Quectel Wireless Solutions 201606EC21A Users Manual
EC21 Hardware Design
LTE Module Series
Rev. EC21_Hardware_Design_V1.5
Date: 2017-03-05
Status: Released
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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.
1.3
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
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Table 48.
1.4
2017-03-01
Geely YANG
Deleted the LTE band TDD B41 of EC21-CT
1.5
2018-03-05
Annice ZHANG/
Lyndon LIU/
Frank WANG
1. Updated functional diagram in Figure 1.
2. Updated frequency bands in Table 1.
3. Updated UMTS and GSM features in Table 2.
4. Updated description of pin 40/136/137/138.
5. Updated PWRKEY pulled down time to 500ms in
chapter 3.7.1 and reference circuit in Figure 10.
6. Updated reference circuit of (U)SIM interface in
Figure 17&18.
7. Updated reference circuit of USB interface in Figure
19.
8. Updated PCM mode in Chapter 3.12.
9. Updated USB_BOOT reference circuit in Chapter
3.20.
10. Added SD card interface in Chapter 3.13.
11. Updated module operating frequencies in Table 26.
12. Updated EC21 series modules current consumption
in Chapter 6.5.
13. Updated EC21 series modules conducted RF
receiving sensitivity in Chapter 6.6.
14. Added thermal consideration description in Chapter
6.8.
15. Updated dimension tolerance information in
Chapter 7.
16. Added storage temperature range in Table 2 and
Chapter 6.3.
17. Updated RF output power in Table 42.
18. Updated antenna requirements in Table 29.
19. Updated GPRS multi-slot classes in Table 55.
20. Updated storage information in Chapter 8.1
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Contents
About the Document.................................................................................................................................................2
Contents.......................................................................................................................................................................4
Table Index.................................................................................................................................................................. 7
Figure Index.................................................................................................................................................................9
1 Introduction...........................................................................................................................................................11
1.1. Safety Information......................................................................................................................................12
2 Product Concept..................................................................................................................................................13
2.1. General Description...................................................................................................................................13
2.2. Key Features.............................................................................................................................................. 14
2.3. Functional Diagram....................................................................................................................................17
2.4. Evaluation Board........................................................................................................................................17
3 Application Interfaces........................................................................................................................................ 18
3.1. General Description...................................................................................................................................18
.............................................................................................................................................. 错误！未定义书签。
3.2. Pin Description........................................................................................................................................... 19
3.3. Operating Modes........................................................................................................................................28
3.4. Power Saving..............................................................................................................................................29
3.4.1. Sleep Mode......................................................................................................................................29
3.4.1.1. UART Application................................................................................................................ 29
3.4.1.2. USB Application with USB Remote Wakeup Function................................................. 30
3.4.1.3. USB Application with USB Suspend/Resume and RI Function.................................. 31
3.4.1.4. USB Application without USB Suspend Function..........................................................31
3.4.2. Airplane Mode................................................................................................................................. 32
3.5. Power Supply..............................................................................................................................................33
3.5.1. Power Supply Pins......................................................................................................................... 33
3.5.2. Decrease Voltage Drop................................................................................................................. 33
3.5.3. Reference Design for Power Supply...........................................................................................34
3.5.4. Monitor the Power Supply.............................................................................................................35
3.6. Turn on and off Scenarios........................................................................................................................ 35
3.6.1. Turn on Module Using the PWRKEY.......................................................................................... 35
3.6.2. Turn off Module...............................................................................................................................37
3.6.2.1. Turn off Module Using the PWRKEY Pin........................................................................37
3.6.2.2. Turn off Module Using AT Command...............................................................................38
3.7. Reset the Module.......................................................................................................................................38
3.8. (U)SIM Interface.........................................................................................................................................40
3.9. USB Interface............................................................................................................................................. 42
3.10. UART Interfaces.......................................................................................................................................44
3.11. PCM and I2C Interfaces......................................................................................................................... 46
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3.12. SD Card Interface....................................................................................................................................48
3.13. ADC Interfaces.........................................................................................................................................51
3.14. Network Status Indication...................................................................................................................... 51
3.15. STATUS.....................................................................................................................................................53
3.16. Behaviors of RI.........................................................................................................................................53
3.17. SGMII Interface........................................................................................................................................54
4 GNSS Receiver.....................................................................................................................................................58
4.1. General Description...................................................................................................................................58
