Quectel EC21 Series Supplement

EC21 Hardware Design
LTE Module Series
Rev. EC21_Hardware_Design_V1.4
Date: 2017-03-01
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About the Document
History
Revision
Date
Author
Description
1.0
2016-04-15
Yeoman CHEN
Initial
1.1
2016-09-22
Yeoman CHEN/
Frank WANG/
Lyndon LIU
1. Updated frequency bands in Table 1.
2. Updated transmitting power, supported maximum
baud rate of main UART, supported internet
protocols, supported USB drivers of USB interface,
and temperature range in Table 2.
3. Updated timing of turning on module in Figure 12.
4. Updated timing of turning off module in Figure 13.
5. Updated timing of resetting module in Figure 16.
6. Updated main UART supports baud rate in Chapter
3.11.
7. Added notes for ADC interface in Chapter 3.13.
8. Updated GNSS Performance in Table 21.
9. Updated operating frequencies of module in Table
23.
10. Added current consumption in Chapter 6.4.
11. Updated RF output power in Chapter 6.5.
12. Added RF receiving sensitivity in Chapter 6.6.
1.2
2016-11-04
Lyndon LIU/
Michael ZHANG
1. Added SGMII and WLAN interfaces in Table 2.
2. Updated function diagram in Figure 1.
3. Updated pin assignment (Top View) in Figure 2.
4. Added description of SGMII and WLAN interfaces in
Table 4.
5. Added SGMII interface in Chapter 3.17.
6. Added WLAN interface in Chapter 3.18.
7. Added USB_BOOT interface in Chapter 3.19.
8. Added reference design of RF layout in Chapter
5.1.4.
9. Added current consumption of EC21-V in Chapter
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6.4.
10. Added note about SIMO in Chapter 6.6.
1.3
2017-01-24
Lyndon LIU/
Rex WANG
1. Updated frequency bands in Table 1.
2. Updated function diagram in Figure 1.
3. Updated pin assignment (top view) in Figure 2.
4. Added BT interface in Chapter 3.18.2.
5. Updated reference circuit of wireless connectivity
interfaces with FC20 module in Figure 29.
6. Updated GNSS performance in Table 24.
7. Updated module operating frequencies in Table 26.
8. Added EC21-AUV current consumption in Table 38.
9. Updated EC21-A conducted RF receiving sensitivity
of in Table 42.
10. Added EC21-J conducted RF receiving sensitivity in
Table 48.
1.4
2017-03-01
Geely YANG
Deleted the LTE band TDD B41 of EC21-CT
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Contents
About the Document................................................................................................................................ 2
Contents.................................................................................................................................................... 4
Table Index ............................................................................................................................................... 6
Figure Index.............................................................................................................................................. 8
1Introduction..................................................................................................................................... 10
1.1. Safety Information..................................................................................................................11
2Product Concept ............................................................................................................................. 12
2.1. General Description ..............................................................................................................12
2.2. Key Features......................................................................................................................... 13
2.3. Functional Diagram............................................................................................................... 16
2.4. Evaluation Board...................................................................................................................16
3Application Interfaces..................................................................................................................... 17
3.1. General Description ..............................................................................................................17
3.2. Pin Assignment .....................................................................................................................18
3.3. Pin Description......................................................................................................................19
3.4. Operating Modes ..................................................................................................................28
3.5. Power Saving........................................................................................................................28
3.5.1. Sleep Mode..................................................................................................................28
3.5.1.1. UARTApplication............................................................................................... 28
3.5.1.2. USB Application with USB Remote Wakeup Function.......................................29
3.5.1.3. USB Application with USB Suspend/Resume and RI Function.......................... 30
3.5.1.4. USB Application without USB Suspend Function...............................................31
3.5.2. Airplane Mode.............................................................................................................. 32
3.6. Power Supply........................................................................................................................32
3.6.1. Power Supply Pins.......................................................................................................32
3.6.2. Decrease Voltage Drop................................................................................................33
