Quectel EC25 series Supplement

EC25 Mini PCIe
Hardware Design
LTE Module Series
Rev. EC25_Mini_PCIe_Hardware_Design_V1.1
Date: 2017-01-24
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About the Document
History
Revision
Date
Author
Description
1.0
2016-06-07
Mountain ZHOU/
Frank WANG
Initial
1.1
2017-01-24
Lyndon LIU/
Frank WANG
1. Deleted description of EC25-AUT Mini PCIe
in Table 1.
2. Added description of EC25-AU and EC25-J
Mini PCIe in Table 1.
3. Updated key features of EC25 Mini PCIe in
Table 2.
4. Added current consumption in Chapter 4.7.
5. Updated conducted RF receiving sensitivity
of EC25-AMini PCIe in Table 17.
6. Added conducted RF receiving sensitivity of
EC25-J Mini PCIe in Table 18.
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Contents
About the Document...................................................................................................................................2
Contents.......................................................................................................................................................3
Table Index...................................................................................................................................................5
Figure Index.................................................................................................................................................6
1Introduction..........................................................................................................................................7
1.1. Safety Information......................................................................................................................8
2Product Concept..................................................................................................................................9
2.1. General Description...................................................................................................................9
2.2. Description of Product Series..................................................................................................10
2.3. Key Features ........................................................................................................................... 11
2.4. Functional Diagram .................................................................................................................13
3Application Interface .........................................................................................................................14
3.1. General Description.................................................................................................................14
3.2. EC25 Mini PCIe Interface........................................................................................................14
3.2.1. Definition of Interface.....................................................................................................14
3.2.2. Pin Assignment ..............................................................................................................17
3.3. Power Supply...........................................................................................................................18
3.4. USIM Card Interface................................................................................................................19
3.5. USB Interface ..........................................................................................................................20
3.6. UART Interface........................................................................................................................21
3.7. PCM and I2C Interfaces..........................................................................................................22
3.8. Control Signals ........................................................................................................................24
3.8.1. RI Signal.........................................................................................................................25
3.8.2. DTR Signal.....................................................................................................................25
3.8.3. W_DISABLE# Signal......................................................................................................25
3.8.4. PERST# Signal..............................................................................................................25
3.8.5. LED_WWAN# Signal .....................................................................................................26
3.8.6. WAKE# Signal................................................................................................................27
3.9. Antenna Interfaces ..................................................................................................................27
4Electrical and Radio Characteristics ...............................................................................................29
4.1. General Description.................................................................................................................29
4.2. Power Supply Requirements...................................................................................................29
4.3. I/O Requirements.....................................................................................................................30
4.4. RF Characteristics...................................................................................................................30
4.5. GNSS Receiver .......................................................................................................................32
4.6. ESD Characteristics ................................................................................................................33
4.7. Current Consumption ..............................................................................................................33
5Dimensions and Packaging..............................................................................................................38
5.1. General Description.................................................................................................................38
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5.2. Mechanical Dimensions of EC25 Mini PCIe............................................................................38
5.3. Standard Dimensions of Mini PCI Express .............................................................................39
5.4. Packaging Specification...........................................................................................................40
6Appendix References........................................................................................................................41
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Table Index
