Quectel BC660K-GL User manual

BC660K-GL
Hardware Design
NB-IoT Module Series
Version: 1.0
Date: 2021-01-12
Status: Released
www.quectel.com

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General Notes
Quectel offers the information as a service to its customers. The information provided is based upon
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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.
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Copyright
The information contained here is proprietary technical information of Quectel. 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 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
-
2020-09-30
Clifton HE/
Ellison WANG/
Randy LI
Creation of the document
1.0
2021-01-12
Clifton HE/
Ellison WANG/
Randy LI
First official release

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Contents
Safety Information...................................................................................................................................... 3
About the Document.................................................................................................................................. 4
Contents...................................................................................................................................................... 5
Table Index.................................................................................................................................................. 7
Figure Index................................................................................................................................................ 8
1Introduction......................................................................................................................................... 9
2Product Concept............................................................................................................................... 10
2.1. General Description................................................................................................................. 10
2.2. Key Features............................................................................................................................ 11
2.3. Functional Diagram.................................................................................................................. 12
2.4. Evaluation Board...................................................................................................................... 13
3Application Functions and Interfaces ............................................................................................ 14
3.1. Pin Assignment........................................................................................................................ 15
3.2. Pin Description......................................................................................................................... 16
3.3. Operating Modes...................................................................................................................... 19
3.4. Power Saving........................................................................................................................... 20
3.4.1. Light Sleep.................................................................................................................... 20
3.4.2. Deep Sleep................................................................................................................... 21
3.5. Power Supply........................................................................................................................... 22
3.5.1. Power Supply Pins........................................................................................................ 22
3.5.2. Power Supply Reference Design.................................................................................. 22
3.5.3. Power Supply Voltage Detection.................................................................................. 23
3.6. Turn-on/Turn-off Scenario........................................................................................................ 23
3.6.1. Turn On......................................................................................................................... 23
3.6.2. Turn Off......................................................................................................................... 24
3.6.3. Reset............................................................................................................................. 24
3.6.4. Download Mode............................................................................................................ 25
3.7. UART Interfaces....................................................................................................................... 26
3.7.1. Main UART Port............................................................................................................ 27
3.7.2. Debug UART Port......................................................................................................... 27
3.7.3. UART Application ......................................................................................................... 28
3.8. USIM Interface......................................................................................................................... 30
3.9. ADC Interface........................................................................................................................... 32
3.10. RI Interface............................................................................................................................... 32
3.11. GPIO Interfaces ....................................................................................................................... 33
3.12. GRFC Interfaces*..................................................................................................................... 34
3.13. NETLIGHT Interface*............................................................................................................... 34
4Antenna Interface.............................................................................................................................. 35
4.1. Pin Definition............................................................................................................................ 35

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4.2. Operating Frequency............................................................................................................... 35
4.3. RF Antenna Reference Design................................................................................................ 36
4.4. Reference Design of RF Layout .............................................................................................. 37
4.5. Antenna Requirements............................................................................................................ 38
4.6. RF Output Power ..................................................................................................................... 39
4.7. RF Receiving Sensitivity.......................................................................................................... 40
4.8. Recommended RF Connector for Antenna Installation........................................................... 41
5Reliability and Electrical Characteristics....................................................................................... 43
5.1. Operating and Storage Temperatures..................................................................................... 43
5.2. Current Consumption............................................................................................................... 43
5.3. Electrostatic Discharge............................................................................................................ 46
6Mechanical Features......................................................................................................................... 47
6.1. Mechanical Dimensions........................................................................................................... 47
6.2. Recommended Footprint ......................................................................................................... 49
6.3. Top and Bottom Views............................................................................................................. 50
7Storage, Manufacturing and Packaging......................................................................................... 51
7.1. Storage..................................................................................................................................... 51
7.2. Manufacturing and Soldering................................................................................................... 52
7.3. Tape and Reel Packaging........................................................................................................ 53
8Appendix References....................................................................................................................... 55