4.2. GNSS Performance...................................................................................................................................58
4.3. Layout Guidelines......................................................................................................................................59
5 Antenna Interfaces..............................................................................................................................................60
5.1. Main/Rx-diversity Antenna Interfaces.....................................................................................................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
6 Electrical, Reliability and Radio Characteristics........................................................................................ 68
6.1. Absolute Maximum Ratings..................................................................................................................... 68
6.2. Power Supply Ratings...............................................................................................................................69
6.3. Operation and Storage Temperatures....................................................................................................69
6.4. Current Consumption................................................................................................................................70
6.5. RF Output Power....................................................................................................................................... 76
6.6. RF Receiving Sensitivity...........................................................................................................................77
6.7. Electrostatic Discharge............................................................................................................................. 81
6.8. Thermal Consideration..............................................................................................................................81
7 Mechanical Dimensions.....................................................................................................................................84
7.1. Mechanical Dimensions of the Module.................................................................................................. 84
7.2. Recommended Footprint..........................................................................................................................86
7.3. Design Effect Drawings of the Module................................................................................................... 87
8 Storage, Manufacturing and Packaging........................................................................................................88
8.1. Storage........................................................................................................................................................ 88
8.2. Manufacturing and Soldering...................................................................................................................89
8.3. Packaging....................................................................................................................................................90
9 Appendix A References.....................................................................................................................................91
10 Appendix B GPRS Coding Schemes...........................................................................................................95
11 Appendix C GPRS Multi-slot Classes......................................................................................................... 96
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12 Appendix D EDGE Modulation and Coding Schemes............................................................................98
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Table Index
TABLE 1: FREQUENCY BANDS OF EC21 SERIES MODULE
................................................................................
13
TABLE 2: KEY FEATURES OF EC21 MODULE
..........................................................................................................
14
TABLE 3: I/O PARAMETERS DEFINITION
...................................................................................................................
19
TABLE 4: PIN DESCRIPTION
.........................................................................................................................................
19
TABLE 5: OVERVIEW OF OPERATING MODES
........................................................................................................
28
TABLE 6: VBAT AND GND PINS
....................................................................................................................................
33
TABLE 7: PIN DEFINITION OF PWRKEY
.....................................................................................................................
35
TABLE 8: PIN DEFINITION OF RESET_N
...................................................................................................................
38
TABLE 9: PIN DEFINITION OF THE (U)SIM INTERFACE
.........................................................................................
40
TABLE 10: PIN DESCRIPTION OF USB INTERFACE
...............................................................................................
42
TABLE 11: PIN DEFINITION OF MAIN UART INTERFACE
.......................................................................................
44
TABLE 12: PIN DEFINITION OF DEBUG UART INTERFACE
..................................................................................
44
TABLE 13: LOGIC LEVELS OF DIGITAL I/O
................................................................................................................
45
TABLE 14: PIN DEFINITION OF PCM AND I2C INTERFACES
................................................................................
47
TABLE 15: PIN DEFINITION OF SD CARD INTERFACE
..........................................................................................
49
TABLE 16: PIN DEFINITION OF ADC INTERFACES
.................................................................................................
51
TABLE 17: CHARACTERISTIC OF ADC
.......................................................................................................................
51
TABLE 18: PIN DEFINITION OF NETWORK CONNECTION STATUS/ACTIVITY INDICATOR
..........................
52
TABLE 19: WORKING STATE OF NETWORK CONNECTION STATUS/ACTIVITY INDICATOR
........................
52
TABLE 20: PIN DEFINITION OF STATUS
.....................................................................................................................
53
TABLE 21: BEHAVIOR OF RI
.........................................................................................................................................
54
TABLE 22: PIN DEFINITION OF THE SGMII INTERFACE
........................................................................................
54
TABLE 23: PIN DEFINITION OF WIRELESS CONNECTIVITY INTERFACES....................... 错误！未定义书签。
TABLE 24: PIN DEFINITION OF USB_BOOT INTERFACE
.......................................................................................
56
TABLE 25: GNSS PERFORMANCE
..............................................................................................................................
58
TABLE 26: PIN DEFINITION OF RF ANTENNAS
........................................................................................................
60
TABLE 27: MODULE OPERATING FREQUENCIES
..................................................................................................
60
TABLE 28: PIN DEFINITION OF GNSS ANTENNA INTERFACE
..............................................................................
64
TABLE 29: GNSS FREQUENCY
....................................................................................................................................
64
TABLE 30: ANTENNA REQUIREMENTS
.......................................................................................................................
65
TABLE 31: ABSOLUTE MAXIMUM RATINGS
..............................................................................................................
68
TABLE 32: POWER SUPPLY RATINGS
.......................................................................................................................
69
TABLE 33: OPERATION AND STORAGE TEMPERATURES
...................................................................................
69
TABLE 34: EC21-E CURRENT CONSUMPTION
........................................................................................................
