Quectel BG77 Supplement

BG77 Hardware Design
LPWA Module Series
Rev. BG77_Hardware_Design_V1.1
Date: 2019-10-08
Status: Preliminary
www.quectel.com

LPWA Module Series
BG77 Hardware Design
BG77_Hardware_Design 1/76
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,
China 200233
Tel: [phone]
Email: [email protected]
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: [email protected]
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.
COPYRIGHT
THE INFORMATION CONTAINED HERE IS PROPRIETARY TECHNICAL INFORMATION OF
QUECTEL WIRELESS SOLUTIONS CO., LTD. TRANSMITTING, REPRODUCTION, DISSEMINATION
AND EDITING OF THIS DOCUMENT AS WELL AS UTILIZATION OF THE CONTENT ARE
FORBIDDEN WITHOUT PERMISSION. 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. 2019. All rights reserved.

LPWA Module Series
BG77 Hardware Design
BG77_Hardware_Design 2/76
About the Document
History
Revision Date Author Description
1.0 2019-06-17
Jake JIANG/
Newgate HUA Initial
1.1 2019-10-08
Lyndon LIU/
Watt ZHU
1. Delete GNSS optional information.
2. Updated the power supply in Table 3.
3. Updated Pin Assignment in Figure 2.
4. Updated Pin Description in Table 3.
5. Added PON_TRIG pin to wake-up the module from
PSM in Chapter 3.4.2.
6. Updated the power supply in Chapter 3.5.
7. Added automatically turn-on circuit in chapter 3.61.
8. Added PON_TRIG information in chapter 3.8.
9. Added GRFC interfaces description in chapter 3.20.
10. Updated the absolute maximum ratings in Chapter 6.1.
11. Updated the power supply ratings in Chapter 6.3.

LPWA Module Series
BG77 Hardware Design
BG77_Hardware_Design 3/76
Contents
About the Document................................................................................................................................ 2
Contents.................................................................................................................................................... 3
Table Index ............................................................................................................................................... 5
Figure Index.............................................................................................................................................. 7
1 Introduction....................................................................................................................................... 9
1.1. Safety Information .................................................................................................................. 10
2 Product Concept ............................................................................................................................. 11
2.1. General Description................................................................................................................ 11
2.2. Key Features .......................................................................................................................... 12
2.3. Functional Diagram ................................................................................................................ 13
2.4. Evaluation Board .................................................................................................................... 14
3 Application Interfaces..................................................................................................................... 15
3.1. Pin Assignment ...................................................................................................................... 16
3.2. Pin Description ....................................................................................................................... 17
3.3. Operating Modes.................................................................................................................... 24
3.4. Power Saving ......................................................................................................................... 25
3.4.1. Airplane Mode.............................................................................................................. 25
3.4.2. Power Saving Mode (PSM).......................................................................................... 26
3.4.3. Extended Idle Mode DRX (e-I-DRX) ............................................................................ 27
3.4.4. Sleep Mode.................................................................................................................. 27
3.4.4.1. UART Application .............................................................................................. 27
3.5. Power Supply ......................................................................................................................... 28
3.5.1. Power Supply Pins....................................................................................................... 28
3.5.2. Decrease Voltage Drop ............................................................................................... 29
3.5.3. Monitor the Power Supply............................................................................................ 29
3.6. Power on and off Scenarios ................................................................................................... 30
3.6.1. Turn on Module Using the PWRKEY Pin..................................................................... 30
3.6.2. Turn off Module............................................................................................................ 32
3.6.2.1. Turn off Module Using the PWRKEY Pin........................................................... 32
3.6.2.2. Turn off Module Using AT Command ................................................................ 32
3.7. Reset the Module* .................................................................................................................. 32
3.8. PON_TRIG Interface .............................................................................................................. 34
3.9. (U)SIM Interface ..................................................................................................................... 35
3.10. USB Interface ......................................................................................................................... 37
3.11. UART Interfaces..................................................................................................................... 39
3.12. PCM and I2C Interfaces*........................................................................................................ 42
3.13. Network Status Indication....................................................................................................... 43
3.14. STATUS ................................................................................................................................. 44