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Table Index
Table 1: Frequency Bands of BC660K-GL................................................................................................10
Table 2: Key Features of BC660K-GL.......................................................................................................11
Table 3: I/O Parameters Definition............................................................................................................. 16
Table 4: Pin Description............................................................................................................................. 16
Table 5: Application Processor (AP) Operating Modes............................................................................. 20
Table 6: Modem Operating Modes ............................................................................................................20
Table 7: Module Operating Modes............................................................................................................. 20
Table 8: Power Supply Pins....................................................................................................................... 22
Table 9: Reset Pin Definition...................................................................................................................... 24
Table 10: Boot Pin Definition...................................................................................................................... 25
Table 11: Pin Definition of UART Interfaces.............................................................................................. 26
Table 12: Pin Definition of USIM Interface................................................................................................. 30
Table 13: Pin Definition of ADC Interface..................................................................................................32
Table 14: Pin Definition of RI Interface......................................................................................................32
Table 15: RI Signal Status .........................................................................................................................33
Table 16: Pin Definition of GPIO Interfaces...............................................................................................33
Table 17: Pin Definition of GRFC Interfaces.............................................................................................. 34
Table 18: Pin Definition of NETLIGHT Interface........................................................................................34
Table 19: Pin Definition of NB-IoT Antenna Interface................................................................................35
Table 20: Module Operating Frequency....................................................................................................35
Table 21: Antenna Cable Insertion Loss Requirements............................................................................38
Table 22: Required Antenna Parameters..................................................................................................39
Table 23: RF Conducted Output Power..................................................................................................... 39
Table 24: RF Receiving Sensitivity............................................................................................................40
Table 25: Operating and Storage Temperatures.......................................................................................43
Table 26: Module Current Consumption (3.3 V VBAT Power Supply)......................................................44
Table 27: Electrostatic Discharge Characteristics (25 ºC, 45 % Relative Humidity).................................46
Table 28: Recommended Thermal Profile Parameters............................................................................. 53
Table 29: Related Documents....................................................................................................................55
Table 30: Terms and Abbreviations........................................................................................................... 55

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Figure Index
Figure 1: Functional Diagram.....................................................................................................................13
Figure 2: Pin Assignment...........................................................................................................................15
Figure 3: Module Power Consumption in Different Modem Modes...........................................................21
Figure 4: Timing of Waking Up Module from PSM....................................................................................22
Figure 5: Reference Design for Power Supply .......................................................................................... 23
Figure 6: Turn-on Timing............................................................................................................................ 23
Figure 7: Turn-off Timing............................................................................................................................ 24
Figure 8: Reference Design for RESET_N Controlled with an OC/OD Driving Circuit............................. 25
Figure 9: Reference Design for RESET_N Controlled with a Button ........................................................ 25
Figure 10: Reference Design for BOOT Controlled with a Button............................................................. 26
Figure 11: Reference Design for Main UART Port....................................................................................27
Figure 12: Reference Design for Debug UART Port..................................................................................28
Figure 13: Reference Design for UART.....................................................................................................28
Figure 14: Reference Design for Module-PC Communication via RS-232 Interface................................ 29
Figure 15: Reference Design for Level Conversion Circuit .......................................................................30
Figure 16: Reference Design for USIM Interface with a 6-pin USIM Card Connector.............................. 31
Figure 17: RI Behaviour When a URC/Message is Received...................................................................33
Figure 18: Reference Design for NETLIGHT............................................................................................. 34
Figure 19: Reference Design for NB-IoT Antenna Interface......................................................................36
Figure 20: Microstrip on a 2-layer PCB......................................................................................................37
Figure 21: Coplanar Waveguide on a 2-layer PCB.................................................................................... 37
Figure 22: Coplanar Waveguide on a 4-layer PCB (Layer 3 as Reference Ground)................................37
Figure 23: Coplanar Waveguide on a 4-layer PCB (Bottom Layer as Reference Ground).......................38
Figure 24: Dimensions of the U.FL-R-SMT Connector (Unit: mm)............................................................ 41
Figure 25: Mechanicals of U.FL-LP Connectors........................................................................................ 42
Figure 26: Space Factor of Mated Connectors (Unit: mm)........................................................................ 42
Figure 27: Top and Side Dimensions (Unit: mm).......................................................................................47
Figure 28: Bottom Dimension (Bottom View)............................................................................................. 48
Figure 29: Recommended Footprint (Unit: mm)........................................................................................ 49
Figure 30: Top View of the Module............................................................................................................50
Figure 31: Bottom View of the Module....................................................................................................... 50
Figure 32: Recommended Reflow Soldering Thermal Profile ...................................................................52
Figure 33: Tape Dimensions (Unit: mm)....................................................................................................54
Figure 34: Reel Dimensions (Unit: mm).....................................................................................................54