70
TABLE 35: EC21-A CURRENT CONSUMPTION
........................................................................................................
72
TABLE 36: EC21-V CURRENT CONSUMPTION
........................................................................................................
73
TABLE 37: EC21-AUT CURRENT CONSUMPTION
...................................................................................................
73
TABLE 38: EC21-AUV CURRENT CONSUMPTION
...................................................................................................
74
TABLE 39: EC21-J CURRENT CONSUMPTION
.........................................................................................................
75
TABLE 40: EC21-KL CURRENT CONSUMPTION
......................................................................................................
76
TABLE 41: GNSS CURRENT CONSUMPTION OF EC21 SERIES MODULE
.......................................................
76
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TABLE 42: RF OUTPUT POWER................................................................................................................................... 77
TABLE 43: EC21-E CONDUCTED RF RECEIVING SENSITIVITY........................................................................... 77
TABLE 44: EC21-A CONDUCTED RF RECEIVING SENSITIVITY........................................................................... 78
TABLE 45: EC21-V CONDUCTED RF RECEIVING SENSITIVITY........................................................................... 78
TABLE 46: EC21-AUT CONDUCTED RF RECEIVING SENSITIVITY......................................................................78
TABLE 47: EC21-KL CONDUCTED RF RECEIVING SENSITIVITY......................................................................... 79
TABLE 48: EC21-J CONDUCTED RF RECEIVING SENSITIVITY............................................................................79
TABLE 49: EC21-AUV CONDUCTED RF RECEIVING SENSITIVITY..................................................................... 79
TABLE 50: EC21-AU CONDUCTED RF RECEIVING SENSITIVITY........................................................................ 80
TABLE 51: ELECTROSTATIC DISCHARGE CHARACTERISTICS.......................................................................... 81
TABLE 52: RELATED DOCUMENTS............................................................................................................................. 91
TABLE 53: TERMS AND ABBREVIATIONS.................................................................................................................. 91
TABLE 54: DESCRIPTION OF DIFFERENT CODING SCHEMES.......................................................................... 95
TABLE 55: GPRS MULTI-SLOT CLASSES.................................................................................................................. 96
TABLE 56: EDGE MODULATION AND CODING SCHEMES................................................................................... 98
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Figure Index
FIGURE 1: FUNCTIONAL DIAGRAM
............................................................................................................................
17
FIGURE 2: PIN ASSIGNMENT (TOP VIEW).................................................................................错误！未定义书签。
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
......................................................
32
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
........................................................................................
35
FIGURE 10: TURN ON THE MODULE BY USING DRIVING CIRCUIT
..................................................................
36
FIGURE 11: TURN ON THE MODULE BY USING BUTTON
.....................................................................................
36
FIGURE 12: TIMING OF TURNING ON MODULE
......................................................................................................
37
FIGURE 13: TIMING OF TURNING OFF MODULE
....................................................................................................
38
FIGURE 14: REFERENCE CIRCUIT OF RESET_N BY USING DRIVING CIRCUIT
............................................
39
FIGURE 15: REFERENCE CIRCUIT OF RESET_N BY USING BUTTON
.............................................................
39
FIGURE 16: TIMING OF RESETTING MODULE
........................................................................................................
40
FIGURE 17: REFERENCE CIRCUIT OF (U)SIM INTERFACE WITH AN 8-PIN (U)SIM CARD CONNECTOR
.....................................................................................................................................................................................
41
FIGURE 18: REFERENCE CIRCUIT OF (U)SIM INTERFACE WITH A 6-PIN (U)SIM CARD CONNECTOR..41
FIGURE 19: REFERENCE CIRCUIT OF USB APPLICATION
..................................................................................
43
FIGURE 20: REFERENCE CIRCUIT WITH TRANSLATOR CHIP
............................................................................
45
FIGURE 21: REFERENCE CIRCUIT WITH TRANSISTOR CIRCUIT
......................................................................
46
FIGURE 22: PRIMARY MODE TIMING
.........................................................................................................................
47
FIGURE 23: AUXILIARY MODE TIMING
......................................................................................................................
47
FIGURE 24: REFERENCE CIRCUIT OF PCM APPLICATION WITH AUDIO CODEC
.........................................
48
FIGURE 25: REFERENCE CIRCUIT OF SD CARD
...................................................................................................
50
FIGURE 26: REFERENCE CIRCUIT OF THE NETWORK INDICATOR
.................................................................
52
FIGURE 27: REFERENCE CIRCUITS OF STATUS
....................................................................................................
53
FIGURE 28: SIMPLIFIED BLOCK DIAGRAM FOR ETHERNET APPLICATION
...................................................
