED RESERVED
RESERVED RESERVED
RESERVEDRESERVED
RESERVED RESERVED
RESERVED
RESERVED
RESERVED
RESERVED
119 126
120
121
122 123
124
125
MIC_N MIC_P
SPK_P
SPK_N RESERVED
RESERVED
RESERVED
MICBIAS
Power Pins
GND Pins Signal Pins
RESERVED Pins (U)SIM Pins
USB Pins
ADC Pins UART2 Pins UART1 Pins
Debug UART Pins
SPI Pins Audio Pins
PCM Pins
USIM1_CLK
USIM1_DATA
USIM1_RST
USIM1_VDD
USIM1_GND
USIM1_DET
RESERVED
GND
PSM Pins IIC Pins
RESERVED
Figure 2: EG915U-EU Pin Assignment (Top View)
1. USB_BOOT cannot be pulled up before the module startup.
2. Keep NC and RESERVED pins unconnected, all GND pins shall be connected to the ground.
3. The functions of pin 1 and pin 63 are under development and we do not recommend using them.
4. USIM2 is under development, not recommended for the time being. For details, please contact the
technical support of remote communication.
NOTE

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2.5. Pin Description
The following table shows the DC characteristics and pin descriptions.
Table 5: I/O Parameters Definition
Table 6: Pin Description
Type
Description
AI
Analog Input
AIO
Analog Input/Output
DI
Digital Input
DO
Digital Output
DIO
Digital Input/Output
OD
Open Drain
PI
Power Input
PO
Power Output
Power Supply
Pin Name
Pin No.
I/O
Description
DC
Characteristics
Comment
VBAT_BB
32, 33
PI
Power supply for the
module’s baseband part
Vmax = 4.3 V
Vmin = 3.3 V
Vnom = 3.8 V
It must be
provided with
sufficient current
up to 1 A
VBAT_RF
52, 53
PI
Power supply for the
module’s RF part
It must be
provided with
sufficient current
up to 2.5 A
VDD_EXT
29
PO
Provide 1.8 V for
external circuit
Vnom = 1.8 V
IOmax = 50 mA
Power supply for
external GPIO’s
pull-up circuits.
Add 2.2 μF
bypass capacitor

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when in use.
If unused, keep it
open.
Turn On/Off
Pin Name
Pin No.
I/O
Description
DC
Characteristics
Comment
PWRKEY
15
DI
Turn on/off the module
VILmax = 0.5 V
VBAT power
domain.
RESET_N
17
DI
Reset the module
VBAT power
domain.
If unused, keep it
open.
PSM_EINT*
96
DI
External interrupt pin;
Wake up the module
from PSM
If unused, keep it
open.
Indication Interface
Pin Name
Pin No.
I/O
Description
DC
Characteristics
Comment
STATUS
20
DO
Indicate the module's
operation status
VOHmin = 1.35 V
VOLmax = 0.45 V
1.8 V power
domain.
If unused, keep
it open
NET_STATUS
21
DO
Indicate the module's
network activity status
VOHmin = 1.35 V
VOLmax = 0.45 V
1.8 V power
domain.
If unused, keep it
open.
PSM_IND*
1
DO
Indicate the module’s
power saving mode
USB Interface
Pin Name
Pin No.
I/O
Description
DC
Characteristics
Comment
USB_VBUS
8
AI
USB connection detect
Vmax = 5.25 V
Vmin = 3.5 V
Vnom = 5.0 V
Typical: 5.0 V
If unused, keep it
open.
USB_DP
9
AIO
USB differential data (+)
USB 2.0
compliant.
Require
differential
impedance of 90
Ω.
If unused, keep it
open.
USB_DM
10
AIO
USB differential data (-)

LTE Standard Module Series
EG915U-EU_Hardware_Design 19 / 81
(U)SIM Interface
Pin Name
Pin No.
I/O
Description
DC
Characteristics
Comment
USIM1_VDD
43
PO
(U)SIM1 card power
supply
IOmax = 50 mA
For 1.8 V
(U)SIM:
Vmax = 1.9 V
Vmin = 1.7 V
For 3.0 V
(U)SIM:
Vmax = 3.05 V
Vmin = 2.7 V
Either 1.8 V or
3.0 V (U)SIM
card is
supported and
can be identified
automatically by
the module.
USIM1_DATA
45
DIO
(U)SIM1 card data
For 1.8 V
(U)SIM:
VILmax = 0.6 V
VIHmin = 1.26 V
VOLmax = 0.45 V
VOHmin = 1.35 V
For 3.0 V
(U)SIM:
VILmax = 1.0 V
VIHmin = 1.95 V
VOLmax = 0.45 V
VOHmin = 2.55 V
USIM1_CLK
46
DO
(U)SIM1 card clock
For 1.8 V
(U)SIM:
VOLmax = 0.45 V
VOHmin = 1.35 V
For 3.0 V
(U)SIM:
VOLmax = 0.45 V
VOHmin = 2.55 V
USIM1_RST
44
DO
(U)SIM1 card reset
For 1.8 V
(U)SIM:
VOLmax = 0.45 V
VOHmin = 1.35 V
For 3.0 V
(U)SIM: