Quectel Wireless Solutions 201808EC25AF Users Manual

EC25 Hardware Design

LTE Module Series

Rev. EC25_Hardware_Design_V1.5

Date: 2018-04-20

Status: Released

www.quectel.com

LTE Module Series

EC25 Hardware Design

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QUECTEL OFFERS THE INFORMATION AS A SERVICE TO ITS CUSTOMERS. THE INFORMATION PROVIDED IS BASED UPON CUSTOMERS’ REQUIREMENTS. QUECTEL MAKES EVERY EFFORT TO ENSURE THE QUALITY OF THE INFORMATION IT MAKES AVAILABLE. QUECTEL DOES NOT MAKE ANY WARRANTY AS TO THE INFORMATION CONTAINED HEREIN, AND DOES NOT ACCEPT ANY LIABILITY FOR ANY INJURY, LOSS OR DAMAGE OF ANY KIND INCURRED BY USE OF OR RELIANCE UPON THE INFORMATION. ALL INFORMATION SUPPLIED HEREIN IS SUBJECT TO CHANGE WITHOUT PRIOR NOTICE.

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Copyright © Quectel Wireless Solutions Co., Ltd. 2018. All rights reserved.

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About the Document

History

Revision	Date		Author	Description
1.0	2016-04-01		Woody WU	Initial
				1.	Updated EC25 series frequency bands in Table 1.
				2.	Updated transmitting power, supported maximum
					baud rate of main UART/internal protocols/USB
					drivers of USB interface, firmware upgrade 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.
1.1	2016-09-22		Lyndon LIU/	5.	Updated timing of resetting module in Figure 16.
			Frank WANG	6.	Updated supported baud rates of main UART 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.	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
	1.2		2016-11-04	Lyndon LIU/		Table 4.
				Michael ZHANG	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 note about SIMO in Chapter 6.6.
	1.3		2017-01-24	Lyndon LIU/	1.	Updated function diagram in Figure 1.
				Frank WANG	2.	Updated pin assignment (top view) in Figure 2.
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					3.	Added BT interface in Chapter 3.18.2.
					4.	Updated GNSS performance in Table 24.
					5.	Updated reference circuit of wireless connectivity
						interfaces with FC20 module in Figure 29.
					6.	Updated current consumption of EC25-E module in
						Table 33.
					7.	Updated EC25-A conducted RF receiving sensitivity
						in Table 38.
					8.	AddedEC25-J conducted RF receiving sensitivity in
						Table 40.
					1.	Updated functional diagram in Figure 1.
					2.	Updated frequency bands in Table 1.
					3.	Updated LTE, 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.	Added SD card interface in Chapter 3.13.
				AnniceZHANG/	10.	Updated USB_BOOT reference circuit in Chapter
						3.20.
1.4		2018-03-05		Lyndon LIU/
					11.	Updated module operating frequencies in Table 26.
				Frank WANG
					12.	Updated antenna requirements in Table 30.
					13.	Updated EC25 series module current consumption in
						Chapter 6.4.
					14.	Updated EC25 series module conducted RF receiving
						sensitivity in Chapter 6.6.
					15.	Added thermal consideration description in Chapter
						6.8.
					16.	Added dimension tolerance information in Chapter 7.
					17.	Added storage temperature range in Table 2 and
						Chapter 6.3.
					18.	Updated RF output power in Table 41.
					19.	Updated GPRS multi-slot classes in Table 53.
					20.	Updated storage information in Chapter 8.1.
					1.	Added information of EC25-AF in Table 1.
					2.	Updated module operating frequencies in Table 27.
1.5		2018-04-20		Kinsey ZHANG	3.	Added current consumption of EC25-AF module in
						Table 40.
					4.	Changed GNSS current consumption of EC25 series
						module into Table 41.
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5.Added EC25-AF conducted RF receiving sensitivity in Table 50.

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Contents

About the Document ................................................................................................................................				2
Contents		....................................................................................................................................................		5
Table Index ...............................................................................................................................................				8
Figure Index............................................................................................................................................				10
1	Introduction .....................................................................................................................................			12
	1.1. .................................................................................................................	Safety Information		13
2	Product .............................................................................................................................Concept			14
	2.1. ..............................................................................................................	General Description		14
	2.2. .........................................................................................................................	Key Features		15
	2.3. ...............................................................................................................	Functional Diagram		18
	2.4. ...................................................................................................................	Evaluation Board		19
3	Application .....................................................................................................................Interfaces			20
	3.1. ..............................................................................................................	General Description		20
	3.2. .....................................................................................................................	Pin Assignment		21
	3.3. ......................................................................................................................	Pin Description		22
	3.4. ..................................................................................................................	Operating Modes		34
	3.5. ........................................................................................................................	Power Saving		34
	3.5.1. ..................................................................................................................		Sleep Mode	34
	..............................................................................................	3.5.1.1. UART Application		34
	.......................................	3.5.1.2. USB Application with USB Remote Wakeup Function		35
	..........................	3.5.1.3. USB Application with USB Suspend/Resume and RI Function		36
	..............................................	3.5.1.4. USB Application without USB Suspend Function		37
	3.5.2. ..............................................................................................................		Airplane Mode	37
	3.6. ........................................................................................................................	Power Supply		38
	3.6.1. .......................................................................................................		Power Supply Pins	38
	3.6.2. ...............................................................................................		Decrease Voltage Drop	39
	3.6.3. ............................................................................Reference Design for Power Supply			40
	3.6.4. ............................................................................................Monitor the Power Supply			40
	3.7. .....................................................................................................	Turn on and off Scenarios		40
	3.7.1. ...........................................................................Turn on Module Using the PWRKEY			40
	3.7.2. ............................................................................................................		Turn off Module	42
	...........................................................	3.7.2.1. Turn off Module Using the PWRKEY Pin		42
	................................................................	3.7.2.2. Turn off Module Using AT Command		43
	3.8. ..................................................................................................................	Reset the Module		43
	3.9. ....................................................................................................................	(U)SIM Interface		45
	3.10. ........................................................................................................................	USB Interface		47
	3.11. ...................................................................................................................	UART Interfaces		49
	3.12. ........................................................................................................	PCM and I2C Interfaces		51
	3.13. .................................................................................................................	SD Card Interface		54
	3.14. ......................................................................................................................	ADC Interfaces		56
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	3.15.	Network Status Indication .....................................................................................................			57
	3.16.	STATUS................................................................................................................................			58
	3.17.	Behaviors of RI .....................................................................................................................			59
	3.18.	SGMII Interface.....................................................................................................................			60
	3.19.	Wireless Connectivity Interfaces ...........................................................................................			62
	3.19.1.		WLAN Interface ...........................................................................................................		64
	3.19.2.		BT Interface*................................................................................................................		64
	3.20.	USB_BOOT Interface............................................................................................................			65
4	GNSS Receiver ................................................................................................................................				66
	4.1.	General Description ..............................................................................................................			66
	4.2.	GNSS Performance ..............................................................................................................			66
	4.3.	Layout Guidelines .................................................................................................................			67
5	Antenna Interfaces..........................................................................................................................				68
	5.1.	Main/Rx-diversity Antenna Interfaces....................................................................................			68
	5.1.1.		Pin Definition................................................................................................................		68
	5.1.2.		Operating Frequency ...................................................................................................		68
	5.1.3. Reference Design of RF Antenna Interface .................................................................				70
	5.1.4. Reference Design of RF Layout...................................................................................				70
	5.2.	GNSS Antenna Interface.......................................................................................................			72
	5.3.	Antenna Installation ..............................................................................................................			74
	5.3.1.		Antenna Requirement..................................................................................................		74
	5.3.2. Recommended RF Connector for Antenna Installation................................................				75
6	Electrical, Reliability and Radio Characteristics ..........................................................................				77
	6.1.	Absolute Maximum Ratings ..................................................................................................			77
	6.2.	Power Supply Ratings...........................................................................................................			78
	6.3.	Operation and Storage Temperatures ..................................................................................			78
	6.4.	Current Consumption............................................................................................................			79
	6.5.	RF Output Power ..................................................................................................................			90
	6.6.	RF Receiving Sensitivity .......................................................................................................			91
	6.7.	Electrostatic Discharge .........................................................................................................			95
	6.8.	Thermal Consideration..........................................................................................................			95
7	Mechanical Dimensions..................................................................................................................				98
	7.1.	Mechanical Dimensions of the the Module............................................................................			98
	7.2.	Recommended Footprint.....................................................................................................			100
	7.3.	Design Effect Drawings of the Module ................................................................................			101
8	Storage, Manufacturing and Packaging......................................................................................				102
	8.1.	Storage ...............................................................................................................................			102
	8.2.	Manufacturing and Soldering ..............................................................................................			103
	8.3.	Packaging ...........................................................................................................................			104
9	Appendix A References................................................................................................................				105
10	Appendix B GPRS Coding Schemes ...........................................................................................				109

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11	Appendix C GPRS Multi-slot Classes..........................................................................................	110
12	Appendix D EDGE Modulationand Coding Schemes.................................................................	112

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Table Index
TABLE 1: FREQUENCY BANDS OF EC25 SERIES MODULE .......................................................................	14
TABLE 2: KEY FEATURES OF EC25 MODULE ..............................................................................................	15
TABLE 3: I/O PARAMETERS DEFINITION ......................................................................................................	22
TABLE 4: PIN DESCRIPTION...........................................................................................................................	22
TABLE 5: OVERVIEW OF OPERATING MODES ............................................................................................	34
TABLE 6: VBAT AND GND PINS......................................................................................................................	38
TABLE 7: PIN DEFINITION OF PWRKEY ........................................................................................................	41
TABLE 8: RESET_N PIN DESCRIPTION.........................................................................................................	43
TABLE 9: PIN DEFINITION OF THE (U)SIM INTERFACE...............................................................................	45
TABLE 10: PIN DESCRIPTION OF USB INTERFACE.....................................................................................	47
TABLE 11: PIN DEFINITION OF MAIN UART INTERFACE ............................................................................	49
TABLE 12: PIN DEFINITION OF DEBUG UART INTERFACE.........................................................................	49
TABLE 13: LOGIC LEVELS OF DIGITAL I/O ...................................................................................................	50
TABLE 14: PIN DEFINITION OF PCM AND I2C INTERFACES ......................................................................	52
TABLE 15: PIN DEFINITION OF SD CARD INTERFACE................................................................................	54
TABLE 16: PIN DEFINITION OF ADC INTERFACES ......................................................................................	56
TABLE 17: CHARACTERISTIC OF ADC..........................................................................................................	56
TABLE 18: PIN DEFINITION OF NETWORK CONNECTION STATUS/ACTIVITY INDICATOR ....................	57
TABLE 19: WORKING STATE OF THE NETWORK CONNECTION STATUS/ACTIVITY INDICATOR .........	57
TABLE 20: PIN DEFINITION OF STATUS .......................................................................................................	58
TABLE 21: BEHAVIOR OF RI ...........................................................................................................................	59
TABLE 22: PIN DEFINITION OF THE SGMII INTERFACE..............................................................................	60
TABLE 23: PIN DEFINITION OF WIRELESS CONNECTIVITY INTERFACES ...............................................	62
TABLE 24: PIN DEFINITION OF USB_BOOT INTERFACE.............................................................................	65
TABLE 25: GNSS PERFORMANCE.................................................................................................................	66
TABLE 26: PIN DEFINITION OF RF ANTENNA...............................................................................................	68
TABLE 27: MODULE OPERATING FREQUENCIES .......................................................................................	68
TABLE 28: PIN DEFINITION OF GNSS ANTENNA INTERFACE....................................................................	72
TABLE 29: GNSS FREQUENCY ......................................................................................................................	73
TABLE 30: ANTENNA REQUIREMENTS.........................................................................................................	74
TABLE 31: ABSOLUTE MAXIMUM RATINGS .................................................................................................	77
TABLE 32: THE MODULE POWER SUPPLY RATINGS..................................................................................	78
TABLE 33: OPERATION AND STORAGE TEMPERATURES.........................................................................	78
TABLE 34: EC25-E CURRENT CONSUMPTION.............................................................................................	79
TABLE 35: EC25-A CURRENT CONSUMPTION.............................................................................................	81
TABLE 36: EC25-V CURRENT CONSUMPTION.............................................................................................	82
TABLE 37: EC25-J CURRENT CONSUMPTION .............................................................................................	83
TABLE 38: EC25-AU CURRENT CONSUMPTION ..........................................................................................	84
TABLE 39: EC25-AUT CURRENT CONSUMPTION ........................................................................................	87
TABLE 40: EC25-AF CURRENT CONSUMPTION...........................................................................................	88
TABLE 41: GNSS CURRENT CONSUMPTION OF EC25 SERIES MODULE ................................................	90