55
FIGURE 29: REFERENCE CIRCUIT OF SGMII INTERFACE WITH PHY AR8033 APPLICATION
...................
56
FIGURE 30: REFERENCE CIRCUIT OF WIRELESS CONNECTIVITY INTERFACES WITH FC20 MODULE 错
误！未定义书签。
FIGURE 31: REFERENCE CIRCUIT OF USB_BOOT INTERFACE
........................................................................
57
FIGURE 32: REFERENCE CIRCUIT OF RF ANTENNA INTERFACE
.....................................................................
62
FIGURE 33: MICROSTRIP LINE DESIGN ON A 2-LAYER PCB
..............................................................................
62
FIGURE 34: COPLANAR WAVEGUIDE LINE DESIGN ON A 2-LAYER PCB
........................................................
63
FIGURE 35: COPLANAR WAVEGUIDE LINE DESIGN ON A 4-LAYER PCB (LAYER 3 AS REFERENCE
GROUND)
..................................................................................................................................................................
63
FIGURE 36: COPLANAR WAVEGUIDE LINE DESIGN ON A 4-LAYER PCB (LAYER 4 AS REFERENCE
GROUND)
..................................................................................................................................................................
63
FIGURE 37: REFERENCE CIRCUIT OF GNSS ANTENNA
......................................................................................
65
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FIGURE 38: DIMENSIONS OF THE U.FL-R-SMT CONNECTOR (UNIT: MM)...................................................... 66
FIGURE 39: MECHANICALS OF U.FL-LP CONNECTORS...................................................................................... 67
FIGURE 40: SPACE FACTOR OF MATED CONNECTOR (UNIT: MM)................................................................... 67
FIGURE 41: REFERENCED HEATSINK DESIGN (HEATSINK AT THE TOP OF THE MODULE)..................... 82
FIGURE 42: REFERENCED HEATSINK DESIGN (HEATSINK AT THE BOTTOM OF CUSTOMERS’ PCB)...82
FIGURE 43: MODULE TOP AND SIDE DIMENSIONS...............................................................................................84
FIGURE 44: MODULE BOTTOM DIMENSIONS (BOTTOM VIEW).......................................................................... 85
FIGURE 45: RECOMMENDED FOOTPRINT (TOP VIEW)........................................................................................ 86
FIGURE 46: TOP VIEW OF THE MODULE.................................................................................................................. 87
FIGURE 47: BOTTOM VIEW OF THE MODULE......................................................................................................... 87
FIGURE 48: REFLOW SOLDERING THERMAL PROFILE....................................................................................... 89
FIGURE 49: TAPE AND REEL SPECIFICATIONS...................................................................................................... 90
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1 Introduction
This document defines the EC21 module and describes its air interface and hardware interface which are
connected with customers’ applications.
This document can help customers 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, customers 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
customers’ failure to comply with these precautions.
Full attention must be given to driving at all times in order to reduce the risk of an
accident. Using a mobile while driving (even with a handsfree kit) causes
distraction and can lead to an accident. 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 desinged 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 (U)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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2 Product 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-HSDPA, HSPA+, HSDPA, HSUPA,
WCDMA, EDGE and GPRS networks. It also provides GNSS1)and voice functionality2)for customers’
specific applications. EC21 contains nine variants: EC21-E, EC21-A, EC21-V, EC21-AU, EC21-AUT,
EC21-AUV, EC21-J, EC21-KL and EC20-CEL. Customers 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
Modules
2)
LTE Bands
UMTS Bands
GSM
Rx-
diversity
GNSS
1)
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
NNY
EC21-AU
3)
FDD: B1/B2/B3/B4/B5/B7/B8/
B28
TDD: B40
WCDMA:
B1/B2/B5/B8
850/900/
1800/1900
Y
EC21-AUT
FDD: B1/B3/B5/B7/B28
WCDMA:
B1/B5
N
Y
EC21-AUV
FDD: B1/B3/B5/B8/B28
B1/B5/B8
NYN
EC21-J
FDD: B1/B3/B8/B18/B19/B26
NNY
N
EC21-KL
FDD: B1/B3/B5/B7/B8
NNY
N
EC20-CEL
FDD: B1/B3/B5
NNN
N
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1.
1)
GNSS function is optional.
2.
2)
EC21 series module (EC21-E, EC21-A, EC21-V, EC21-AU, EC21-AUT, EC21-AUV, EC21-J,
EC21-KL and EC20-CEL) contains Telematics version and Data-only version. Telematics version
supports voice and data functions, while Data-only version only supports data function.
3.
3)
B2 band on EC21-AU module does not support Rx-diversity.