TABLE 1: DESCRIPTION OF EC25 MINI PCIE................................................................................................ 10
TABLE 2: KEY FEATURES OF EC25 MINI PCIE..............................................................................................11
TABLE 3: DEFINITION OF I/O PARAMETERS................................................................................................. 14
TABLE 4: DESCRIPTION OF PINS .................................................................................................................. 15
TABLE 5: DEFINITION OF VCC_3V3 AND GND PINS.................................................................................... 18
TABLE 6: USIM PIN DEFINITION..................................................................................................................... 19
TABLE 7: PIN DEFINITION OF USB INTERFACE ........................................................................................... 20
TABLE 8: PIN DEFINITION OF THE UART INTERFACE................................................................................. 21
TABLE 9: PIN DEFINITION OF PCM AND I2C INTERFACES......................................................................... 22
TABLE 10: PIN DEFINITION OF CONTROL SIGNALS.................................................................................... 24
TABLE 11: RADIO OPERATIONAL STATES..................................................................................................... 25
TABLE 12: INDICATIONS OF NETWORK STATUS......................................................................................... 26
TABLE 13: ANTENNA REQUIREMENTS.......................................................................................................... 27
TABLE 14: POWER SUPPLY REQUIREMENTS.............................................................................................. 29
TABLE 15: I/O REQUIREMENTS...................................................................................................................... 30
TABLE 16: EC25 MINI PCIE CONDUCTED RF OUTPUT POWER................................................................. 30
TABLE 17: EC25-A MINI PCIE CONDUCTED RF RECEIVING SENSITIVITY................................................ 31
TABLE 18: EC25-J MINI PCIE CONDUCTED RF RECEIVING SENSITIVITY ................................................ 31
TABLE 19: EC25-E MINI PCIE CONDUCTED RF RECEIVING SENSITIVITY................................................ 32
TABLE 20: EC25-V MINI PCIE CONDUCTED RF RECEIVING SENSITIVITY................................................ 32
TABLE 21: ESD CHARACTERISTICS OF EC25 MINI PCIE............................................................................ 33
TABLE 22: CURRENT CONSUMPTION OF EC25-A MINI PCIE ..................................................................... 33
TABLE 23: CURRENT CONSUMPTION OF EC25-E MINI PCIE..................................................................... 34
TABLE 24: CURRENT CONSUMPTION OF EC25-V MINI PCIE..................................................................... 37
TABLE 25: GNSS CURRENT CONSUMPTION OF EC25 MINI PCIE SERIES MODULE............................... 37
TABLE 26: RELATED DOCUMENTS................................................................................................................ 41
TABLE 27: TERMS AND ABBREVIATIONS...................................................................................................... 41
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Figure Index
FIGURE 1: FUNCTIONAL DIAGRAM ............................................................................................................... 13
FIGURE 2: PIN ASSIGNMENT ......................................................................................................................... 17
FIGURE 3: REFERENCE DESIGN OF POWER SUPPLY ............................................................................... 18
FIGURE 4: REFERENCE CIRCUIT OF USIM CARD INTERFACE WITH A 6-PIN USIM CARD CONNECTOR
........................................................................................................................................................................... 19
FIGURE 5: REFERENCE CIRCUIT OF USB INTERFACE .............................................................................. 20
FIGURE 6: TIMING IN PRIMARY MODE.......................................................................................................... 23
FIGURE 7: TIMING IN AUXILIARY MODE........................................................................................................ 23
FIGURE 8: REFERENCE CIRCUIT OF PCM APPLICATION WITH AUDIO CODEC...................................... 24
FIGURE 9: RI BEHAVIOR................................................................................................................................. 25
FIGURE 10: TIMING OF RESETTING MODULE ............................................................................................. 26
FIGURE 11: LED_WWAN# SIGNAL REFERENCE CIRCUIT DIAGRAM......................................................... 26
FIGURE 12: WAKE# BEHAVIOR...................................................................................................................... 27
FIGURE 13: DIMENSIONS OF THE RF CONNECTOR (UNIT: MM) ............................................................... 28
FIGURE 14: MECHANICALS OF U.FL-LP CONNECTORS............................................................................. 28
FIGURE 15: MECHANICAL DIMENSIONS OF EC25 MINI PCIE (UNIT: MM)................................................. 38
FIGURE 16: STANDARD DIMENSIONS OF MINI PCI EXPRESS (UNIT: MM)............................................... 39
FIGURE 17: DIMENSIONS OF THE MINI PCI EXPRESS CONNECTOR (MOLEX 679100002, UNIT: MM).. 40
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1Introduction
This document defines EC25 Mini PCIe module, and describes its hardware interfaces which are
connected with your application as well as its air interfaces.
This document can help you to quickly understand the interface specifications, electrical and mechanical
details as well as other related information of EC25 Mini PCIe module. To facilitate its application in
different fields, relevant reference design documents are also provided. Associated with application note
and user guide of EC25 Mini PCIe module, you can use the 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 EC25 Mini PCIe 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 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 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
EC25 Mini PCIe module provides data connectivity on LTE-FDD, LTE-TDD, WCDMA and GSM networks
with PCI Express Mini Card 1.2 standard interface. It supports embedded operating systems such as
WinCE, Linux, Android, etc., and also provides audio, high-speed data transmission and GNSS
functionalities for your applications.