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TABLE 42: RF OUTPUT POWER .....................................................................................................................	90
TABLE 43: EC25-E CONDUCTED RF RECEIVING SENSITIVITY..................................................................	91
TABLE 44: EC25-A CONDUCTED RF RECEIVING SENSITIVITY..................................................................	91
TABLE 45: EC25-V CONDUCTED RF RECEIVING SENSITIVITY..................................................................	92
TABLE 46: EC25-J CONDUCTED RF RECEIVING SENSITIVITY ..................................................................	92
TABLE 47: EC25-AU CONDUCTED RF RECEIVING SENSITIVITY ...............................................................	93
TABLE 48: EC25-AUT CONDUCTED RF RECEIVING SENSITIVITY.............................................................	93
TABLE 49: EC25-AUTL CONDUCTED RF RECEIVING SENSITIVITY...........................................................	94
TABLE 50: EC25-AF CONDUCTED RF RECEIVING SENSITIVITY ...............................................................	94
TABLE 51: ELECTROSTATICS DISCHARGE CHARACTERISTICS ..............................................................	95
TABLE 52: RELATED DOCUMENTS .............................................................................................................	105
TABLE 53: TERMS AND ABBREVIATIONS...................................................................................................	105
TABLE 54: DESCRIPTION OF DIFFERENT CODING SCHEMES................................................................	109
TABLE 55: GPRS MULTI-SLOT CLASSES....................................................................................................	110
TABLE 56: EDGE MODULATION AND CODING SCHEMES........................................................................	112