LPWA Module Series
BG77 Hardware Design
BG77_Hardware_Design 4/76
3.15. Behaviors of RI* ..................................................................................................................... 45
3.16. USB_BOOT Interface ............................................................................................................. 45
3.17. ADC Interfaces ....................................................................................................................... 46
3.18. SPI Interface* ......................................................................................................................... 47
3.19. GPIO Interfaces* .................................................................................................................... 48
3.20. GRFC Interfaces* ................................................................................................................... 49
4 GNSS Receiver................................................................................................................................ 50
4.1. General Description................................................................................................................ 50
4.2. GNSS Performance................................................................................................................ 50
4.3. Layout Guidelines................................................................................................................... 51
5 Antenna Interfaces.......................................................................................................................... 52
5.1. Main Antenna Interface .......................................................................................................... 52
5.1.1. Pin Definition................................................................................................................ 52
5.1.2. Operating Frequency ................................................................................................... 52
5.1.3. Reference Design of RF Antenna Interface ................................................................. 53
5.1.4. Reference Design of RF Layout................................................................................... 54
5.2. GNSS Antenna Interface ........................................................................................................ 56
5.3. Antenna Installation................................................................................................................ 57
5.3.1. Antenna Requirements ................................................................................................ 57
5.3.2. Recommended RF Connector for Antenna Installation................................................ 58
6 Electrical, Reliability and Radio Characteristics.......................................................................... 60
6.1. Absolute Maximum Ratings.................................................................................................... 60
6.2. Power Supply Ratings ............................................................................................................ 60
6.3. Operation and Storage Temperatures .................................................................................... 61
6.4. Current Consumption ............................................................................................................. 61
6.5. RF Output Power.................................................................................................................... 63
6.6. RF Receiving Sensitivity......................................................................................................... 64
6.7. Electrostatic Discharge........................................................................................................... 65
7 Mechanical Dimensions.................................................................................................................. 66
7.1. Mechanical Dimensions of the Module ................................................................................... 66
7.2. Recommended Footprint ........................................................................................................ 68
7.3. Design Effect Drawings of the Module.................................................................................... 69
8 Storage, Manufacturing and Packaging........................................................................................ 70
8.1. Storage................................................................................................................................... 70
8.2. Manufacturing and Soldering.................................................................................................. 71
8.3. Packaging............................................................................................................................... 72
9 Appendix A References.................................................................................................................. 74

LPWA Module Series
BG77 Hardware Design
BG77_Hardware_Design 5/76
Table Index
TABLE 1: FREQUENCY BANDS AND GNSS TYPES OF BG77 MODULE..................................................... 11
TABLE 2: KEY FEATURES OF BG77 MODULE .............................................................................................. 12
TABLE 3: DEFINITION OF I/O PARAMETERS ................................................................................................ 17
TABLE 4: PIN DESCRIPTION........................................................................................................................... 17
TABLE 5: OVERVIEW OF OPERATING MODES ............................................................................................ 25
TABLE 6: VBAT AND GND PINS...................................................................................................................... 28
TABLE 7: PIN DEFINITION OF PWRKEY ........................................................................................................ 30
TABLE 8: PIN DEFINITION OF RESET_N ....................................................................................................... 33
TABLE 9: PIN DEFINITION OF PON_TRIG INTERFACE................................................................................ 34
TABLE 10: PIN DEFINITION OF (U)SIM INTERFACE..................................................................................... 35
TABLE 11: PIN DEFINITION OF USB INTERFACE......................................................................................... 37
TABLE 12: PIN DEFINITION OF MAIN UART INTERFACE ............................................................................ 40
TABLE 13: PIN DEFINITION OF DEBUG UART INTERFACE......................................................................... 40
TABLE 14: PIN DEFINITION OF GNSS UART INTERFACE ........................................................................... 40
TABLE 15: LOGIC LEVELS OF DIGITAL I/O ................................................................................................... 41
TABLE 16: PIN DEFINITION OF PCM AND I2C INTERFACES ...................................................................... 42
TABLE 17: PIN DEFINITION OF NETLIGHT.................................................................................................... 43
TABLE 18: WORKING STATE OF NETLIGHT ................................................................................................. 43
TABLE 19: PIN DEFINITION OF STATUS ....................................................................................................... 44
TABLE 20: DEFAULT BEHAVIORS OF RI ....................................................................................................... 45
TABLE 21: PIN DEFINITION OF USB_BOOT INTERFACE............................................................................. 46
TABLE 22: PIN DEFINITION OF ADC INTERFACES ...................................................................................... 47
TABLE 23: CHARACTERISTICS OF ADC INTERFACES................................................................................ 47
TABLE 24: PIN DEFINITION OF SPI INTERFACE .......................................................................................... 48
TABLE 25: PIN DEFINITION OF GPIO INTERFACES..................................................................................... 48
TABLE 26: LOGIC LEVELS OF GPIO INTERFACES ...................................................................................... 48
TABLE 27: PIN DEFINITION OF GRFC INTERFACES.................................................................................... 49
TABLE 28: LOGIC LEVELS OF GRFC INTERFACES ..................................................................................... 49
TABLE 29: GNSS PERFORMANCE ................................................................................................................. 50
TABLE 30: PIN DEFINITION OF MAIN ANTENNA INTERFACE..................................................................... 52
TABLE 31: BG77 OPERATING FREQUENCY ................................................................................................. 52
TABLE 32: PIN DEFINITION OF GNSS ANTENNA INTERFACE.................................................................... 56
TABLE 33: GNSS FREQUENCY ...................................................................................................................... 56
TABLE 34: ANTENNA REQUIREMENTS......................................................................................................... 57
TABLE 35: ABSOLUTE MAXIMUM RATINGS ................................................................................................. 60
TABLE 36: POWER SUPPLY RATINGS .......................................................................................................... 60
TABLE 37: OPERATION AND STORAGE TEMPERATURES......................................................................... 61
TABLE 38: BG77 CURRENT CONSUMPTION ................................................................................................ 61
TABLE 39: BG77 RF OUTPUT POWER........................................................................................................... 64
TABLE 40: BG77 CONDUCTED RF RECEIVING SENSITIVITY ..................................................................... 64
TABLE 41: ELECTROSTATIC DISCHARGE CHARACTERISTICS (25ºC, 45% RELATIVE HUMIDITY) ....... 65

LPWA Module Series
BG77 Hardware Design
BG77_Hardware_Design 6/76
TABLE 42: RECOMMENDED THERMAL PROFILE PARAMETERS .............................................................. 71
TABLE 43: REEL PACKAGING ........................................................................................................................ 73
TABLE 44: RELATED DOCUMENTS ............................................................................................................... 74
TABLE 45: TERMS AND ABBREVIATIONS..................................................................................................... 74

LPWA Module Series
BG77 Hardware Design
BG77_Hardware_Design 7/76
Figure Index
FIGURE 1: FUNCTIONAL DIAGRAM ............................................................................................................... 14
FIGURE 2: PIN ASSIGNMENT (TOP VIEW) .................................................................................................... 16
FIGURE 3: SLEEP MODE APPLICATION VIA UART ...................................................................................... 28
FIGURE 4: STAR STRUCTURE OF THE POWER SUPPLY........................................................................... 29
FIGURE 5: TURN ON THE MODULE USING DRIVING CIRCUIT................................................................... 30
FIGURE 6: TURN ON THE MODULE USING KEYSTROKE ........................................................................... 31
FIGURE 7: TIMING OF TURNING ON MODULE ............................................................................................. 31
FIGURE 8: TIMING OF TURNING OFF MODULE ........................................................................................... 32
FIGURE 9: TIMING OF RESET MODULE........................................................................................................ 33
FIGURE 10: REFERENCE CIRCUIT OF RESET_N BY USING DRIVING CIRCUIT ...................................... 33
FIGURE 11: REFERENCE CIRCUIT OF RESET_N BY USING BUTTON ...................................................... 34
FIGURE 12: REFERENCE CIRCUIT OF PON_TRIG CIRCUIT ....................................................................... 35
FIGURE 13: REFERENCE CIRCUIT OF (U)SIM INTERFACE WITH AN 8-PIN (U)SIM CARD CONNECTOR
................................................................................................................................................................... 36
FIGURE 14: REFERENCE CIRCUIT OF (U)SIM INTERFACE WITH A 6-PIN (U)SIM CARD CONNECTOR 36
FIGURE 15: REFERENCE DESIGN OF USB PHY .......................................................................................... 38
FIGURE 16: REFERENCE DESIGN OF USB INTERFACE............................................................................. 38
FIGURE 17: REFERENCE CIRCUIT WITH TRANSLATOR CHIP................................................................... 41
FIGURE 18: REFERENCE CIRCUIT WITH TRANSISTOR CIRCUIT.............................................................. 42
FIGURE 19: REFERENCE CIRCUIT OF PCM APPLICATION WITH AUDIO CODEC ................................... 43
FIGURE 20: REFERENCE CIRCUIT OF THE NETWORK STATUS INDICATOR .......................................... 44
FIGURE 21: REFERENCE CIRCUIT OF STATUS........................................................................................... 45
FIGURE 22: REFERENCE CIRCUIT OF USB_BOOT INTERFACE................................................................ 46
FIGURE 23: REFERENCE CIRCUIT OF RF ANTENNA INTERFACE ............................................................ 54
FIGURE 24: MICROSTRIP LINE DESIGN ON A 2-LAYER PCB ..................................................................... 54
FIGURE 25: COPLANAR WAVEGUIDE LINE DESIGN ON A 2-LAYER PCB................................................. 55
FIGURE 26: COPLANAR WAVEGUIDE LINE DESIGN ON A 4-LAYER PCB (LAYER 3 AS REFERENCE
GROUND) .................................................................................................................................................. 55
FIGURE 27: COPLANAR WAVEGUIDE LINE DESIGN ON A 4-LAYER PCB (LAYER 4 AS REFERENCE