3.6.3. Reference Design for Power Supply............................................................................34
3.6.4. Monitor the Power Supply............................................................................................35
3.7. Turn on and off Scenarios.....................................................................................................35
3.7.1. Turn on Module Using the PWRKEY...........................................................................35
3.7.2. Turn off Module............................................................................................................ 37
3.7.2.1. Turn off Module Using the PWRKEY Pin...........................................................37
3.7.2.2. Turn off Module UsingAT Command................................................................. 37
3.8. Reset the Module.................................................................................................................. 38
3.9. USIM Card Interface .............................................................................................................39
3.10. USB Interface........................................................................................................................ 41
3.11. UART Interfaces....................................................................................................................43
3.12. PCM and I2C Interfaces........................................................................................................ 45
3.13. ADC Function........................................................................................................................ 48
3.14. Network Status Indication .....................................................................................................49
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3.15. STATUS ................................................................................................................................ 50
3.16. Behavior of the RI .................................................................................................................51
3.17. SGMII Interface.....................................................................................................................51
3.18. Wireless Connectivity Interfaces...........................................................................................54
3.18.1. WLAN Interface ...........................................................................................................56
3.18.2. BT Interface*................................................................................................................56
3.19. USB_BOOT Interface............................................................................................................57
4GNSS Receiver................................................................................................................................ 58
4.1. General Description ..............................................................................................................58
4.2. GNSS Performance ..............................................................................................................58
4.3. Layout Guidelines .................................................................................................................59
5Antenna Interfaces.......................................................................................................................... 60
5.1. Main/Rx-diversity Antenna Interface .....................................................................................60
5.1.1. Pin Definition................................................................................................................ 60
5.1.2. Operating Frequency...................................................................................................60
5.1.3. Reference Design of RF Antenna Interface ................................................................. 61
5.1.4. Reference Design of RF Layout................................................................................... 62
5.2. GNSS Antenna Interface....................................................................................................... 64
5.3. Antenna Installation .............................................................................................................. 65
5.3.1. Antenna Requirement..................................................................................................65
5.3.2. Recommended RF Connector for Antenna Installation................................................ 66
6Electrical, Reliability and Radio Characteristics .......................................................................... 68
6.1. Absolute Maximum Ratings ..................................................................................................68
6.2. Power Supply Ratings........................................................................................................... 68
6.3. Operating Temperature.........................................................................................................69
6.4. Current Consumption............................................................................................................ 70
6.5. RF Output Power ..................................................................................................................76
6.6. RF Receiving Sensitivity .......................................................................................................76
6.7. Electrostatic Discharge .........................................................................................................80
7Mechanical Dimensions.................................................................................................................. 81