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Figure Index
FIGURE 1: FUNCTIONAL DIAGRAM ...............................................................................................................	19
FIGURE 2: PIN ASSIGNMENT (TOP VIEW) ....................................................................................................	21
FIGURE 3: SLEEP MODE APPLICATION VIA UART ......................................................................................	35
FIGURE 4: SLEEP MODE APPLICATION WITH USB REMOTE WAKEUP....................................................	36
FIGURE 5: SLEEP MODE APPLICATION WITH RI.........................................................................................	36
FIGURE 6: SLEEP MODE APPLICATION WITHOUT SUSPEND FUNCTION................................................	37
FIGURE 7: POWER SUPPLY LIMITS DURING BURST TRANSMISSION .....................................................	39
FIGURE 8: STAR STRUCTURE OF THE POWER SUPPLY...........................................................................	39
FIGURE 9: REFERENCE CIRCUIT OF POWER SUPPLY ..............................................................................	40
FIGURE 10: TURN ON THE MODULE BY USING DRIVING CIRCUIT...........................................................	41
FIGURE 11: TURN ON THE MODULE BY USING BUTTON...........................................................................	41
FIGURE 12: TIMING OF TURNING ON MODULE ...........................................................................................	42
FIGURE 13: TIMING OF TURNING OFF MODULE .........................................................................................	43
FIGURE 14: REFERENCE CIRCUIT OF RESET_N BY USING DRIVING CIRCUIT ......................................	44
FIGURE 15: REFERENCE CIRCUIT OF RESET_N BY USING BUTTON ......................................................	44
FIGURE 16: TIMING OF RESETTING MODULE .............................................................................................	44
FIGURE 17: REFERENCE CIRCUIT OF (U)SIM INTERFACE WITH AN 8-PIN (U)SIM CARD CONNECTOR
...................................................................................................................................................................	46
FIGURE 18: REFERENCE CIRCUIT OF (U)SIM INTERFACE WITH A 6-PIN (U)SIM CARD CONNECTOR 46
FIGURE 19: REFERENCE CIRCUIT OF USB APPLICATION.........................................................................	48
FIGURE 20: REFERENCE CIRCUIT WITH TRANSLATOR CHIP...................................................................	50
FIGURE 21: REFERENCE CIRCUIT WITH TRANSISTOR CIRCUIT..............................................................	51
FIGURE 22: PRIMARY MODE TIMING ............................................................................................................	52
FIGURE 23: AUXILIARY MODE TIMING..........................................................................................................	52
FIGURE 24: REFERENCE CIRCUIT OF PCM APPLICATION WITH AUDIO CODEC ...................................	53
FIGURE 25: REFERENCE CIRCUIT OF SD CARD.........................................................................................	55
FIGURE 26: REFERENCE CIRCUIT OF THE NETWORK INDICATOR .........................................................	58
FIGURE 27: REFERENCE CIRCUITS OF STATUS ........................................................................................	59
FIGURE 28: SIMPLIFIED BLOCK DIAGRAM FOR ETHERNET APPLICATION.............................................	61
FIGURE 29: REFERENCE CIRCUIT OF SGMII INTERFACE WITH PHY AR8033 APPLICATION................	61
FIGURE 30: REFERENCE CIRCUIT OF WIRELESS CONNECTIVITY INTERFACES WITH FC20 MODULE
...................................................................................................................................................................	63
FIGURE 31: REFERENCE CIRCUIT OF USB_BOOT INTERFACE................................................................	65
FIGURE 32: REFERENCE CIRCUIT OF RF ANTENNA INTERFACE ............................................................	70
FIGURE 33: MICROSTRIP LINE DESIGN ON A 2-LAYER PCB .....................................................................	71
FIGURE 34: COPLANAR WAVEGUIDE LINE DESIGN ON A 2-LAYER PCB.................................................	71
FIGURE 35: COPLANAR WAVEGUIDE LINE DESIGN ON A 4-LAYER PCB (LAYER 3 AS REFERENCE
GROUND) ..................................................................................................................................................	71
FIGURE 36: COPLANAR WAVEGUIDE LINE DESIGN ON A 4-LAYER PCB (LAYER 4 AS REFERENCE
GROUND) ..................................................................................................................................................	72
FIGURE 37: REFERENCE CIRCUIT OF GNSS ANTENNA.............................................................................	73

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FIGURE 38: DIMENSIONS OF THE U.FL-R-SMT CONNECTOR (UNIT: MM) ...............................................	75
FIGURE 39: MECHANICALS OF U.FL-LP CONNECTORS.............................................................................	75
FIGURE 40: SPACE FACTOR OF MATED CONNECTOR (UNIT: MM) ..........................................................	76
FIGURE 41: REFERENCED HEATSINK DESIGN (HEATSINK AT THE TOP OF THE MODULE).................	96
FIGURE 42: REFERENCED HEATSINK DESIGN (HEATSINK AT THE BACKSIDE OF CUSTOMERS’ PCB)
...................................................................................................................................................................	96
FIGURE 43: MODULE TOP AND SIDE DIMENSIONS ....................................................................................	98
FIGURE 44: MODULE BOTTOM DIMENSIONS (BOTTOM VIEW) .................................................................	99
FIGURE 45: RECOMMENDED FOOTPRINT (TOP VIEW)............................................................................	100
FIGURE 46: TOP VIEW OF THE MODULE....................................................................................................	101
FIGURE 47: BOTTOM VIEW OF THE MODULE............................................................................................	101
FIGURE 48: REFLOW SOLDERING THERMAL PROFILE............................................................................	103
FIGURE 49: TAPE AND REEL SPECIFICATIONS ........................................................................................	104

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1 Introduction

This document defines the EC25 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 EC25 module. Associated with application note and user guide, customers can use EC25 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 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 hands free 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 (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

EC25 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 application. EC25 contains seven variants: EC25-E, EC25-A, EC25-V, EC25-J, EC25-AU, EC25-AUT, EC25-AF and EC25-AUTL. Customers can choose a dedicated type based on the region or operator. The following table shows the frequency bands of EC25 series module.