GROUND) .................................................................................................................................................. 55
FIGURE 28: REFERENCE CIRCUIT OF GNSS ANTENNA INTERFACE ....................................................... 57
FIGURE 29: DIMENSIONS OF THE U.FL-R-SMT CONNECTOR (UNIT: MM) ............................................... 58
FIGURE 30: MECHANICALS OF U.FL-LP CONNECTORS............................................................................. 59
FIGURE 31: SPACE FACTOR OF MATED CONNECTOR (UNIT: MM) .......................................................... 59
FIGURE 32: MODULE TOP AND SIDE DIMENSIONS .................................................................................... 66
FIGURE 33: MODULE BOTTOM DIMENSIONS (BOTTOM VIEW) ................................................................. 67
FIGURE 34: RECOMMENDED FOOTPRINT (TOP VIEW) .............................................................................. 68
FIGURE 35: TOP VIEW OF THE MODULE...................................................................................................... 69
FIGURE 36: BOTTOM VIEW OF THE MODULE.............................................................................................. 69
FIGURE 37: RECOMMENDED REFLOW SOLDERING THERMAL PROFILE ............................................... 71
FIGURE 38: TAPE DIMENSIONS..................................................................................................................... 72

LPWA Module Series
BG77 Hardware Design
BG77_Hardware_Design 8/76
FIGURE 39: REEL DIMENSIONS..................................................................................................................... 73

LPWA Module Series
BG77 Hardware Design
BG77_Hardware_Design 9/76
1Introduction
This document defines BG77 module and describes its air interface and hardware interfaces which are
connected with customers’ applications.
This document can help customers quickly understand the interface specifications, electrical and
mechanical details, as well as other related information of BG77. To facilitate its application in different
fields, reference design is also provided for customers’ reference. Associated with application notes and
user guides, customers can use the module to design and set up mobile applications easily.

LPWA Module Series
BG77 Hardware Design
BG77_Hardware_Design 10/76
1.1. Safety Information
The following safety precautions must be observed during all phases of the operation, such as usage,
service or repair of any cellular terminal or mobile incorporating BG77. Manufacturers of the cellular
terminal should send the following safety information to users and operating personnel, and incorporate
these guidelines into all manuals supplied with the product. If not so, Quectel assumes no liability for
customers’ failure to comply with these precautions.
Full attention must be given 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 the device offers an Airplane Mode, then it should be
enabled prior to boarding an aircraft. Please consult the airline staff for more
restrictions on the use of wireless devices on boarding the 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 signals and cellular network
cannot be guaranteed to connect in all possible conditions (for example, with
unpaid bills or with an invalid (U)SIM card). When emergent help is needed in such
conditions, please remember using emergency call. 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.
The cellular terminal or mobile contains a transmitter and receiver. When it is ON, it
receives and transmits radio frequency signals. RF interference can occur if it is
used close to TV set, radio, computer or other electric equipment.
In locations with potentially explosive atmospheres, obey all posted signs to turn
off wireless devices such as your phone or other cellular terminals. Areas with
potentially explosive atmospheres include fueling areas, below decks on boats,
fuel or chemical transfer or storage facilities, areas where the air contains
chemicals or particles such as grain, dust or metal powders, etc.