7.1. Mechanical Dimensions of the Module..................................................................................81
7.2. Recommended Footprint....................................................................................................... 83
7.3. Design Effect Drawings of the Module..................................................................................84
8Storage, Manufacturing and Packaging........................................................................................ 85
8.1. Storage .................................................................................................................................85
8.2. Manufacturing and Soldering................................................................................................ 86
8.3. Packaging.............................................................................................................................87
9Appendix A References.................................................................................................................. 88
10 Appendix B GPRS Coding Schemes............................................................................................. 92
11 Appendix C GPRS Multi-slot Classes............................................................................................ 93
12 Appendix D EDGE Modulation and Coding Schemes.................................................................. 94
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Table Index
TABLE 1: FREQUENCY BANDS OF EC21 SERIES MODULE........................................................................ 12
TABLE 2: EC21 KEY FEATURES OF EC21 MODULE..................................................................................... 13
TABLE 3: I/O PARAMETERS DEFINITION....................................................................................................... 19
TABLE 4: PIN DESCRIPTION........................................................................................................................... 19
TABLE 5: OVERVIEW OF OPERATING MODES............................................................................................. 28
TABLE 6: VBATAND GND PINS....................................................................................................................... 33
TABLE 7: PWRKEY PIN DESCRIPTION.......................................................................................................... 35
TABLE 8: RESET_N PIN DESCRIPTION......................................................................................................... 38
TABLE 9: PIN DEFINITION OF THE USIM CARD INTERFACE...................................................................... 39
TABLE 10: PIN DESCRIPTION OF USB INTERFACE..................................................................................... 41
TABLE 11: PIN DEFINITION OF THE MAIN UART INTERFACE..................................................................... 43
TABLE 12: PIN DEFINITION OF THE DEBUG UART INTERFACE................................................................. 43
TABLE 13: LOGIC LEVELS OF DIGITAL I/O.................................................................................................... 44
TABLE 14: PIN DEFINITION OF PCM AND I2C INTERFACES....................................................................... 46
TABLE 15: PIN DEFINITION OF THE ADC ...................................................................................................... 48
TABLE 16: CHARACTERISTIC OF THE ADC .................................................................................................. 48
TABLE 17: PIN DEFINITION OF NETWORK CONNECTION STATUS/ACTIVITY INDICATOR...................... 49
TABLE 18: WORKING STATE OF NETWORK CONNECTION STATUS/ACTIVITY INDICATOR................... 49
TABLE 19: PIN DEFINITION OF STATUS ........................................................................................................ 50
TABLE 20: BEHAVIOR OF THE RI ................................................................................................................... 51
TABLE 21: PIN DEFINITION OF THE SGMII INTERFACE.............................................................................. 52
TABLE 22: PIN DEFINITION OF WIRELESS CONNECTIVITY INTERFACES................................................ 54
TABLE 23: PIN DEFINITION OF USB_BOOT INTERFACE............................................................................. 57
TABLE 24: GNSS PERFORMANCE................................................................................................................. 58
TABLE 25: PIN DEFINITION OF THE RFANTENNA....................................................................................... 60
TABLE 26: MODULE OPERATING FREQUENCIES........................................................................................ 60
TABLE 27: PIN DEFINITION OF GNSSANTENNA INTERFACE..................................................................... 64
TABLE 28: GNSS FREQUENCY....................................................................................................................... 64
TABLE 29: ANTENNA REQUIREMENTS.......................................................................................................... 65
TABLE 30:ABSOLUTE MAXIMUM RATINGS.................................................................................................. 68
TABLE 31: POWER SUPPLY RATINGS........................................................................................................... 68
TABLE 32: OPERATING TEMPERATURE........................................................................................................ 69
TABLE 33: EC21-A CURRENT CONSUMPTION ............................................................................................. 70
TABLE 34: EC21-AUT CURRENT CONSUMPTION ........................................................................................ 71
