Quectel BC66-NA User manual

BC66-NA Hardware
Design
NB-IoT Module Series
Rev. BC66-NA_Hardware_Design_V1.0
Date: 2019-11-05
Status: Released
www.quectel.com

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About the Document
History
Revision
Date
Author
Description
1.0
2019-11-05
Speed SUN/
Lewis SHEN/
Allan LIANG
Initial

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Contents
About the Document...................................................................................................................................2
Contents.......................................................................................................................................................3
Table Index...................................................................................................................................................5
Figure Index.................................................................................................................................................6
1Introduction..........................................................................................................................................7
1.1. Safety Information.......................................................................................................................8
2Product Concept..................................................................................................................................9
2.1. General Description....................................................................................................................9
2.2. Key Features.............................................................................................................................10
2.3. Functional Diagram................................................................................................................... 11
2.4. Development Board..................................................................................................................12
3Application Interfaces .......................................................................................................................13
3.1. General Description..................................................................................................................13
3.2. Pin Assignment .........................................................................................................................14
3.3. Pin Description..........................................................................................................................15
3.4. Operating Modes.......................................................................................................................18
3.4.1. Deep Sleep.....................................................................................................................19
3.5. Power Supply............................................................................................................................21
3.5.1. Power Supply Pins.........................................................................................................21
3.5.2. Reference Design for Power Supply..............................................................................21
3.6. Power up/down Scenarios........................................................................................................22
3.6.1. Turn on...........................................................................................................................22
3.6.2. Turn off...........................................................................................................................23
3.6.3. Reset the Module...........................................................................................................24
3.7. USB Interface............................................................................................................................26
3.8. UART Interfaces........................................................................................................................27
3.8.1. Main UART Port.............................................................................................................28
3.8.2. Debug UART Port ..........................................................................................................28
3.8.3. Auxiliary UART Port .......................................................................................................29
3.8.4. UARTApplication...........................................................................................................29
3.9. USIM Interface..........................................................................................................................31
3.10. ADC Interface............................................................................................................................33
3.11. RI Behaviors..............................................................................................................................33
3.12. Network Status Indication .........................................................................................................34
4Antenna Interface...............................................................................................................................35
4.1. Pin Definition.............................................................................................................................35
4.2. Operating Frequencies .............................................................................................................35
4.3. RFAntenna Reference Design.................................................................................................36
4.4. Reference Design of RF Layout ...............................................................................................37

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4.5. Antenna Requirements.............................................................................................................39
4.6. RF Output Power ......................................................................................................................40
4.7. RF Receiving Sensitivity...........................................................................................................41
4.8. Recommended RF Connector for Antenna Installation............................................................42
5Electrical and Reliability Characteristics........................................................................................44
5.1. Operation and Storage Temperatures.......................................................................................44
5.2. Current Consumption................................................................................................................44
5.3. Electrostatic Discharge.............................................................................................................47
6Mechanical Dimensions....................................................................................................................48
6.1. Mechanical Dimensions of the Module.....................................................................................48
6.2. Recommended Footprint ..........................................................................................................50
6.3. Top and Bottom Views of the Module.......................................................................................51
7Storage, Manufacturing and Packaging..........................................................................................52
7.1. Storage......................................................................................................................................52
7.2. Manufacturing and Soldering....................................................................................................53
7.3. Packaging .................................................................................................................................54
7.3.1. Tape and Reel Packaging..............................................................................................54
8Appendix A References.....................................................................................................................56