1.2 FCC Certification Requirements.
According to the definition of mobile and fixed device is described in Part 2.1091(b), this
device is a mobile device.
And the following conditions must be met:
1. This Modular Approval is limited to OEM installation for mobile and fixed applications
only. The antenna installation and operating configurations of this transmitter, including
any applicable source-based time- averaging duty factor, antenna gain and cable loss
must satisfy MPE categorical Exclusion Requirements of 2.1091.
2. The EUT is a mobile device; maintain at least a 20 cm separation between the EUT and
the user’s body and must not transmit simultaneously with any other antenna or
transmitter.
3.A label with the following statements must be attached to the host end product: This
device contains FCC ID: XMR201912BG77.
4.To comply with FCC regulations limiting both maximum RF output power and human
exposure to RF radiation, maximum antenna gain (including cable loss) must not
exceed:
❒Catm LTE Band2/25:≤11.000dBi
❒Catm LTE Band4/66:≤8.000dBi
❒Catm LTE Band5:≤12.416dBi
❒Catm LTE Band12:≤11.734dBi
❒Catm LTE Band13:≤12.173dBi
❒Catm LTE Band14:≤12.255 dBi
❒Catm LTE Band26:≤15.013 dBi
❒Catm LTE Band85:≤12.770 dBi
❒NB LTE Band2/25:≤11.000dBi
❒NB LTE Band4/66:≤8.000dBi
❒NB LTE Band5/26:≤15.013dBi

❒NB LTE Band12/85:≤12.416dBi
❒NB LTE Band13:≤11.734dBi
❒BNLTE Band14:≤12.272 dBi
❒NB LTE Band71:≤11.447 dBi
❒NB LTE Band85:≤12.770 dBi
5. This module must not transmit simultaneously with any other antenna or
transmitter
6. The host end product must include a user manual that clearly defines operating
requirements and conditions that must be observed to ensure compliance with current
FCC RF exposure guidelines.
For portable devices, in addition to the conditions 3 through 6 described above, a
separate approval is required to satisfy the SAR requirements of FCC Part 2.1093
If the device is used for other equipment that separate approval is required for all other
operating configurations, including portable configurations with respect to 2.1093 and
different antenna configurations.
For this device, OEM integrators must be provided with labeling instructions of finished
products. Please refer to KDB784748 D01 v07, section 8. Page 6/7 last two
paragraphs:
A certified modular has the option to use a permanently affixed label, or an electronic
label. For a permanently affixed label, the module must be labeled with an FCC ID -
Section 2.926 (see 2.2 Certification (labeling requirements) above). The OEM manual
must provide clear instructions explaining to the OEM the labeling requirements,
options and OEM user manual instructions that are required (see next paragraph).
For a host using a certified modular with a standard fixed label, if (1) the module’s FCC
ID is not visible when installed in the host, or (2) if the host is marketed so that end

users do not have straightforward commonly used methods for access to remove the
module so that the FCC ID of the module is visible; then an additional permanent label
referring to the enclosed module:“Contains Transmitter Module FCC ID:
XMR201912BG77” or “Contains FCC ID: XMR201912BG77” must be used. The host
OEM user manual must also contain clear instructions on how end users can find
and/or access the module and the FCC ID.
The final host / module combination may also need to be evaluated against the FCC
Part 15B criteria for unintentional radiators in order to be properly authorized for
operation as a Part 15 digital device.
The user’s manual or instruction manual for an intentional or unintentional radiator shall
caution the user that changes or modifications not expressly approved by the party
responsible for compliance could void the user's authority to operate the equipment. In
cases where the manual is provided only in a form other than paper, such as on a
computer disk or over the Internet, the information required by this section may be
included in the manual in that alternative form, provided the user can reasonably be
expected to have the capability to access information in that form.
This device complies with part 15 of the FCC Rules. Operation is subject to the
following two conditions: (1) This device may not cause harmful interference, and (2)
this device must accept any interference received, including interference that may
cause undesired operation.
Changes or modifications not expressly approved by the manufacturer could void the
user’s authority to operate the equipment.