TABLE 35: EC21-E CURRENT CONSUMPTION............................................................................................. 72
TABLE 36: EC21-KL CURRENT CONSUMPTION ........................................................................................... 73
TABLE 37: EC21-V CURRENT CONSUMPTION............................................................................................. 74
TABLE 38: EC21-AUV CURRENT CONSUMPTION........................................................................................ 74
TABLE 39: GNSS CURRENT CONSUMPTION OF EC21 SERIES MODULE................................................. 75
TABLE 40: RF OUTPUT POWER ..................................................................................................................... 76
TABLE 41: EC21-E CONDUCTED RF RECEIVING SENSITIVITY.................................................................. 76
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TABLE 42: EC21-ACONDUCTED RF RECEIVING SENSITIVITY.................................................................. 77
TABLE 43: EC21-V CONDUCTED RF RECEIVING SENSITIVITY.................................................................. 77
TABLE 44: EC21-AUT CONDUCTED RF RECEIVING SENSITIVITY............................................................. 77
TABLE 45: EC21-AUTL CONDUCTED RF RECEIVING SENSITIVITY........................................................... 78
TABLE 46: EC21-KL CONDUCTED RF RECEIVING SENSITIVITY................................................................ 78
TABLE 47: EC21-CT CONDUCTED RF RECEIVING SENSITIVITY................................................................ 78
TABLE 48: EC21-J CONDUCTED RF RECEIVING SENSITIVITY................................................................... 79
TABLE 49: EC21-AUV CONDUCTED RF RECEIVING SENSITIVITY............................................................. 79
TABLE 50: ELECTROSTATIC DISCHARGE CHARACTERISTICS ................................................................. 80
TABLE 51: RELATED DOCUMENTS................................................................................................................ 88
TABLE 52: TERMS AND ABBREVIATIONS...................................................................................................... 88
TABLE 53: DESCRIPTION OF DIFFERENT CODING SCHEMES.................................................................. 92
TABLE 54: GPRS MULTI-SLOT CLASSES ...................................................................................................... 93
TABLE 55: EDGE MODULATION AND CODING SCHEMES........................................................................... 94
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Figure Index
FIGURE 1: FUNCTIONAL DIAGRAM............................................................................................................... 16
FIGURE 2: PIN ASSIGNMENT (TOP VIEW) .................................................................................................... 18
FIGURE 3: SLEEP MODE APPLICATION VIA UART....................................................................................... 29
FIGURE 4: SLEEP MODE APPLICATION WITH USB REMOTE WAKEUP .................................................... 30
FIGURE 5: SLEEP MODE APPLICATION WITH RI......................................................................................... 31
FIGURE 6: SLEEP MODE APPLICATION WITHOUT SUSPEND FUNCTION................................................ 31
FIGURE 7: POWER SUPPLY LIMITS DURING BURST TRANSMISSION...................................................... 33
FIGURE 8: STAR STRUCTURE OF THE POWER SUPPLY............................................................................ 34
FIGURE 9: REFERENCE CIRCUIT OF POWER SUPPLY .............................................................................. 34
FIGURE 10: TURN ON THE MODULE USING DRIVING CIRCUIT................................................................. 35
FIGURE 11: TURN ON THE MODULE USING KEYSTROKE.......................................................................... 36
FIGURE 12: TIMING OF TURNING ON MODULE........................................................................................... 36
FIGURE 13: TIMING OF TURNING OFF MODULE......................................................................................... 37
FIGURE 14: REFERENCE CIRCUIT OF RESET_N BY USING DRIVING CIRCUIT ...................................... 38
FIGURE 15: REFERENCE CIRCUIT OF RESET_N BY USING BUTTON ...................................................... 38
FIGURE 16: TIMING OF RESETTING MODULE............................................................................................. 39
FIGURE 17: REFERENCE CIRCUIT OF USIM CARD INTERFACE WITH AN 8-PIN USIM CARD
CONNECTOR.................................................................................................................................................... 40
FIGURE 18: REFERENCE CIRCUIT OF USIM CARD INTERFACE WITH A 6-PIN USIM CARD CONNECTOR
........................................................................................................................................................................... 40
FIGURE 19: REFERENCE CIRCUIT OF USB APPLICATION......................................................................... 42
FIGURE 20: REFERENCE CIRCUIT WITH TRANSLATOR CHIP................................................................... 44
FIGURE 21: REFERENCE CIRCUIT WITH TRANSISTOR CIRCUIT.............................................................. 45
FIGURE 22: PRIMARY MODE TIMING............................................................................................................ 46
FIGURE 23: AUXILIARY MODE TIMING.......................................................................................................... 46