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Table Index
TABLE 1: FREQUENCY BANDS OF BC66-NA MODULE.................................................................................. 9
TABLE 2: BC66-NA KEY FEATURES ............................................................................................................... 10
TABLE 3: I/O PARAMETERS DEFINITION....................................................................................................... 15
TABLE 4: PIN DESCRIPTION........................................................................................................................... 15
TABLE 5: AP OPERATING MODES.................................................................................................................. 19
TABLE 6: MODEM OPERATING MODES ........................................................................................................ 19
TABLE 7: MODULE OPERATING MODES....................................................................................................... 19
TABLE 8: POWER SUPPLY PINS..................................................................................................................... 21
TABLE 9: PWRKEY PIN.................................................................................................................................... 22
TABLE 10: RESET PIN DEFINITION................................................................................................................ 24
TABLE 11: PIN DEFINITION OF USB INTERFACE.......................................................................................... 26
TABLE 12: PIN DEFINITION OF UART INTERFACES..................................................................................... 27
TABLE 13: PIN DEFINITION OF USIM INTERFACE........................................................................................ 32
TABLE 14: PIN DEFINITION OF ADC INTERFACE ......................................................................................... 33
TABLE 15: RI SIGNAL STATUS........................................................................................................................ 33
TABLE 16: MODULE STATUS INDICATED BY NETLIGHT ............................................................................. 34
TABLE 17: PIN DEFINITION OF NB-IOTANTENNA INTERFACE................................................................... 35
TABLE 18: MODULE OPERATING FREQUENCIES........................................................................................ 35
TABLE 19: ANTENNA CABLE INSERTION LOSS REQUIREMENTS ............................................................. 39
TABLE 20: REQUIRED ANTENNA PARAMETERS.......................................................................................... 39
TABLE 21: RF CONDUCTED OUTPUT POWER............................................................................................. 40
TABLE 22: RECEIVING SENSITIVITY (WITH RF RETRANSMISSIONS)....................................................... 41
TABLE 23: OPERATION AND STORAGE TEMPERATURES.......................................................................... 44
TABLE 24: MODULE CURRENT CONSUMPTION (3.3V VBAT POWER SUPPLY)........................................ 45
TABLE 25: ELECTROSTATIC DISCHARGE CHARACTERISTICS (25ºC, 45% RELATIVE HUMIDITY)........ 47
TABLE 26: RECOMMENDED THERMAL PROFILE PARAMETERS............................................................... 53
TABLE 27: RELATED DOCUMENTS................................................................................................................ 56
TABLE 28: TERMS AND ABBREVIATIONS...................................................................................................... 56

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Figure Index
FIGURE 1: FUNCTIONAL DIAGRAM ............................................................................................................... 12
FIGURE 2: PIN ASSIGNMENT ......................................................................................................................... 14
FIGURE 3: MODULE POWER CONSUMPTION IN DIFFERENT MODES (MODEM) .................................... 20
FIGURE 4: TIMING OF WAKING UP MODULE FROM DEEP SLEEP ............................................................ 20
FIGURE 5: REFERENCE CIRCUIT FOR POWER SUPPLY............................................................................ 22
FIGURE 6: TURN ON THE MODULE USING DRIVING CIRCUIT................................................................... 22
FIGURE 7: TURN ON THE MODULE USING KEYSTROKE ........................................................................... 23
FIGURE 8: POWER UP TIMING....................................................................................................................... 23
FIGURE 9: POWER DOWN TIMING (POWER OFF BY AT COMMAND)........................................................ 24
FIGURE 10: POWER DOWN TIMING (POWER OFF BY DISCONNECTING VBAT)...................................... 24
FIGURE 11: REFERENCE CIRCUIT OF RESET BY USING DRIVING CIRCUIT ........................................... 25
FIGURE 12: REFERENCE CIRCUIT OF RESET BY USING BUTTON........................................................... 25
FIGURE 13: RESET TIMING............................................................................................................................. 25
FIGURE 14: USB INTERFACE REFERENCE DESIGN................................................................................... 26
FIGURE 15: REFERENCE DESIGN FOR MAIN UART PORT......................................................................... 28
FIGURE 16: REFERENCE DESIGN OF DEBUG UART PORT ....................................................................... 29
FIGURE 17: REFERENCE DESIGN OF AUXILIARY UART PORT.................................................................. 29
FIGURE 18: REFERENCE CIRCUIT WITH VOLTAGE LEVEL TRANSLATOR CHIP...................................... 30
FIGURE 19: REFERENCE CIRCUIT WITH TRANSISTOR CIRCUIT.............................................................. 30
FIGURE 20: SKETCH MAP FOR RS-232 INTERFACE MATCH...................................................................... 31
FIGURE 21: REFERENCE CIRCUIT FOR USIM INTERFACE WITH A 6-PIN USIM CARD CONNECTOR... 32
FIGURE 22: BEHAVIORS OF RI WHEN AURC OR SMS MESSAGE IS RECEIVED..................................... 34
FIGURE 23: REFERENCE DESIGN OF NETLIGHT........................................................................................ 34
FIGURE 24: REFERENCE DESIGN OF NB-IOT ANTENNA INTERFACE ...................................................... 37
FIGURE 25: MICROSTRIP LINE DESIGN ON A 2-LAYER PCB...................................................................... 37
FIGURE 26: COPLANAR WAVEGUIDE LINE DESIGN ON A2-LAYER PCB.................................................. 38
FIGURE 27: COPLANAR WAVEGUIDE LINE DESIGN ON A4-LAYER PCB (LAYER 3 AS REFERENCE
GROUND).................................................................................................................................................. 38
FIGURE 28: COPLANAR WAVEGUIDE LINE DESIGN ON A4-LAYER PCB (LAYER 4 AS REFERENCE
GROUND).................................................................................................................................................. 38
FIGURE 29: DIMENSIONS OF THE U.FL-R-SMT CONNECTOR (UNIT: MM)................................................ 42
FIGURE 30: MECHANICALS OF U.FL-LP CONNECTORS............................................................................. 42
FIGURE 31: SPACE FACTOR OF MATED CONNECTOR (UNIT: MM)........................................................... 43
FIGURE 32: TOP VIEW OF THE MODULE...................................................................................................... 51
FIGURE 33: BOTTOM VIEW OF THE MODULE.............................................................................................. 51
FIGURE 34: TAPE DIMENSIONS (UNIT: MM).................................................................................................. 55
FIGURE 35: REEL DIMENSIONS (UNIT: MM) ................................................................................................. 55