LPWA Module Series
BG77 Hardware Design
BG77_Hardware_Design 11/76
2Product Concept
2.1. General Description
BG77 is an embedded IoT (LTE Cat M1, LTE Cat NB2) wireless communication module. It provides data
connectivity on LTE-FDD network, and supports half-duplex operation in LTE network. It also provides
GNSS and voice 1) functionality to meet customers’ specific application demands.
Table 1: Frequency Bands and GNSS Types of BG77 Module
1. 1) BG77 supports VoLTE (Voice over LTE) under LTE Cat M1. This voice function is still under
development.
2. 2) LTE Cat NB2 is backward compatible with LTE Cat NB1.
3. “*” means under development.
With a compact profile of 14.9mm × 12.9mm × 1.7mm, BG77 can meet almost all requirements for M2M
applications such as smart metering, tracking system, security, wireless POS, etc. It is especially suitable
for size and weight sensitive applications such as smart watch and other wearable devices.
BG77 is an SMD type module which can be embedded into applications through its 94 LGA pads. It
supports internet service protocols like TCP, UDP and PPP. Extended AT commands have been
developed for customers to use these internet service protocols easily.
Module Supported Bands LTE Bands Power Class GNSS
BG77
Cat M1:
LTE-FDD:
B1/B2/B3/B4/B5/B8/B12/B13/B14/B18/
B19/B20/B25/B26*/ B27/B28/B66/B85
Cat NB2 2):
LTE-FDD:
B1/B2/B3/B4/B5/B8/B12/B13/B18/B19/
B20/B25/B26*/B28/B66/B71/B85
Power Class 5 (21dBm)
GPS, GLONASS,
BeiDou, Galileo,
QZSS
NOTES

LPWA Module Series
BG77 Hardware Design
BG77_Hardware_Design 12/76
2.2. Key Features
The following table describes the detailed features of BG77 module.
Table 2: Key Features of BG77 Module
Features Details
Power Supply
Supply voltage: 2.6V~4.8V
Typical supply voltage: 3.3V
Transmitting Power Class 5 (21dBm+1/-3dB) for LTE-FDD bands
LTE Features
Support 3GPP Rel. 14
Support LTE Cat M1 and LTE Cat NB2
Support 1.4MHz RF bandwidth for LTE Cat M1
Support 200KHz RF bandwidth for LTE Cat NB2on
Cat M1: Max. 588Kbps (DL)/1119Kbps (UL)
Cat NB2: Max. 127Kbps (DL)/158.5Kbps (UL)
Internet Protocol
Features
Support PPP/TCP/UDP/SSL/TLS/FTP(S)/HTTP(S)/NITZ/PING/MQTT/
CoAP protocols
Support PAP (Password Authentication Protocol) and CHAP
(Challenge Handshake Authentication Protocol) protocols which are
usually used for PPP connections
SMS
Text and PDU mode
Point to point MO and MT
SMS cell broadcast
SMS storage: ME by default
(U)SIM Interface Support 1.8V USIM/SIM card only
Audio Feature Support one digital audio interface: PCM interface*
USB Interface
Compliant with USB 2.0 specification (slave only)
Support operations at low-speed and full-speed
Used for AT command communication, data transmission, GNSS
NMEA output, software debugging and firmware upgrade
Support USB serial drivers for Windows 7/8/8.1/10, Linux 2.6/3.x (3.4
or later)/4.1~4.15, Android 4.x/5.x/6.x/7.x/8.x/9.x
UART Interfaces
Main UART:
Used for data transmission and AT command communication
115200bps baud rate by default
The default frame format is 8N1 (8 data bits, no parity, 1 stop bit)
Support RTS and CTS hardware flow control
Debug UART:

LPWA Module Series
BG77 Hardware Design
BG77_Hardware_Design 13/76
1. “*” means under development.
2. 1) Within operation temperature range, the module is 3GPP compliant.
3. 2) Within extended temperature range, the module remains the ability to establish and maintain a
voice, SMS, data transmission, emergency call, etc. There is no unrecoverable malfunction. There
are also no effects on radio spectrum and no harm to radio network. Only one or more parameters like
Pout might reduce in their value and exceed the specified tolerances. When the temperature returns to
the normal operating temperature levels, the module will meet 3GPP specifications again.
2.3. Functional Diagram
The following figure shows a block diagram of BG77 and illustrates the major functional parts.
Power management
Baseband
Radio frequency
Peripheral interfaces
Used for software debugging and log output
Support 115200bps baud rate
GNSS UART:
Used for GNSS data and NMEA sentences output
115200bps baud rate by default
AT Commands 3GPP TS 27.007 and 3GPP TS 27.005 AT commands, as well as Quectel
enhanced AT commands
Network Indication One NETLIGHT pin for network connectivity status indication
Antenna Interfaces Main antenna (ANT_MAIN) and GNSS antenna (ANT_GNSS) interfaces
Physical Characteristics
Size: (14.9±0.15)mm × (12.9±0.15)mm × (1.7±0.2)mm
Weight: approx. 0.73g
Temperature Range
Operation temperature range: -35°C ~ +75°C 1)
Extended temperature range: -40°C ~ +85°C 2)
Storage temperature range: -40°C ~ +90°C
Firmware Upgrade USB interface and DFOTA*
RoHS All hardware components are fully compliant with EU RoHS directive
NOTES