FIGURE 24: REFERENCE CIRCUIT OF PCM APPLICATION WITHAUDIO CODEC.................................... 47
FIGURE 25: REFERENCE CIRCUIT OF THE NETWORK INDICATOR.......................................................... 50
FIGURE 26: REFERENCE CIRCUITS OF STATUS......................................................................................... 50
FIGURE 27: SIMPLIFIED BLOCK DIAGRAM FOR ETHERNETAPPLICATION............................................. 52
FIGURE 28: REFERENCE CIRCUIT OF SGMII INTERFACE WITH PHYAR8033 APPLICATION................. 53
FIGURE 29: REFERENCE CIRCUIT OF WIRELESS CONNECTIVITY INTERFACES WITH FC20 MODULE
........................................................................................................................................................................... 55
FIGURE 30: REFERENCE CIRCUIT OF USB_BOOT INTERFACE................................................................ 57
FIGURE 31: REFERENCE CIRCUIT OF RF ANTENNA INTERFACE............................................................. 61
FIGURE 32: MICROSTRIP LINE DESIGN ON A 2-LAYER PCB...................................................................... 62
FIGURE 33: COPLANAR WAVEGUIDE LINE DESIGN ONA 2-LAYER PCB.................................................. 62
FIGURE 34: COPLANAR WAVEGUIDE LINE DESIGN ONA 4-LAYER PCB (LAYER 3 AS REFERENCE
GROUND).......................................................................................................................................................... 63
FIGURE 35: COPLANAR WAVEGUIDE LINE DESIGN ONA 4-LAYER PCB (LAYER 4 AS REFERENCE
GROUND).......................................................................................................................................................... 63
FIGURE 36: REFERENCE CIRCUIT OF GNSS ANTENNA............................................................................. 64
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FIGURE 37: DIMENSIONS OF THE UF.L-R-SMT CONNECTOR (UNIT: MM)................................................ 66
FIGURE 38: MECHANICALS OF UF.L-LP CONNECTORS............................................................................. 66
FIGURE 39: SPACE FACTOR OF MATED CONNECTOR (UNIT: MM)........................................................... 67
FIGURE 40: MODULE TOPAND SIDE DIMENSIONS..................................................................................... 81
FIGURE 41: MODULE BOTTOM DIMENSIONS (BOTTOM VIEW)................................................................. 82
FIGURE 42: RECOMMENDED FOOTPRINT (TOP VIEW).............................................................................. 83
FIGURE 43: TOP VIEW OF THE MODULE...................................................................................................... 84
FIGURE 44: BOTTOM VIEW OF THE MODULE.............................................................................................. 84
FIGURE 45: REFLOW SOLDERING THERMAL PROFILE.............................................................................. 86
FIGURE 46: TAPE AND REEL SPECIFICATIONS ........................................................................................... 87
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1Introduction
This document defines the EC21 module and describes its air interface and hardware interface which are
connected with your application.
This document can help you quickly understand module interface specifications, electrical and
mechanical details, as well as other related information of EC21 module. Associated with application note
and user guide, you can use EC21 module to design and set up mobile applications easily.
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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 EC21 module. 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 the
customer’s 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. You must comply with laws and regulations
restricting the use of wireless devices while driving.
Switch off the cellular terminal or mobile before boarding an aircraft. Make sure it is
switched off. The operation of wireless appliances in an aircraft is forbidden, so as
to prevent interference with communication systems. Consult the airline staff about
the use of wireless devices on boarding the aircraft, if your device offers an
Airplane Mode which must be enabled prior to boarding an aircraft.
Switch off your wireless device when in hospitals, clinics or other health care
facilities. These requests are designed to prevent possible interference with
sensitive medical equipment.
Cellular terminals or mobiles operating over radio frequency signal and cellular
network cannot be guaranteed to connect in all conditions, for example no mobile
fee or with an invalid USIM/SIM card. While you are in this condition and need
emergent help, please remember using emergency call. In order to make or
receive a call, the cellular terminal or mobile must be switched on and in a service
area with adequate cellular signal strength.
Your cellular terminal or mobile contains a transmitter and receiver. When it is ON,
it receives and transmits radio frequency energy. 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 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
EC21 is a series of LTE-FDD/LTE-TDD/WCDMA/GSM wireless communication module with receive
diversity. It provides data connectivity on LTE-FDD, LTE-TDD, DC-HSPA+, HSPA+, HSDPA, HSUPA,
WCDMA, EDGE and GPRS networks. It also provides GNSS1) and voice functionality2) for your specific
applications. EC21 contains ten variants: EC21-E, EC21-A, EC21-V, EC21-AUT, EC21-AU, EC21-AUV,
EC21-AUTL, EC21-J, EC21-CT and EC21-KL. You can choose a dedicated type based on the region or
operator. The following table shows the frequency bands of EC21 series module.