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1Introduction
This document defines the BC66-NA module and describes its air interface and hardware interface which
are connected with the customers’ applications.
This document helps customers quickly understand the interface specifications, electrical and mechanical
details, as well as other related information of the module. To facilitate application designs, it also includes
some reference designs for customers’ reference. The document, coupled with application notes and user
guides, makes it easy to design and set up mobile applications with BC66-NA.

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1.1. 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 BC66-NA module. Manufacturers of the cellular
terminal should notify users and operating personnel of the following safety information by incorporating
these guidelines into all manuals supplied with the product. If not so, Quectel assumes no liability for any
user’s failure to observe 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 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 mobile phone or other cellular terminals. Areas with
potentially explosive atmospheres include fuelling 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.

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2Product Concept
2.1. General Description
BC66-NA 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 3GPP Rel.14). BC66-NA supports a broad range of frequency bands as listed below.
Table 1: Frequency Bands of BC66-NA Module
BC66-NA is an SMD type module with LCC and LGA package, and has an ultra-compact profile of
17.7mm ×15.8mm ×2.0mm. These make it can be easily embedded into size-constrained applications
and provide reliable connectivity with the applications.
BC66-NA provides abundant external interfaces (USB, UART, ADC, NETLIGHT, etc.) and protocol stacks
(UDP/TCP, LwM2M, MQTT, etc.), which provide great convenience for customers' applications.
Due to compact form factor, ultra-low power consumption and extended temperature range, BC66-NA is
a best choice for a wide range of IoT applications, such as smart metering, bike sharing, smart wearables,
smart parking, smart city, home appliances, security and asset tracking, agricultural and environmental
monitoring, etc. It is able to provide a complete range of SMS* and data transmission services to meet
customers’ demands.
The module fully complies with the RoHS directive of the European Union.
“*” means under development.
Mode
BC66-NA
H-FDD
B1/B2/B3/B4/B5/B8/B12/B13/B17/B18/B19/B20/B25/B26*/B28/B66/B71/B85
NOTE

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2.2. Key Features
The following table describes the detailed features of BC66-NA module.
Table 2: BC66-NA Key Features
Feature
Details
Power Supply
Supply voltage: 2.1V ~ 3.63V
Typical supply voltage: 3.3V
Power Saving
Typical power consumption: 3.5μA
Frequency Bands
LTE Cat NB2:
B1/B2/B3/B4/B5/B8/B12/B13/B17/B18/B19/B20/B25/B26*/B28/B66/B71/B85
Transmitting Power
23dBm±2dB
USIM Interface
Support 1.8V USIM card
USB Interface
Conform to USB 1.1 specifications, with maximum data transfer rate up to
12Mbps
Used for software debugging and upgrading
Support USB serial driver under Windows/Linux operating systems
UART Interfaces
Main UART Port:
Used forAT command communication and data transmission.
By default, the module is in auto-baud mode, and it supports automatic
baud rates not exceeding 115200bps. When powering on the module, the
MCU has to send AT command consecutively to synchronize baud rate
with the module. When OK is returned, it indicates the baud rate has been
synchronized successfully. When the module is woken up from Deep
Sleep mode, the baud rate synchronized during start-up will be used
directly.
Also can be used for firmware upgrade, and in such case, the baud rate is
921600bps by default.
Debug UART Port:
Used for firmware debugging
Default baud rate: 115200bps
Auxiliary UART Port:
Used for firmware debugging
Default baud rate: 115200bps
Network Protocols
UDP/TCP/LwM2M/MQTT/DTLS/TLS/SNTP/PPP*/CoAP*/ HTTP*/HTTPS*
SMS*
Text/PDU Mode