EC25 Mini PCIe module can be applied in the following fields:
PDA and Laptop Computer
Remote Monitor System
Vehicle System
Wireless POS System
Intelligent Meter Reading System
Wireless Router and Switch
Other Wireless Terminal Devices
This chapter generally introduces the following aspects of EC25 Mini PCIe module:
Product Series
Key Features
Functional Diagram

EC25 Mini PCIe contains Telematics version and Data-only version. Telematics version supports voice
and data functions, while Data-only version only supports data function.
NOTE
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2.2. Description of Product Series
The following table shows the product series of EC25 Mini PCIe module.
Table 1: Description of EC25 Mini PCIe
1. 1) GNSS function is optional.
2. 2) Digital audio (PCM) function is only supported in Telematics version.
Product Series
Description
EC25-A Mini PCIe
Support WCDMA: B2/B4/B5
Support LTE-FDD: B2/B4/B12
Support LTE/WCDMA receive diversity
Support GNSS1)
Support digital audio2)
EC25-AU Mini PCIe3)
Support GSM: 850/900/1800/1900MHz
Support WCDMA: B1/B2/B5/B8
Support LTE-FDD: B1/B2/B3/B4/B5/B7/B8/B28
Support LTE-TDD: B40
Support LTE/WCDMA receive diversity3)
Support GNSS1)
Support digital audio2)
EC25-J Mini PCIe
Support WCDMA: B1/B6/B8/B19
Support LTE-FDD: B1/B3/B8/B18/B19/B26
Support LTE-TDD: B41
Support LTE/WCDMA receive diversity
Support GNSS1)
Support digital audio2)
EC25-E Mini PCIe
Support GSM: 900/1800MHz
Support WCDMA: B1/B5/B8
Support LTE-FDD: B1/B3/B5/B7/B8/B20
Support LTE-TDD: B38/B40/B41
Support LTE/WCDMA receive diversity
Support GNSS1)
Support digital audio2)
EC25-V Mini PCIe
Support LTE-FDD: B4/B13
Support LTE receive diversity
Support GNSS1)
Support digital audio2)
NOTES
SS
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3. 3) B2 band on EC25-AU Mini PCIe module does not support receive diversity.
2.3. Key Features
The following table describes the detailed features of EC25 Mini PCIe module.
Table 2: Key Features of EC25 Mini PCIe
Feature
Details
Function Interface
PCI Express Mini Card 1.2 Standard Interface
Power Supply
Supply voltage: 3.0~3.6V
Typical supply voltage: 3.3V
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-CACat 4
Support 1.4 to 20MHz RF bandwidth
Support MIMO in DL direction
FDD: Max 50Mbps (UL), 150Mbps (DL)
TDD: Max 35Mbps (UL), 130Mbps (DL)
WCDMA Features
Support 3GPP R8 DC-HSPA+
Support 16-QAM, 64-QAM and QPSK modulation
3GPP R6 Cat 6 HSUPA: Max 5.76Mbps (UL)
3GPP R8 Cat 24 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
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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, MCS 1-9
Uplink coding schemes: CS 1-4, MCS 1-9
Internet Protocol Features
Support TCP/UDP/PPP/FTP/HTTP/NTP/PING/QMI/HTTPS*/SMTP*/
MMS*/FTPS*/SMTPS*/SSL* protocols
Support the protocols PAP (Password Authentication Protocol) and CHAP
(Challenge Handshake Authentication Protocol) 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
UART Interface
Baud rate can reach up to 230400bps, 115200bps by default
Used for AT command communication
Audio Feature
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
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 mode, 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, firmware
upgrade, software debugging, GNSS NMEA output and voice over USB*
USB Driver: Windows XP, Windows Vista, Windows 7, Windows 8/8.1,
Windows 10, Linux 2.6 or later, Android 4.0/4.2/4.4/5.0/5.1/6.0
Antenna Interface
Include main antenna, diversity antenna and GNSS antenna
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
Physical Characteristics
Size: (51.0±0.1) ×(30.0±0.1) ×(4.9±0.2 mm)
Weight: approx. 9.8g
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1. “*” means under development.
2. 1) Within operating temperature range, the module is 3GPP compliant.