Table 1: Frequency Bands of EC21 Series Module
Modules2)
LTE Bands
3G Bands
GSM
Rx-
diversity
GNSS1)
EC21-E
FDD: B1/B3/B5/B7/B8/B20
WCDMA:
B1/B5/B8
900/1800
Y
GPS,
GLONASS,
BeiDou/
Compass,
Galileo,
QZSS
EC21-A
FDD: B2/B4/B12
WCDMA:
B2/B4/B5
N
Y
EC21-V
FDD: B4/B13
N
N
Y
EC21-AUT
FDD: B1/B3/B5/B7/B28
WCDMA:
B1/B5
N
Y
EC21-AU3)
FDD: B1/B2/B3/B4/B5/B7/B8/
B28
TDD: B40
WCDMA:
B1/B2/B5/B8
850/900/
1800/1900
Y
EC21-AUV
FDD: B1/B3/B5/B8/B28
B1/B5/B8
N
Y
N
EC21-AUTL
FDD: B3/B7/B28
N
N
Y
N
EC21-J
FDD: B1/B3/B8/B18/B19/B26
N
N
Y
N
EC21-CT
FDD: B1/B3/B5
N
N
N
N
EC21-KL
FDD: B1/B3/B5/B7/B8
N
N
Y
N
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1. 1) GNSS function is optional.
2. 2) EC21 series module (EC21-E, EC21-A, EC21-V, EC21-AUT, EC21-AU, EC21-AUV, EC21-AUTL,
EC21-J, EC21-CT and EC21-KL) includes Data-only and Telematics versions. Data-only version
does not support voice function, while Telematics version supports it.
3. 3) B2 band on EC21-AU module does not support Rx-diversity.
4. Y = supported (including LTE and WCDMA). N = Not supported.
With a compact profile of 32.0mm ×29.0mm ×2.4mm, EC21 can meet almost all requirements for M2M
applications such as automotive, metering, tracking system, security, router, wireless POS, mobile
computing device, PDA phone, tablet PC, etc.
EC21 is an SMD type module which can be embedded into applications through its 144-pin pads,
including 80 LCC signal pads and 64 other pads.
2.2. Key Features
The following table describes the detailed features of EC21 module.
Table 2: EC21 Key Features of EC21 Module
Features
Details
Power Supply
Supply voltage: 3.3V~4.3V Typical supply voltage: 3.8V
Transmitting Power
Class 4 (33dBm±2dB) for GSM850
Class 4 (33dBm±2dB) for GSM900
Class 1 (30dBm±2dB) for DCS1800
Class 1 (30dBm±2dB) for PCS1900
Class E2 (27dBm±3dB) for GSM850 8-PSK
Class E2 (27dBm±3dB) for GSM900 8-PSK
Class E2 (26dBm±3dB) for DCS1800 8-PSK
Class E2 (26dBm±3dB) for PCS1900 8-PSK
Class 3 (24dBm+1/-3dB) for WCDMA bands
Class 3 (23dBm±2dB) for LTE-FDD bands
Class 3 (23dBm±2dB) for LTE-TDD bands
LTE Features
Support up to non-CA CAT1
Support 1.4 to 20MHz RF bandwidth
Support MIMO in DL direction
FDD: Max 5Mbps (UL), 10Mbps (DL)
NOTES
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TDD: Max 3.1Mbps (UL), 8.96Mbps (DL)
WCDMA Features
Support 3GPP R8 DC-HSPA+
Support 16-QAM, 64-QAM and QPSK modulation
3GPP R6 CAT6 HSUPA: Max 5.76Mbps (UL)
3GPP R8 CAT24 DC-HSPA+: Max 42Mbps (DL)
GSM Features
R99:
CSD: 9.6kbps, 14.4kbps
GPRS:
Support GPRS multi-slot class 12 (12 by default)
Coding scheme: CS-1, CS-2, CS-3 and CS-4
Maximum of four Rx time slots per frame
EDGE:
Support EDGE multi-slot class 12 (12 by default)
Support GMSK and 8-PSK for different MCS (Modulation and Coding
Scheme)
Downlink coding schemes: CS 1-4 and MCS 1-9
Uplink coding schemes: CS 1-4 and MCS 1-9
Internet Protocol Features
Support TCP/UDP/PPP/FTP/HTTP/NTP/PING/QMI/HTTPS*/SMTP*/
MMS*/FTPS*/SSL* 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
USIM Interface
Support USIM/SIM card: 1.8V, 3.0V