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1. 1) Within operation temperature range, the module is 3GPP compliant.
2. 2) Within extended temperature range, the module remains the ability to establish and maintain
functions such as SMS*, data transmission, etc., 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 operation
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 BC66-NA and illustrates the major functional parts.
Radio frequency
Baseband
Power management
Peripheral interfaces
Data Transmission
Features
Single-tone: Max. 103kbps (DL)/18kbps (UL)
Multi-tone: Max. 103kbps (DL )/151kbps (UL)
AT Commands
3GPP TS 27.005/3GPP TS 27.007 AT commands (3GPP Rel. 13/Rel.14)
and Quectel Enhanced AT commands
Firmware Update
Upgrade firmware via USB, main UART port or DFOTA
Real Time Clock
Supported
Physical
Characteristics
Size: (17.7±0.15)mm ×(15.8±0.15)mm ×(2.0±0.2)mm
Weight: 1.2g±0.2g
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
Antenna Interface
50Ωimpedance control
RoHS
All hardware components are fully compliant with EU RoHS directive
NOTES

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RF_ANT
FEM
PMU
BUCK
RF Transceiver
and Subsystem
XO
26MHz
XTAL
Baseband
RESET ADC
MAIN_UART
AUX_URAT
Flash
PSRAM
NETLIGHT
TX RX
32KHz
RTC BLOCK
LDO
PSM_ENIT
USIM
PWRKEY
DBG_UART
USIM
USB
VBAT
VDD_EXT
Figure 1: Functional Diagram
2.4. Development Board
Quectel provides a complete set of development tools to facilitate the use and testing of BC66-NA module.
The development tool kit includes the TE-B board, USB cable, antenna and other peripherals. For more
details, please refer to document [1].

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3Application Interfaces
3.1. General Description
BC66-NA is equipped with a total of 58 pins, including 44 LCC pins and 14 LGA pins. The subsequent
chapters will provide detailed descriptions of the following functions/pins/interfaces:
Power Supply
PWRKEY
RESET
USB Interface
UART Interfaces
USIM Interface
ADC Interface
RI Behaviors
Network Status Indication

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3.2. 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
SIM_GND
SIM_DATA
GND
RESERVED
RESERVED
RESERVED
RESERVED
TXD_AUX
RXD_AUX
GND
RESERVED
RESERVED
VDD_EXT
RESERVED
RESERVED
RI
PSM_EINT
RXD
TXD
NETLIGHT
RESET
SIM_VDD
VBAT_RF
POWER GND UART USIM ANT RESERVED
45
46
47
4849 50 5152
53
54
55
56
57
58
VBAT_BB GND
14
RF_ANT
GND GND GND RESERVED TXD_DBG RXD_DBG
SIM_RST
SIM_CLK
RESERVED
PWRKEY
RESERVED
GND
USB
BC66-NA
Top View
RESERVED
RESERVED
RESERVED
RESERVED
OTHERS
USB_MODE
VUSB_3V3
USB_DP
USB_DM
Figure 2: Pin Assignment
Keep all reserved pins unconnected.
NOTE

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3.3. Pin Description
Table 3: I/O Parameters Definition
Type
Description
AI
Analog input
AO
Analog output
DI
Digital input
DO
Digital output
IO
Bidirectional
PI
Power input
PO
Power output
Table 4: Pin Description
Power Supply
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
VBAT_BB
42
PI
Power supply for
the module’s
baseband part
Vmax=3.63V
Vmin=2.1V
Vnorm=3.3V
VBAT_RF
43
PI
Power supply for
the module’s RF
part
Vmax=3.63V
Vmin=2.1V
Vnorm=3.3V
VDD_
EXT
24
PO
1.8V output
power supply
Vnorm=1.8V
No voltage output in
Deep Sleep mode.
It is intended to supply
power for the module’s
pull-up circuits, and is
thus not recommended
to be used as the
power supply for
external circuits.
GND
1, 27, 34,
36, 37, 40,
41
GND