Table 1: Frequency Bands of EC25 Series Module

	Modules2)		LTE Bands	WCDMA		GSM Bands	Rx-		GNSS1)
				Bands			diversity
	EC25-E		FDD: B1/B3/B5/B7/B8/B20	B1/B5/B8	900/1800MHz		Y
			TDD: B38/B40/B41
	EC25-A		FDD: B2/B4/B12	B2/B4/B5	N		Y
	EC25-V		FDD: B4/B13	N		N	Y		GPS,
			FDD: B1/B3/B8/B18/B19/						GLONASS,
	EC25-J		B26	B1/B6/B8/B19	N		Y		BeiDou/
			TDD: B41						Compass,
	EC25-AU3)		FDD: B1/B2/B3/B4/B5/B7/		850/900/				Galileo,
			B8/B28	B1/B2/B5/B8			Y		QZSS
						1800/1900MHz
			TDD: B40
	EC25-AUT		FDD: B1/B3//B5/B7/B28	B1/B5	N		Y
	EC25-AF		FDD: B2/B4//B5/B12/B13/	B2/B4/B5	N		Y
			B14/B66/B71
	EC25-AUTL		FDD: B3/B7/B28	N	N		Y		N

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NOTES

1. 1) GNSS function is optional.

2. 2) EC25 series module (EC25-E/EC25-A/EC25-V/EC25-J/EC25-AU/EC25-AUT/EC25-AF/ EC25-AUTL) 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 EC25-AU module does not support Rx-diversity.

4.Y = Supported. N = Not supported.

With a compact profile of 29.0mm × 32.0mm × 2.4mm, EC25 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.

EC25 is an SMD type module which can be embedded into applications through its 144-pin pads, including 80 LCC signal pads and 64 LGA pads.

2.2. Key Features

The following table describes the detailed features of EC25 module.

Table 2: Key Features of EC25 Module

		Feature		Details
		Power Supply		Supply voltage: 3.3V~4.3V
				Typical supply voltage: 3.8V
				Class 4 (33dBm±2dB) for GSM850
				Class 4 (33dBm±2dB) for EGSM900
				Class 1 (30dBm±2dB) for DCS1800
				Class 1 (30dBm±2dB) for PCS1900
				Class E2 (27dBm±3dB) for GSM850 8-PSK
		Transmitting Power		Class E2 (27dBm±3dB) for EGSM900 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
				Support up to non-CA Cat 4 FDD and TDD
		LTE Features		Support 1.4MHz~20MHz RF bandwidth
				Support MIMO in DL direction
				LTE-FDD: Max 150Mbps (DL)/50Mbps (UL)
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		LTE-TDD: Max 130Mbps (DL)/30Mbps (UL)
		Support 3GPP R8 DC-HSDPA, HSPA+, HSDPA, HSUPA and WCDMA
		Support QPSK, 16-QAM and 64-QAM modulation
	UMTS Features	DC-HSDPA: Max 42Mbps (DL)
		HSUPA: Max 5.76Mbps (UL)
		WCDMA: Max 384Kbps (DL)/384Kbps (UL)
		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:
	GSM Features	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)
		Support
		TCP/UDP/PPP/FTP/HTTP/NTP/PING/QMI/CMUX*/HTTPS*/SMTP*/
	Internet Protocol Features	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
		Text and PDU mode
	SMS	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
		Support one digital audio interface: PCM interface
		GSM: HR/FR/EFR/AMR/AMR-WB
	Audio Features	WCDMA: AMR/AMR-WB
		LTE: AMR/AMR-WB
		Support echo cancellation and noise suppression
		Used for audio function with external codec
		Support 16-bit linear data format
	PCM Interface	Support long frame synchronization and short frame synchronization
		Support master and slave modes, but must be the master in long frame
		synchronization
		Compliant with USB 2.0 specification (slave only); the data transfer rate can
	USB Interface	reach up to 480Mbps
		Used for AT command communication, data transmission, GNSS NMEA
		output, software debugging, firmware upgrade and voice over USB*
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		Support USB serial drivers for: Windows 7/8/8.1/10,
		Windows CE 5.0/6.0/7.0*, Linux 2.6/3.x/4.1~4.14, Android 4.x/5.x/6.x/7.x
		Main UART:
		Used for AT command communication and data transmission
		Baud rates reach up to 921600bps, 115200bps by default
	UART Interface	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 10M/100M/1000M Ethernet work mode
		Support maximum 150Mbps (DL)/50Mbps (UL) for 4G network
	Wireless Connectivity	Support a low-power SDIO 3.0 interface for WLAN and UART/PCM
	Interfaces	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 Interfaces	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
		Operation temperature range: -35°C ~ +75°C1)
	Temperature Range	Extended temperature range: -40°C ~ +85°C2)
		Storage temperature range: -40°C~ +90°C
	Firmware Upgrade	USB interface and DFOTA*
	RoHS	All hardware components are fully compliant with EU RoHS directive