3. 2) Within extended temperature range, the module remains the ability to establish and maintain a
voice, SMS, data transmission, emergency call, etc. There is no unrecoverable malfunction; there are
also no effects on radio spectrum and no harm to radio network. Only one or more parameters like
Pout might reduce in their value and exceed the specified tolerances. When the temperature returns
to normal operating temperature levels, the module is compliant with 3GPP specification again.
2.4. Functional Diagram
The following figure shows the block diagram of EC25 Mini PCIe.
EC25
Module
PCM&I2C
Mini PCI Express
Interface
USB
USIM
W_DISABLE#
PERST#
LED_WWAN#
Main
Antenna
Interface
VCC
Main
Antenna
VBAT
GNSS
Antenna
Interface
GNSS
Antenna
Boost
Circuit
Diversity
Antenna
Interface
Diversity
Antenna
WAKE#
UART
DTR
RI
Figure 1: Functional Diagram
Temperature Range
Operation temperature range: -35°C ~ +75°C 1)
Extended temperature range: -40°C ~ +80°C 2)
Firmware Upgrade
USB interface and DFOTA*
RoHS
All hardware components are fully compliant with EU RoHS directive
NOTES
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3Application Interface
3.1. General Description
The physical connections and signal levels of EC25 Mini PCIe comply with PCI Express Mini CEM
specifications. This chapter mainly describes the following interfaces’ definition and application of EC25
Mini PCIe:
Power supply
USIM card interface
USB interface
UART interface
PCM&I2C interfaces
Control signals
Antenna interface
3.2. EC25 Mini PCIe Interface
3.2.1. Definition of Interface
The following tables show the pin definition and description of EC25 Mini PCIe on the 52-pin application.
Table 3: Definition of I/O Parameters
Type
Description
IO
Bidirectional
DI
Digital input
DO
Digital output
OC
Open collector
PI
Power input
PO
Power output
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Table 4: Description of Pins
Pin No.
Mini PCI Express
Standard Name
EC25 Mini PCIe
Pin Name
I/O
Description
Comment
1
WAKE#
WAKE#
OC
Output signal can be used
to wake up the host.
2
3.3Vaux
VCC_3V3
PI
3.3V DC supply
3
COEX1
RESERVED
Reserved
4
GND
GND
Mini card ground
5
COEX2
RESERVED
Reserved
6
1.5V
NC
7
CLKREQ#
RESERVED
Reserved
8
UIM_PWR
USIM_VDD
PO
Power source for the USIM
card
9
GND
GND
Mini card ground
10
UIM_DATA
USIM_DATA
IO
USIM data signal
11
REFCLK-
UART_RX
DI
UART receive data
Connect to
DTE’s TX
12
UIM_CLK
USIM_CLK
DO
USIM clock signal
13
REFCLK+
UART_TX
DO
UART transmit data
Connect to
DTE’s RX
14
UIM_RESET
USIM_RST
DO
USIM reset signal
15
GND
GND
Mini card ground
16
UIM_VPP
RESERVED
Reserved
17
RESERVED
RI
DO
Output signal can be used
to wake up the host.
18
GND
GND
Mini card ground
19
RESERVED
RESERVED
Reserved
20
W_DISABLE#
W_DISABLE#
DI
Disable wireless
communications
Pull-up by
default
Active low
21
GND
GND
Mini card ground
22
PERST#
PERST#
DI
Functional reset to the card
Active low
23
PERn0
UART_CTS
DI
UART clear to send
Connect to
DTE’s RTS
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24
3.3Vaux
RESERVED
Reserved
25
PERp0
UART_RTS
DO
UART request to send
Connect to
DTE’s CTS
26
GND
GND
Mini card ground
27
GND
GND
Mini card ground
28
1.5V
NC
29
GND
GND
Mini card ground
30
SMB_CLK
I2C_SCL
DO
I2C serial clock
Require
external
pull-up to
1.8V.
31
PETn0
DTR
DI
Sleep mode control
32
SMB_DATA
I2C_SDA
IO
I2C serial data
Require
external
pull-up to
1.8V.