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1Introduction
This document provides information on the functional features, interface specifications, as well as
electrical and mechanical details of the BC660K-GL module. Consult this document to learn about the air
interface, hardware interface, external application reference designs and other related information of the
module.
This document, coupled with application notes and user guides, makes it easy to design and set up
applications with BC660K-GL.

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2Product Concept
2.1. General Description
BC660K-GL is a high-performance NB-IoT module with extremely low power consumption. It is designed
to communicate with infrastructures of mobile network operators through NB-IoT radio protocols 3GPP
Rel-13 and Rel-14. BC660K-GL supports a broad range of frequency bands as listed below.
Table 1: Frequency Bands of BC660K-GL
BC660K-GL is an SMD type module with LCC and LGA package, and has an ultra-compact profile of
17.7 mm ×15.8 mm ×2.0 mm, which makes it easily embedded into size-constrained applications and
provide reliable connectivity with the applications.
BC660K-GL provides abundant external interfaces (UART, ADC, USIM, etc.) and protocol stacks
(UDP/TCP/LwM2M*/MQTT*, etc.), which facilitates the module’s application.
The module’s compact form factor, ultra-low power consumption and extended temperature range makes
it one of the best choices for a wide range of IoT application, such as smart metering, bike sharing, smart
wearables, smart parking, smart city, home appliances, security and asset tracking, agricultural and
environmental monitoring, etc. It also provides a complete range of SMS* and data transmission services
to meet various user demands.
The module fully complies with the RoHS directive of the European Union.
“*” means under development.
Mode
BC660K-GL
H-FDD
B1/B2/B3/B4/B5/B8/B12/B13/B14/B17/B18/B19/B20/B25/B28/B66/B70/B85
NOTE

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2.2. Key Features
The following table describes the detailed features of BC660K-GL module.
Table 2: Key Features of BC660K-GL
Item
Details
Power Supply
⚫Supply voltage: 2.2–4.3 V
⚫Typical supply voltage: 3.3 V
Power Saving
Typical power consumption: 800 nA
Frequency Bands
LTE Cat NB2:
B1/B2/B3/B4/B5/B8/B12/B13/B14/B17/B18/B19/B20/B25/B28/B66/B70/B85
Transmitting Power
23 dBm ±2 dB
USIM Interface
Support 1.8/3.0 V USIM card
UART Interfaces
Main UART Port:
⚫Used for AT command communication and data transmission, where the
baud rate is 115200 bps by default. For more details, see Chapter 3.7.1.
⚫Used for firmware upgrade, where the baud rate is 921600 bps by
default.
Debug UART Port:
⚫Used for debugging
⚫Default baud rate: 6 Mbps
Network Protocols
UDP/TCP/SNTP/LwM2M*/MQTT*/TLS*/DTLS*/SSL*
SMS*
⚫Text Mode
⚫PDU Mode
Data Transmission
Features
⚫Single-tone (max): 25.5 kbps (DL)/16.7 kbps (UL)
⚫Multi-tone (max): 127 kbps (DL)/158.5 kbps (UL)
AT Commands
⚫3GPP TS 27.005/3GPP TS 27.007 AT commands (3GPP Rel-13)
⚫Quectel enhanced AT commands
Firmware Update
⚫Upgrade firmware via main UART port
⚫Upgrade firmware via DFOTA
Real Time Clock
Supported
Physical Characteristics
⚫Size: (17.7 ±0.15) mm ×(15.8 ±0.15) mm ×(2.0 ±0.2) mm
⚫Weight: 1.0 ±0.2 g
Temperature Range
⚫Operating temperature range: -35 to +75 °C 1)
⚫Extended temperature range: -40 to +85 °C 2)
⚫Storage temperature range: -40 to +90 °C