Audio Features
Support one digital audio interface: PCM interface
GSM: HR/FR/EFR/AMR/AMR-WB
WCDMA: AMR/AMR-WB
LTE: AMR/AMR-WB
Support echo cancellation and noise suppression
PCM Interface
Used for audio function with external codec
Support 8-bit A-law*, μ-law* and 16-bit linear data formats
Support long frame synchronization and short frame synchronization
Support master and slave modes, but must be the master in long frame
synchronization
USB Interface
Compliant with USB 2.0 specification (slave only); the data transfer rate
can reach up to 480Mbps
Used for AT command communication, data transmission, GNSS NMEA
output, software debugging, firmware upgrade and voice over USB*
Support USB drivers for Windows XP, Windows Vista, Windows 7,
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Windows 8/8.1, Window 10, Linux 2.6 or later, Android
4.0/4.2/4.4/5.0/5.1/6.0
UART Interface
Main UART:
Used for AT command communication and data transmission
Baud rate reach up to 3000000bps, 115200bps by default
Support RTS and CTS hardware flow control
Debug UART:
Used for Linux console, log output
115200bps baud rate
SGMII Interface
Support 10/100/1000Mbps Ethernet connectivity
Wireless Connectivity
Interfaces
Support a low-power SDIO 3.0 interface for WLAN and UART/PCM
interface for Bluetooth*
Rx-diversity
Support LTE/WCDMA Rx-diversity
GNSS Features
Gen8C Lite of Qualcomm
Protocol: NMEA 0183
AT Commands
Compliant with 3GPP TS 27.007, 27.005 and Quectel enhanced AT
commands
Network Indication
Two pins including NET_MODE and NET_STATUS to indicate network
connectivity status
Antenna Interface
Including main antenna interface (ANT_MAIN), Rx-diversity antenna
interface (ANT_DIV) and GNSS antenna interface (ANT_GNSS)
Physical Characteristics
Size: (32.0±0.15) ×(29.0±0.15) ×(2.4±0.2)mm
Weight: approx. 4.9g
Temperature Range
Operation temperature range: -35°C ~ +75°C 1)
Extended temperature range: -40°C ~ +85°C 2)
Firmware Upgrade
USB interface and DFOTA*
RoHS
All hardware components are fully compliant with EU RoHS directive
1. 1) Within operating temperature range, the module is 3GPP compliant.
2. 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 normal operating temperature levels, the module will meet 3GPP specifications again.
3. “*” means under development.
NOTES
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2.3. Functional Diagram
The following figure shows a block diagram of EC21 and illustrates the major functional parts.
Power management
Baseband
DDR+NAND flash
Radio frequency
Peripheral interfaces
Baseband
PMIC
Transceiver NAND
DDR2
SDRAM
PA
Switch
LNA
Switch
ANT_MAIN ANT_DIVANT_GNSS
VBAT_BB
VBAT_RF
APT
PWRKEY
ADCs
VDD_EXT USB USIM PCM UART
I2C
RESET_N
19.2M
XO
STATUS
GPIOs
SAW
Control
IQ Control
Duplex
SAW
Tx
PRx DRx
SGMII WLAN BT
Figure 1: Functional Diagram
2.4. Evaluation Board
In order to help you develop applications with EC21, Quectel supplies an evaluation board (EVB), USB
data cable, earphone, antenna and other peripherals to control or test the module.