NOTES

1. 1) Within operation temperature range, the module is 3GPP compliant.

2. 2) Within extended temperature range, the module remains the ability to establish and maintain 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 the normal operating temperature levels, the module will meet 3GPP specifications again.

3.“*” means under development.

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2.3. Functional Diagram

The following figure shows a block diagram of EC25 and illustrates the major functional parts.

Power management

Baseband

DDR+NAND flash

Radio frequency

Peripheral interfaces

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ANT_MAIN

ANT_GNSS ANT_DIV

		PAM		SAW		Switch
		Duplex		LNA
VBAT_RF						SAW
		PA
	APT
		PRx				DRx
		Tx
			Transceiver				NAND
							DDR2
							SDRAM
			IQ		Control
VBAT_BB	PMIC
		Control
PWRKEY
						Baseband
RESET_N
ADCs
STATUS		19.2M
		XO
	VDD_EXT	USB	USIM	PCM	I2C	UARTs	SGMII WLAN	BT*	GPIOs	SD

Figure 1: Functional Diagram

NOTE

“*” means under development.

2.4. Evaluation Board

In order to help customers develop applications with EC25, 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

EC25 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 Assignment

The following figure shows the pin assignment of EC25 module.

Figure 2: Pin Assignment (Top View)

NOTES

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. 3) means these interface functions are only supported on Telematics version.

4.Pads 37~40, 118, 127 and 129~139 are used for wireless connectivity interfaces, among which pads 118, 127 and 129~138 are WLAN function pins, and the rest are Bluetooth (BT) function pins. BT function is under development.

5.Pads 119~126 and 128 are used for SGMII interface.

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6.Pads 24~27 are multiplexing pins used for audio design on the EC25 module and BT function on the BT module.

7.Keep all RESERVED pins and unused pins unconnected.

8.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, and these pins should be served as a keep out area.

9.“*” means under development.

3.3. Pin Description

The following tables show the pin definition of EC25 modules.

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
			Power supply for	Vmax=4.3V	It must be able to
VBAT_BB	59, 60	PI	module’s baseband	Vmin=3.3V	provide sufficient
			part	Vnorm=3.8V	current up to 0.8A.