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1. 1) Within operating temperature range, the module is 3GPP compliant.
2. 2) Within extended temperature range, the module maintains functions such as SMS and data
transmission, without any unrecoverable malfunction. Radio spectrum and radio network will not be
influenced, while one or more specifications, such as Pout, may exceed the specified tolerances of
3GPP. When the temperature returns to the normal operating temperature levels, the module will
meet 3GPP specifications again.
3. "*" means under development.
2.3. Functional Diagram
The following figure shows a block diagram of BC660K-GL and illustrates the major functional parts.
⚫RF Transceiver and Subsystem
⚫Baseband
⚫Power Management Unit
⚫Peripheral Interfaces
Antenna Interface
50 Ω impedance control
RoHS
All hardware components are fully compliant with EU RoHS directive
NOTES

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ANT_RF
PMU
DC-DC RF Transceiver
and Subsystem
XO
26 MHz
XTAL
Baseband
RESET_N
ADC
MAIN_UART
Flash
SRAM
NETLIGHT
32 kHz
RTC BLOCK
LDO
PSM_EINT
USIM
BOOT
DBG_UART
USIM
VBAT
VDD_EXT
eSIM
RI
Switch
LB TX LPM
LB TX HPM
HB TX LPM
HB TX HPM
HB RX
LB RX
GPIOs
GRFC
VIO_SEL
Figure 1: Functional Diagram
2.4. Evaluation Board
Quectel provides a complete set of development tools to facilitate the use and testing of BC660K-GL
module. The development tool kit includes a TE-B board, a micro-USB cable, a rod antenna and other
peripherals. For more details, see document [1].

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3Application Functions and Interfaces
BC660K-GL is equipped with 58 pins, including 44 LCC pins and 14 LGA pins. The subsequent chapters
provide detailed descriptions of the following functions/pins/interfaces:
⚫Power Supply
⚫PSM_EINT
⚫RESET_N
⚫BOOT
⚫UART Interfaces
⚫USIM Interface
⚫ADC Interface
⚫RI Interface
⚫GPIO interfaces
⚫GRFC interfaces*
⚫NETLIGHT Interface*
"*" means under development.
NOTE

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3.1. Pin Assignment
15 16 17 18 19 20
21 22 36
37 38 39 40 41 42 43 44
1
2
3
4
5
6
7
8
9
10
11
12
13 23
24
25
26
27
28
29
30
31
32
33
34
35
RESERVED
ADC0
USIM_GND
USIM_DATA
GND
RESERVED
RESERVED
RESERVED
RESERVED
GND
RESERVED
RESERVED
VDD_EXT
RESERVED
RESERVED
RI
PSM_EINT
MAIN_RXD
MAIN_TXD
NETLIGHT
RESET_N
USIM_VDD
VBAT
Power GND UART USIM ANT RESERVED
45
46
47
48
49 50 51
52
53
54
55
565758
VBAT GND
14
ANT_RF
GND GND GND RESERVED DBG_TXD DBG_RXD
USIM_RST
USIM_CLK
RESERVED
BOOT
RESERVED
GND
GRFC
BC660K-GL
Top View
GPIO1
GPIO3
GPIO4
Others
RESERVED
RESERVED
GRFC2
VIO_SEL
GPIO2
GRFC1
Figure 2: Pin Assignment
Keep all reserved and unused pins unconnected.
NOTE

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3.2. Pin Description
Table 3: I/O Parameters Definition
Table 4: Pin Description
Type
Description
AI
Analog Input
DI
Digital Input
DO
Digital Output
DIO
Digital Input/Output
PI
Power Input
PO
Power Output
Power Supply
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
VBAT
42, 43
PI
Power supply for
the module
Vmax = 4.3 V
Vmin = 2.2 V
Vnom = 3.3 V
-
VDD_EXT
24
PO
1.8/3.3 V output
power supply
(Controlled by
VIO_SEL, 1.8 V
default)
Vnom = 1.8/3.3 V
No voltage output in
Deep Sleep/Light
Sleep mode.
It is intended to supply
power for the module’s
pull-up circuits, and is
not recommended to
be used as the power
supply for external
circuits.
GND
1, 27, 34, 36, 37, 40, 41, 56, 57, 58
-
BOOT interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
BOOT
7
DI
Make the
module enter
VILmax = 0.2 ×VDD_EXT
VIHmin = 0.7 ×VDD_EXT
Active low.