4. Y = Supported. N = Not supported.
With a compact profile of 29.0mm × 32.0mm × 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: 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 Cat 1 FDD and TDD
Support 1.4MHz~20MHz RF bandwidth
Support MIMO in DL direction
LTE-FDD: Max 10Mbps (DL)/5Mbps (UL)
NOTES
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LTE-TDD: Max 8.96Mbps (DL)/3.1Mbps (UL)
UMTS Features
Support 3GPP R8 DC-HSDPA, HSPA+, HSDPA, HSUPA and WCDMA
Support QPSK, 16-QAM and 64-QAM modulation
DC-HSDPA: Max 42Mbps (DL)
HSUPA: Max 5.76Mbps (UL)
WCDMA: Max 384Kbps (DL)/384Kbps (UL)
GSM Features
GPRS:
Support GPRS multi-slot class 33 (33 by default)
Coding scheme: CS-1, CS-2, CS-3 and CS-4
Max 107Kbps (DL)/85.6Kbps (UL)
EDGE:
Support EDGE multi-slot class 33 (33 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
Max 296Kbps (DL)/ 236.8Kbps (UL)
Internet Protocol Features
Support TCP/UDP/PPP/FTP/HTTP/NTP/PING/QMI/ CMUX*/HTTPS*/
SMTP*/ MMS*/FTPS*/SMTPS*/SSL*/FILE* protocols
Support PAP (Password Authentication Protocol) and CHAP (Challenge
Handshake Authentication Protocol) protocols which are usually used for
PPP connections
SMS
Text and PDU mode
Point to point MO and MT
SMS cell broadcast
SMS storage: ME by default
(U)SIM Interface
Support 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 serial drivers for: Windows XP, Windows Vista, Windows
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7/8/8.1/10, Windows CE 5.0/6.0/7.0*, Linux 2.6/3.x/4.1,
Android 4.x/5.x/6.x/7.x
UART Interface
Main UART:
Used for AT command communication and data transmission
Baud rates reach up to 921600bps, 115200bps by default
Support RTS and CTS hardware flow control
Debug UART:
Used for Linux console and log output
115200bps baud rate
SD Card Interface
Support SD 3.0 protocol
SGMII Interface
Support 10/100/1000Mbps Ethernet connectivity
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: (29.0±0.15)mm × (32.0±0.15)mm × (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)
Storage temperature range: -40°C ~ +90°C
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 P
out
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
Figure 1: Functional Diagram
2.4. Evaluation Board
In order to help customers develop applications with EC21, Quectel supplies an evaluation board (EVB),
USB to RS-232 converter cable, earphone, antenna and other peripherals to control or test the module.
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3 Application Interfaces
3.1. General Description
EC21 is equipped with 80 LCC pads plus 64 LGA 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
(U)SIM interface
USB interface
UART interfaces
PCM and I2C interfaces
SD card interface
ADC interfaces
Status indication
SGMII interface
Wireless connectivity interfaces
USB_BOOT interface
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3.2. 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’s 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’s 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.
VDD_EXT
7
PO
Provide 1.8V for
external circuit
Vnorm=1.8V
IOmax=50mA
Power supply for
external GPIO’s pull-up
circuits.
If unused, keep it open.
GND
8, 9, 19,
22, 36, 46,
Ground
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48, 50~54,
56, 72,
85~112
Turn on/off
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
PWRKEY
21
DI
Turn on/off the
module
VIHmax=2.1V
VIHmin=1.3V
VILmax=0.5V
The output voltage is
0.8V because of the
diode drop in the
Qualcomm chipset.
RESET_N
20
DI
Reset signal of the
module
VIHmax=2.1V
VIHmin=1.3V
VILmax=0.5V
If unused, keep it
open.
Status Indication
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
STATUS
61
OD
Indicate the module
operating status
The drive current
should be less than
0.9mA.
Require external
pull-up. If unused,
keep it open.
NET_MODE
5
DO
Indicate the module
network registration
mode
VOHmin=1.35V
VOLmax=0.45V
1.8V power domain.
It cannot be pulled up
before startup.
If unused, keep it
open.
NET_
STATUS
6
DO
Indicate the module
network activity
status
VOHmin=1.35V
VOLmax=0.45V
1.8V power domain.
If unused, keep it
open.
USB Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
USB_VBUS
71PIUSB detection
Vmax=5.25V
Vmin=3.0V
Vnorm=5.0V
Typical: 5.0V
If unused, keep it
open.
USB_DP
69
IO
USB differential data
bus (+)
Compliant with USB
2.0 standard
specification.
Require differential
impedance of 90Ω.