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3Application Interfaces
3.1. General Description
EC21 is equipped with 80-pin SMT pads plus 64-pin ground pads and reserved pads that can be
connected to cellular application platform. Sub-interfaces included in these pads are described in detail in
the following chapters:
Power supply
USIM interface
USB interface
UART interfaces
PCM interface
ADC interface
Status indication
SGMII interface
Wireless connectivity interfaces
USB_BOOT interface
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3.2. Pin Assignment
The following figure shows the pin assignment of EC21 module.
34
3
35 36 20 21 22 23 24 25 26 27 28 29 30 31 32 33
1
4
5
6
7
2
WAKEUP_IN1)
AP_READY
RESERVED
W_DISABLE#
NET_MODE1)
NET_STATUS
VDD_EXT
GND
GND
DBG_RXD
DBG_TXD
USIM_PRESENCE
USIM_VDD
USIM_DATA
USIM_CLK
USIM_RST
RESERVED
8
9
10
11
12
13
14
15
16
17
18
19
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
72 71 70 69 68 67 66 65 64 63 62 61 60 59 58 57 56 55
USIM_GND
GND
RESET_N
PWRKEY2)
GND
RESERVED
PCM_IN※ PCM_OUT※ PCM_SYNC※ PCM_CLK※
RESERVED RESERVED RESERVED RESERVED RESERVED RESERVED
ANT_DIV
GND
GND
USB_VBUS
USB_DM
USB_DP
RXD
TXD
DTR
RTS
CTS
DCD
RI
STATUS
VBAT_BB VBAT_BB
VBAT_RF
VBAT_RF
GND
RESERVED
GND
GND
ANT_MAIN
GND
ANT_GNSS
GND
ADC1
RESERVED
I2C_SDA
I2C_SCL
BT_CTS
ADC0
GND
GND
GND
73
74
75
76
77
78
79
80
81
82
83
84
100
101
102
106
107
111
112
103
104
109
105
110
89
94
98
88
93
97
86
91
96
85
90
95
99
87
92
108
113
RESERVED
RESERVED
117
126
125
124
123
122
121
120
119
118
127
128
115 USB_BOOT
RESERVED
116
139
140
138
137
136
135
134
133
132
131
130
129
114
RESERVED
Power Pins
BT_RXD
BT_TXD
BT_RTS
Signal Pins RESERVED PinsGND Pins
RESERVED
RESERVED
141
142
RESERVED
RESERVED
143
144
SGMII Pins
WLAN Pins Bluetooth Pins
Figure 2: Pin Assignment (Top View)
1. 1) means that these pins cannot be pulled up before startup.
2. 2) PWRKEY output voltage is 0.8V because of the diode drop in the Qualcomm chipset.
3. Pads 119~126 are SGMII function pins.
4. Pads 37~40, 118, 127 and 129~139 are wireless connectivity interfaces, among which pads 127 and
129~138 are WLAN function pins, and others are Bluetooth (BT) function pins. BT function is under
development.
5. Pads 24~27 are multiplexing pins used for audio design on EC21 module and BT function on FC20
NOTES
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module.
6. Keep all RESERVED pins and unused pins unconnected.
7. GND pads 85~112 should be connected to ground in the design, and RESERVED pads 73~84
should not be designed in schematic and PCB decal.
8. “※” means these interface functions are only supported on Telematics version.
3.3. Pin Description
The following tables show the pin definition of EC21 module.
Table 3: I/O Parameters Definition
Type
Description
IO
Bidirectional
DI
Digital input
DO
Digital output
PI
Power input
PO
Power output
AI
Analog input
AO
Analog output
OD
Open drain
Table 4: Pin Description
Power Supply
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
VBAT_BB
59, 60
PI
Power supply for
module baseband
part
Vmax=4.3V
Vmin=3.3V
Vnorm=3.8V
It must be able to provide
sufficient current up to
0.8A.
VBAT_RF
57, 58
PI
Power supply for
module RF part
Vmax=4.3V
Vmin=3.3V
Vnorm=3.8V
It must be able to provide
sufficient current up to
1.8A in a burst
transmission.
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