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download mode
Reset Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
RESET_N
15
DI
Reset the
module
VILmax = 0.42 V
VIHmin = 1.33 V
VIHmax = 2.2 V
Active low.
PSM_EINT Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
PSM_EINT
19
DI
External interrupt
pin dedicated to
waking up the
module from
Deep/Light
Sleep mode.
VILmax = 0.42 V
VIHmin = 1.33 V
VIHmax = 2.2 V
Active on falling
edge.
Network Status Indication*
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
NETLIGHT
16
DO
Indicate the
module's
network activity
status
VOLmax = 0.15 ×VDD_EXT
VOHmin = 0.8 ×VDD_EXT
-
ADC Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
ADC0
9
AI
General-purpose
analog to digital
converter
interface
Voltage range:
0–1.2 V
-
Main UART Port
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
MAIN_RXD
18
DI
Main UART
receive
VILmax = 0.2 ×VDD_EXT
VIHmin = 0.7 ×VDD_EXT
-
MAIN_TXD
17
DO
Main UART
transmit
VOLmax = 0.15 ×VDD_EXT
VOHmin = 0.8 ×VDD_EXT
VDD_EXT
power domain.
Debug UART Port
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment

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DBG_RXD
38
DI
Debug UART
receive
VILmax = 0.2 ×VDD_EXT
VIHmin = 0.7 ×VDD_EXT
VDD_EXT
power domain.
DBG_TXD
39
DO
Debug UART
transmit
VOLmax = 0.15 ×VDD_EXT
VOHmin = 0.8 ×VDD_EXT
RI Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
RI
20
DO
Ring indication
VOLmax = 0.15 ×VDD_EXT
VOHmin = 0.8 ×VDD_EXT
VDD_EXT
power domain.
USIM Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
USIM_VDD
14
PO
USIM card
power supply
Vnom = 1.8/3.0 V
-
USIM_CLK
13
DO
USIM card clock
VOLmax = 0.15 ×USIM_VDD
VOHmin = 0.8 ×USIM_VDD
USIM_RST
12
DO
USIM card reset
VOLmax = 0.15 ×USIM_VDD
VOHmin = 0.8 ×USIM_VDD
USIM_DATA
11
DIO
USIM card data
VILmax = 0.2 ×USIM_VDD
VIHmin = 0.7 ×USIM_VDD
VOLmax = 0.15 ×USIM_VDD
VOHmin = 0.8 ×USIM_VDD
USIM_GND
10
Dedicated
ground for
USIM card
-
Antenna Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
ANT_RF
35
DIO
RF antenna
interface
-
50 Ω
characteristic
impedance
GPIO Interfaces
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
GPIO1
3
DIO
General-purpose
input/output
VILmax = 0.2 ×VDD_EXT
VIHmin = 0.7 ×VDD_EXT
VOLmax = 0.15 ×VDD_EXT
VOHmin = 0.8 ×VDD_EXT
VDD_EXT
power domain.
If unused, keep
these pins open.
GPIO2
4
DIO
General-purpose
input/output
GPIO3
5
DIO
General-purpose
input/output

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1. Keep all reserved and unused pins unconnected.
2. 1) When VIO_SEL is grounded and VBAT ˂3.3 V, VDD_EXT = VBAT;
When VIO_SEL is grounded and VBAT ≥ 3.3 V, VDD_EXT = 3.3 V;
When VIO_SEL is floating, VDD_EXT = 1.8 V.
3. “*” means under development.
3.3. Operating Modes
The following table briefly describes the three working modes of the module.
GPIO4
6
DIO
General-purpose
input/output
GRFC Interfaces*
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
GRFC1
54
DO
Generic RF
controller
VOLmax = 0.27 V
VOHmin = 1.44 V
1.8 V power
domain.
If unused, keep
these pins open.
GRFC2
55
DO
Generic RF
controller
VOLmax = 0.27 V
VOHmin = 1.44 V
Others
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
VIO_SEL
52
DI
IO Voltage
selection
-
Control
VDD_EXT
voltage
selection1)
Reserved Pins
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
RESERVED
2, 8, 21–23, 25, 26, 28–33, 44–51, 53
Keep these pins
open.
NOTES