LPWA Module Series
BG77 Hardware Design
BG77_Hardware_Design 14/76
Baseband
PMIC
Transceiver/PA/switch
ANT_MAIN ANT_GNSS
VBAT
PWRKEY
VDD_EXT USB (U)SIM PCM I2C
19.2M
XO
GPIOs
Control
IQ Control
SAW+LNA
GNSS
UARTs
ADC0
STATUS NETLIGHT
RESET_N
ADC1
SPI
PON_TRIG
COUPLER
Figure 1: Functional Diagram
1. PWRKEY output voltage is 1.5V because of the voltage drop inside the Qualcomm chipset. Due to
platform limitations, the chipset has integrated the reset function into PWRKEY. Therefore, PWRKEY
should never be pulled down to GND permanently.
2. RESET_N is multiplexed from PWRKEY.
2.4. Evaluation Board
In order to help customers to develop applications conveniently with BG77, Quectel supplies the
evaluation board (EVB), USB to RS-232 converter cable, USB data cable, earphone, antenna and other
peripherals to control or test the module. For more details, please refer to document [1].
NOTES

LPWA Module Series
BG77 Hardware Design
BG77_Hardware_Design 15/76
3Application Interfaces
BG77 is equipped with 94 LGA pads that can be connected to customers’ cellular application platforms.
The following sub-chapters will provide detailed description of interfaces listed below:
Power supply
(U)SIM interface
USB interface
UART interfaces
PCM and I2C interfaces*
Status indication
USB_BOOT interface
ADC interfaces
GPIO interfaces*
GRFC interfaces*
“*” means under development.
NOTE

LPWA Module Series
BG77 Hardware Design
BG77_Hardware_Design 16/76
3.1. Pin Assignment
The following figure shows the pin assignment of BG77.
38
38 RTS 77 AP_READY
32 31 30 29 28 27 26
53545556
1
2
3
4
5
6
7
8
9
40
39
37
36
35
34
33
57
58
59
60
61
62
63
73
74
75
76
77
78
89
88
87
86
85 94
93
92
91
90
79
80
81
82
83
84
71
70
69
68
67
66
65
45
46
47
48
49
50
51
52
25
24
23
22
21
20
19
18
17
72
41 42
64
43 44
10 11 12 13 14 15 16
60 DBG_TXD
1 GP IO1
5 I2C_SDA
UART
33 GP IO2
34 PCM_DOUT
35 PC M_SY NC
36 GNSS_TXD
37 I2C_SCL
39 CTS
40 SP I_MOSI
ANT GND
26
ANT_MAIN
32
ANT_GNSS
57 GP IO3
61 DBG_RXD
62 DTR
63 SP I_CS
78 STA TU S
76 RI
87 USB_BO OT
I2C SP I
DCD 90
NETLIGHT 79
ADC1 18
10
USB_DM
11
USB_DP
12
USB_VBUS 4)
13
USIM_CLK
14
USIM_DATA
15
USIM_RST
16
USIM_VDD
44
USIM_DET
42
USB_VDDA_3P3
64
EX T_PWR_EN
ADC0 17
VBAT 19
VBAT 20
VDD_EXT 21
USBUSIM
PO WER
2 PCM_DIN
3 PCM_CLK
4 GNSS_RXD
6 RXD
7 TXD
8 SP I_MISO
9 SP I_CLK
USB PCM RESE RVED OTHERS
41
W_DISA BLE #
RESE T_N 45
PWRKEY 46
USIM_GND 65
72
PO N_T RIG
GR FC2 94
GR FC1 83
Figure 2: Pin Assignment (Top View)
1. PWRKEY output voltage is 1.5V because of the voltage drop inside the Qualcomm chipset. Due to
platform limitations, the chipset has integrated the reset function into PWRKEY. Therefore, PWRKEY
should never be pulled down to GND permanently.
2. RESET_N is multiplexed from PWRKEY .
NOTES