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Power Key Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
PWRKEY
7
DI
Pull down
PWRKEY to turn
on the module
VILmax=0.3*VBAT
VIHmin=0.7*VBAT
Reset Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
RESET
15
DI
Reset the module
Active low.
PSM_EINT Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
PSM_EINT
19
DI
Dedicated
external interrupt
pin.
Used to wake up
the module from
Deep Sleep.
Network Status Indication
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
NETLIGHT
16
DO
Network status
indication
ADC Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
ADC0
9
AI
General purpose
analog to digital
converter
interface
Voltage range:
0V~1.4V
Main UART Port
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
RXD
18
DI
Receive data from
TXD of DTE
1.8V power domain.
TXD
17
DO
Transmit data to
RXD of DTE
Auxiliary UART Port

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Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
RXD_AUX
28
DI
Receive data
from TXD of DTE
1.8V power domain.
TXD_AUX
29
DO
Transmit data to
RXD of DTE
Debug UART Port
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
RXD_DBG
38
DI
Receive data
from TXD of DTE
1.8V power domain.
TXD_DBG
39
DO
Transmit data to
RXD of DTE
Ringing Signal
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
RI
20
DO
Ring indication
signal
1.8V power domain.
USIM Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
SIM_VDD
14
DO
USIM card
power supply
Vnorm=1.8V
SIM_RST
12
DO
USIM card reset
signal
VOLmax=0.15×SIM_VDD
VOHmin=0.85×SIM_VDD
SIM_DATA
11
IO
USIM card data
signal
VILmax=0.25×SIM_VDD
VIHmin=0.75×SIM_VDD
VOLmax=0.15×SIM_VDD
VOHmin=0.85×SIM_VDD
SIM_CLK
13
DO
USIM card clock
signal
VOLmax=0.15×SIM_VDD
VOHmin=0.85×SIM_VDD
SIM_GND
10
GND
Specified
ground for USIM
card
Antenna Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
RF_ANT
35
IO
RF antenna
interface
50Ω characteristic
impedance
USB Interface

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Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
USB_MODE
47
DI
Pull down the pin
to achieve USB
download
function
VUSB_3V3
49
PI
USB power
supply
Vnorm=3.3V
USB_DP
50
IO
USB differential
data (+)
Conform to USB 1.1
specifications.
Request 90 Ω
differential
impedance.
USB_DM
51
IO
USB differential
data (-)
Reserved Pins
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
RESERVED
2~6, 8,
21~23,
25, 26,
30~33,
44~46,
48,
52~58
Keep these pins
unconnected.
1. Keep all unused pins unconnected.
2. “*”means under development.
3.4. Operating Modes
The module mainly consists of AP and modem, and the tables below describe the operating modes of the
AP, modem and the entire module.
NOTES

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Table 5: AP Operating Modes
Table 6: Modem Operating Modes
Table 7: Module Operating Modes
3.4.1. Deep Sleep
Based on system performance, the module consumes an ultra-low current (typically 3.5μA current
consumption) in deep sleep mode. Deep sleep mode is designed to reduce power consumption of the
module and improve battery life. The following figure shows the power consumption of the module
(modem) in different modes.
Mode
Description
Normal
In normal mode, the AP handles tasks, such asAT command communication.
Idle
When all tasks are suspended, theAP will enter idle mode.
Mode
Description
Connected
The network is connected and the module supports data transmission. In such a case,
the modem can switch to PSM or DRX/eDRX mode.
DRX/eDRX
The modem is in idle mode, and downlink data can be received during PTW only. In
such a case, the modem can switch to PSM or connected mode.
PSM
In power saving mode, the modem is disconnected from the network and cannot
receive any downlink data. In such a case, the modem can switch to connected mode.
Mode
Description
Active
When theAP is in normal mode and the modem is connected mode, the module will be
active and supports all services and functions.
The current consumption is active mode is higher than sleep modes.
Light Sleep
When the AP is in idle mode and the modem is in DRX/eDRX mode, the module will
enter light sleep mode. In such a case, the AP tasks will be suspended and the modem
will be able to receive downlink data during PTW only.
In light sleep mode, the current consumption of module is reduced greatly.
Deep Sleep
When the AP is idle mode and the modem is in PSM, the module will enter deep sleep
mode in which the CPU is powered off and only the 32kHz RTC clock is working.
In deep sleep mode, the current consumption will be reduced to the minimum (typically
3.5μA).