If unused, keep it
open.
USB_DM
70
IO
USB differential data
bus (-)
Compliant with USB
2.0 standard
specification.
Require differential
impedance of 90Ω.
If unused, keep it
open.
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(U)SIM Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
USIM_GND
10
Specified ground for
(U)SIM card
USIM_VDD
14
PO
Power supply for
(U)SIM card
For 1.8V (U)SIM:
Vmax=1.9V
Vmin=1.7V
For 3.0V (U)SIM:
Vmax=3.05V
Vmin=2.7V
IOmax=50mA
Either 1.8V or 3.0V is
supported by the
module automatically.
USIM_DATA
15
IO
Data signal of
(U)SIM card
For 1.8V (U)SIM:
VILmax=0.6V
VIHmin=1.2V
VOLmax=0.45V
VOHmin=1.35V
For 3.0V (U)SIM:
VILmax=1.0V
VIHmin=1.95V
VOLmax=0.45V
VOHmin=2.55V
USIM_CLK
16
DO
Clock signal of
(U)SIM card
For 1.8V (U)SIM:
VOLmax=0.45V
VOHmin=1.35V
For 3.0V (U)SIM:
VOLmax=0.45V
VOHmin=2.55V
USIM_RST
17
DO
Reset signal of
(U)SIM card
For 1.8V (U)SIM:
VOLmax=0.45V
VOHmin=1.35V
For 3.0V (U)SIM:
VOLmax=0.45V
VOHmin=2.55V
USIM_
PRESENCE
13
DI
(U)SIM card
insertion detection
VILmin=-0.3V
VILmax=0.6V
VIHmin=1.2V
VIHmax=2.0V
1.8V power domain.
If unused, keep it
open.
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Main UART Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
RI62DO
Ring indicator
VOLmax=0.45V
VOHmin=1.35V
1.8V power domain.
If unused, keep it
open.
DCD
63
DO
Data carrier
detection
VOLmax=0.45V
VOHmin=1.35V
1.8V power domain.
If unused, keep it
open.
CTS
64DOClear to send
VOLmax=0.45V
VOHmin=1.35V
1.8V power domain.
If unused, keep it
open.
RTS
65DIRequest to send
VILmin=-0.3V
VILmax=0.6V
VIHmin=1.2V
VIHmax=2.0V
1.8V power domain.
If unused, keep it
open.
DTR
66
DI
Data terminal ready,
sleep mode control
VILmin=-0.3V
VILmax=0.6V
VIHmin=1.2V
VIHmax=2.0V
1.8V power domain.
Pulled up by default.
Low level wakes up
the module.
If unused, keep it
open.
TXD
67DOTransmit data
VOLmax=0.45V
VOHmin=1.35V
1.8V power domain.
If unused, keep it
open.
RXD
68DIReceive data
VILmin=-0.3V
VILmax=0.6V
VIHmin=1.2V
VIHmax=2.0V
1.8V power domain.
If unused, keep it
open.
Debug UART Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
DBG_TXD
12DOTransmit data
VOLmax=0.45V
VOHmin=1.35V
1.8V power domain.
If unused, keep it
open.
DBG_RXD
11DIReceive data
VILmin=-0.3V
VILmax=0.6V
VIHmin=1.2V
VIHmax=2.0V
1.8V power domain.
If unused, keep it
open.
ADC Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
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ADC0
45
AI
General purpose
analog to digital
converter
Voltage range:
0.3V to VBAT_BB
If unused, keep it
open.
ADC1
44
AI
General purpose
analog to digital
converter
Voltage range:
0.3V to VBAT_BB
If unused, keep it
open.
PCM Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
PCM_IN
24DIPCM data input
VILmin=-0.3V
VILmax=0.6V
VIHmin=1.2V
VIHmax=2.0V
1.8V power domain.
If unused, keep it
open.
PCM_OUT
25DOPCM data output
VOLmax=0.45V
VOHmin=1.35V
1.8V power domain.
If unused, keep it
open.
PCM_SYNC
26
IO
PCM data frame
synchronization
signal
VOLmax=0.45V
VOHmin=1.35V
VILmin=-0.3V
VILmax=0.6V
VIHmin=1.2V
VIHmax=2.0V
1.8V power domain.
In master mode, it is
an output signal.
In slave mode, it is an
input signal.
If unused, keep it
open.
PCM_CLK
27IOPCM clock
VOLmax=0.45V
VOHmin=1.35V
VILmin=-0.3V
VILmax=0.6V
VIHmin=1.2V
VIHmax=2.0V
1.8V power domain.
In master mode, it is
an output signal.
In slave mode, it is an
input signal.