33
PETp0
RESERVED
Reserved
34
GND
GND
Mini card ground
35
GND
GND
Mini card ground
36
USB_D-
USB_DM
IO
USB differential data (-)
37
GND
GND
Mini card ground
38
USB_D+
USB_DP
IO
USB differential data (+)
39
3.3Vaux
VCC_3V3
PI
3.3V DC supply
40
GND
GND
Mini card ground
41
3.3Vaux
VCC_3V3
PI
3.3V DC supply
42
LED_WWAN#
LED_WWAN#
OC
Active-low. LED signal for
indicating the state of the
card.
43
GND
GND
Mini card ground
44
LED_WLAN#
RESERVED
Reserved
45
RESERVED
PCM_CLK*
IO
PCM clock signal
46
LED_WPAN#
RESERVED
Reserved
47
RESERVED
PCM_DOUT*
DO
PCM data output
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1. Keep all NC, reserved and unused pins unconnected.
2. “*” means the digital audio (PCM) function is only supported on Telematics version.
3.2.2. Pin Assignment
The following figure shows the pin assignment of EC25 Mini PCIe module. The top side contains EC25
module and antenna connectors.
PIN2
PIN52
BOT
PIN1
PIN51
TOP
Figure 2: Pin Assignment
48
1.5V
NC
49
RESERVED
PCM_DIN*
DI
PCM data input
50
GND
GND
Mini card ground
51
RESERVED
PCM_SYNC*
IO
PCM frame synchronization
52
3.3Vaux
VCC_3V3
PI
3.3V DC supply
NOTES
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3.3. Power Supply
The following table shows pin definition of VCC_3V3 pins and ground pins.
Table 5: Definition of VCC_3V3 and GND Pins
The typical supply voltage of EC25 Mini PCIe is 3.3V. In the 2G networks, the input peak current may
reach to 2.7A during the transmitting time. Therefore, the power supply must be able to provide enough
current, and a bypass capacitor of no less than 470µF with low ESR should be used to prevent the
voltage from dropping.
The following figure shows a reference design of power supply. The precision of resistor R2 and R3 is 1%,
and the capacitor C3 needs a low ESR.
LDO_IN
C1 C2
MIC29302WU U1
IN OUT
EN
GND
ADJ
2 4
1 3 5
VCC_3V3
100nF C3
470uF
C4
100nF
R2
82K 1%
47K 1%
R3
470uF
470R
51K R4
R1
MCU_POWER
_ON/OFF 47K
4.7K
R5
R6
C5 C6
33pF 10pF
TVS
D1
Figure 3: Reference Design of Power Supply
Pin No.
Pin Name
I/O
Power Domain
Description
2, 39, 41, 52
VCC_3V3
PI
3.0~3.6V
3.3V DC supply
4, 9, 15, 18, 21,
26, 27, 29, 34, 35,
37, 40, 43, 50
GND
Mini card ground
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LTE Module Series
EC25 Mini PCIe Hardware Design
EC25_Mini_PCIe_Hardware_Design Confidential / Released 19 / 42
3.4. USIM Card Interface
The following table shows the pin definition of USIM card interface.
Table 6: USIM Pin Definition
EC25 Mini PCIe supports 1.8V and 3.0V USIM cards. The following figure shows a reference design for a
6-pin USIM card connector.
USIM_VDD
GND
USIM_RST
USIM_CLK
USIM_DATA 22R
22R
22R
100nF
USIM Card Connector
GND
33pF 33pF33pF
VCC
RST
CLK IO
VPP
GND
GND
33pF
15K
Module USIM_VDD
Figure 4: Reference Circuit of USIM Card Interface with a 6-Pin USIM Card Connector
In order to enhance the reliability and availability of the USIM card in your application, please follow the
criteria below in USIM circuit design:
Keep layout of USIM card as close to the module as possible. Keep the trace length as less than
200mm as possible.
Keep USIM card signal away from RF and power supply traces.
Keep the trace width of ground and USIM_VDD no less than 0.5mm to maintain the same electric
potential. The decouple capacitor of USIM_VDD should be less than 1uF and must near to USIM
card connector.
Pin No.
Pin Name
I/O
Power Domain
Description
8
USIM_VDD
PO
1.8V/3.0V
Power source for the USIM card
10
USIM_DATA
IO
1.8V/3.0V
USIM data signal
12
USIM_CLK
DO
1.8V/3.0V
USIM clock signal
14
USIM_RST
DO
1.8V/3.0V
USIM reset signal
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