If unused, keep it
open.
I2C Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
I2C_SCL
41
OD
I2C serial clock.
Used for external
codec
External pull-up
resistor is required.
1.8V only.
If unused, keep it
open.
I2C_SDA
42
OD
I2C serial data.
Used for external
codec
External pull-up
resistor is required.
1.8V only.
If unused, keep it
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open.
SD Card Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
SDC2_
DATA3
28
IO
SD card SDIO bus
DATA3
1.8V signaling:
VOLmax=0.45V
VOHmin=1.4V
VILmin=-0.3V
VILmax=0.58V
VIHmin=1.27V
VIHmax=2.0V
3.0V signaling:
VOLmax=0.38V
VOHmin=2.01V
VILmin=-0.3V
VILmax=0.76V
VIHmin=1.72V
VIHmax=3.34V
SDIO signal level can
be selected according
to SD card supported
level, more details
please refer to SD 3.0
protocol.
If unused, keep it
open.
SDC2_
DATA2
29
IO
SD card SDIO bus
DATA2
1.8V signaling:
VOLmax=0.45V
VOHmin=1.4V
VILmin=-0.3V
VILmax=0.58V
VIHmin=1.27V
VIHmax=2.0V
3.0V signaling:
VOLmax=0.38V
VOHmin=2.01V
VILmin=-0.3V
VILmax=0.76V
VIHmin=1.72V
VIHmax=3.34V
SDIO signal level can
be selected according
to SD card supported
level, more details
please refer to SD 3.0
protocol.
If unused, keep it
open.
SDC2_
DATA1
30
IO
SD card SDIO bus
DATA1
1.8V signaling:
VOLmax=0.45V
VOHmin=1.4V
VILmin=-0.3V
VILmax=0.58V
VIHmin=1.27V
VIHmax=2.0V
3.0V signaling:
SDIO signal level can
be selected according
to SD card supported
level, more details
please refer to SD 3.0
protocol.
If unused, keep it
open.
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VOLmax=0.38V
VOHmin=2.01V
VILmin=-0.3V
VILmax=0.76V
VIHmin=1.72V
VIHmax=3.34V
SDC2_
DATA0
31
IO
SD card SDIO bus
DATA0
1.8V signaling:
VOLmax=0.45V
VOHmin=1.4V
VILmin=-0.3V
VILmax=0.58V
VIHmin=1.27V
VIHmax=2.0V
3.0V signaling:
VOLmax=0.38V
VOHmin=2.01V
VILmin=-0.3V
VILmax=0.76V
VIHmin=1.72V
VIHmax=3.34V
SDIO signal level can
be selected according
to SD card supported
level, more details
please refer to SD 3.0
protocol.
If unused, keep it
open.
SDC2_CLK
32
DO
SD card SDIO bus
clock
1.8V signaling:
VOLmax=0.45V
VOHmin=1.4V
3.0V signaling:
VOLmax=0.38V
VOHmin=2.01V
SDIO signal level can
be selected according
to SD card supported
level, more details
please refer to SD 3.0
protocol.
If unused, keep it
open.
SDC2_CMD
33
IO
SD card SDIO bus
command
1.8V signaling:
VOLmax=0.45V
VOHmin=1.4V
VILmin=-0.3V
VILmax=0.58V
VIHmin=1.27V
VIHmax=2.0V
3.0V signaling:
VOLmax=0.38V
VOHmin=2.01V
VILmin=-0.3V
VILmax=0.76V
VIHmin=1.72V
VIHmax=3.34V
SDIO signal level can
be selected according
to SD card supported
level, more details
please refer to SD 3.0
protocol.
If unused, keep it
open.
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SD_INS_
DET
23
DI
SD card insertion
detect
VILmin=-0.3V
VILmax=0.6V
VIHmin=1.2V
VIHmax=2.0V
1.8V power domain.
If unused, keep it
open.
VDD_SDIO
34
PO
SD card SDIO bus
pull-up power
IOmax=50mA
1.8V/2.85V
configurable. Cannot
be used for SD card
power.
If unused, keep it
open.
SGMII Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
EPHY_RST_N
119DOEthernet PHY reset
For 1.8V:
VOLmax=0.45V
VOHmin=1.4V
For 2.85V:
VOLmax=0.35V
VOHmin=2.14V
1.8V/2.85V power
domain.
If unused, keep it
open.
EPHY_INT_N
120
DI
Ethernet PHY
interrupt
VILmin=-0.3V
VILmax=0.6V
VIHmin=1.2V
VIHmax=2.0V
1.8V power domain.
If unused, keep it
open.
SGMII_
MDATA
121
IO
SGMII MDIO
(Management Data
Input/Output) data
For 1.8V:
VOLmax=0.45V
VOHmin=1.4V
VILmax=0.58V
VIHmin=1.27V
For 2.85V:
VOLmax=0.35V
VOHmin=2.14V
VILmax=0.71V
VIHmin=1.78V
1.8V/2.85V power
domain.
If unused, keep it
open.
SGMII_
MCLK
122
DO
SGMII MDIO
(Management Data
Input/Output) clock
For 1.8V:
VOLmax=0.45V
VOHmin=1.4V
For 2.85V:
VOLmax=0.35V
VOHmin=2.14V
1.8V/2.85V power
domain.
If unused, keep it
open.
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USIM2_VDD
128
PO
SGMII MDIO pull-up
power source
Configurable power
source.
1.8V/2.85V power
domain.
External pull-up for
SGMII MDIO pins.
If unused, keep it
open.
SGMII_TX_M
123
AO
SGMII transmission
- minus
If unused, keep it
open.
SGMII_TX_P
124
AO
SGMII transmission
- plus
If unused, keep it
open.
SGMII_RX_P
125
AI
SGMII receiving
- plus
If unused, keep it
open.
SGMII_RX_M
126
AI
SGMII receiving
- minus
If unused, keep it
open.
RF Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
ANT_DIV
35
AI
Diversity antenna
pad
50Ω impedance
If unused, keep it
open.
ANT_MAIN
49IOMain antenna pad
50Ω impedance
ANT_GNSS
47AIGNSS antenna pad
50Ω impedance
If unused, keep it
open.
GPIO Pins
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
WAKEUP_IN
1DISleep mode control
VILmin=-0.3V
VILmax=0.6V
VIHmin=1.2V
VIHmax=2.0V
1.8V power domain.
Cannot be pulled up
before startup.
Low level wakes up
the module.
If unused, keep it
open.
W_DISABLE#
4
DI
Airplane mode
control
VILmin=-0.3V
VILmax=0.6V
VIHmin=1.2V
VIHmax=2.0V
1.8V power domain.
Pull-up by default.
At low voltage level,
module can enter into
airplane mode.
If unused, keep it
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1. “*” means under development.
2. Pads 24~27 are multiplexing pins used for audio design on EC21 module and BT function on FC20
module.
3.3. Operating Modes
The table below briefly summarizes the various operating modes referred in the following chapters.
Table 5: Overview of Operating Modes
Mode
Details
Normal
Operation
Idle
Software is active. The module has registered on the network, and it is
ready to send and receive data.
Talk/Data
Network connection is ongoing. In this mode, the power consumption is
decided by network setting and data transfer rate.
open.
AP_READY
2
DI
Application
processor sleep
state detection
VILmin=-0.3V
VILmax=0.6V
VIHmin=1.2V
VIHmax=2.0V
1.8V power domain.
If unused, keep it
open.
USB_BOOT Interface
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
USB_BOOT
115
DI
Force the module to
enter into
emergency
download mode.
VILmin=-0.3V
VILmax=0.6V
VIHmin=1.2V
VIHmax=2.0V
1.8V power domain.
Active high.
If unused, keep it
open.
RESERVED Pins
Pin Name
Pin No.
I/O
Description
DC Characteristics
Comment
RESERVED
3, 18, 23,
43, 55,
73~84,
113, 114,
116, 117,
140-144.
Reserved
Keep these pins
unconnected.
NOTES
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Minimum
Functionality
Mode
AT+CFUN command can set the module to a minimum functionality mode without
removing the power supply. In this case, both RF function and (U)SIM card will be invalid.
Airplane
Mode
AT+CFUN command or W_DISABLE# pin can set the module to airplane mode. In this
case, RF function will be invalid.
Sleep Mode
In this mode, the current consumption of the module will be reduced to the minimal level.
During this mode, the module can still receive paging message, SMS, voice call and
TCP/UDP data from the network normally.
Power down
Mode
In this mode, the power management unit shuts down the power supply. Software is not
active. The serial interface is not accessible. Operating voltage (connected to VBAT_RF
and VBAT_BB) remains applied.
3.4. Power Saving
3.4.1. Sleep Mode
EC21 is able to reduce its current consumption to a minimum value during the sleep mode. The following
section describes power saving procedures of EC21 module.
3.4.1.1. UART Application
If the host communicates with module via UART interface, the following preconditions can let the module
enter into sleep mode.
Execute AT+QSCLK=1 command to enable sleep mode.
Drive DTR to high level.
The following figure shows the connection between the module and the host.
Figure 3: Sleep Mode Application via UART
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