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								Vmax=4.3V	It must be able to
							Power supply for		provide sufficient
		VBAT_RF		57, 58		PI		Vmin=3.3V
							module’s RF part		current up to 1.8A in a
								Vnorm=3.8V
									burst transmission.
							Provide 1.8V for	Vnorm=1.8V	Power supply for
		VDD_EXT		7		PO			external GPIO’s pull-up
							external circuit	IOmax=50mA
									circuits.
				8, 9, 19,
				22, 36, 46,
		GND		48, 50~54,			Ground
				56, 72,
				85~112
		Turn on/off
		Pin Name		Pin No.		I/O	Description	DC Characteristics	Comment
								VIHmax=2.1V	The output voltage is
							Turn on/off the		0.8V because of the
		PWRKEY		21		DI		VIHmin=1.3V
							module		diode drop in the
								VILmax=0.5V
									Qualcomm chipset.
								VIHmax=2.1V	If unused, keep it
		RESET_N		20		DI	Reset the module	VIHmin=1.3V
									open.
								VILmax=0.5V
		Status Indication
		Pin Name		Pin No.		I/O	Description	DC Characteristics	Comment
							Indicate the module	The drive current	An external pull-up
		STATUS		61		OD		should be less than	resistor is required. If
							operating status
								0.9mA.	unused, keep it open.
									1.8V power domain.
							Indicate the module	VOHmin=1.35V	Cannot be pulled up
		NET_MODE		5		DO	network registration		before startup.
								VOLmax=0.45V
							mode		If unused, keep it
									open.
		NET_					Indicate the module	VOHmin=1.35V	1.8V power domain.
				6		DO	network activity		If unused, keep it
		STATUS						VOLmax=0.45V
							status		open.
		USB Interface
		Pin Name		Pin No.		I/O	Description	DC Characteristics	Comment
								Vmax=5.25V	Typical: 5.0V
		USB_VBUS		71		PI	USB detection	Vmin=3.0V	If unused, keep it
								Vnorm=5.0V	open.
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								Compliant with USB	Require differential
							USB differential data		impedance of 90Ω.
		USB_DP		69		IO		2.0 standard
							bus (+)		If unused, keep it
								specification.
									open.
								Compliant with USB	Require differential
							USB differential data		impedance of 90Ω.
		USB_DM		70		IO		2.0 standard
							bus (-)		If unused, keep it
								specification.
									open.
		(U)SIM Interface
		Pin Name		Pin No.		I/O Description		DC Characteristics	Comment
		USIM_GND		10			Specified ground for
							(U)SIM card
								VILmin=-0.3V	1.8V power domain.
		USIM_					(U)SIM card	VILmax=0.6V
				13		DI			If unused, keep it
		PRESENCE					insertion detection	VIHmin=1.2V
									open.
								VIHmax=2.0V
								For 1.8V(U)SIM:
								Vmax=1.9V
								Vmin=1.7V
							Power supply for		Either 1.8V or 3.0V is
		USIM_VDD		14		PO		For 3.0V(U)SIM:	supported by the
							(U)SIM card
								Vmax=3.05V	module automatically.
								Vmin=2.7V
								IOmax=50mA
								For 1.8V (U)SIM:
								VILmax=0.6V
								VIHmin=1.2V
								VOLmax=0.45V
							Data signal of	VOHmin=1.35V
		USIM_DATA		15		IO
							(U)SIM card
								For 3.0V (U)SIM:
								VILmax=1.0V
								VIHmin=1.95V
								VOLmax=0.45V
								VOHmin=2.55V
								For 1.8V (U)SIM:
								VOLmax=0.45V
							Clock signal of	VOHmin=1.35V
		USIM_CLK		16		DO
							(U)SIM card
								For 3.0V (U)SIM:
								VOLmax=0.45V
								VOHmin=2.55V
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						For 1.8V (U)SIM:
						VOLmax=0.45V
					Reset signal of	VOHmin=1.35V
		USIM_RST	17	DO
					(U)SIM card
						For 3.0V (U)SIM:
						VOLmax=0.45V
						VOHmin=2.55V
		Main UART Interface
		Pin Name	Pin No.	I/O	Description	DC Characteristics	Comment
						VOLmax=0.45V	1.8V power domain.
		RI	62	DO	Ring indicator		If unused, keep it
						VOHmin=1.35V
							open.
					Data carrier	VOLmax=0.45V	1.8V power domain.
		DCD	63	DO			If unused, keep it
					detection	VOHmin=1.35V
							open.
						VOLmax=0.45V	1.8V power domain.
		CTS	64	DO	Clear to send		If unused, keep it
						VOHmin=1.35V
							open.
						VILmin=-0.3V	1.8V power domain.
						VILmax=0.6V
		RTS	65	DI	Request to send		If unused, keep it
						VIHmin=1.2V
							open.
						VIHmax=2.0V
							1.8V power domain.
						VILmin=-0.3V	Pulled up by default.
		DTR	66	DI	Data terminal ready,	VILmax=0.6V	Low level wakes up
					sleep mode control	VIHmin=1.2V	the module.
						VIHmax=2.0V	If unused, keep it
							open.
						VOLmax=0.45V	1.8V power domain.
		TXD	67	DO	Transmit data		If unused, keep it
						VOHmin=1.35V
							open.
						VILmin=-0.3V	1.8V power domain.
						VILmax=0.6V
		RXD	68	DI	Receive data		If unused, keep it
						VIHmin=1.2V
							open.
						VIHmax=2.0V
		Debug UART Interface
		Pin Name	Pin No.	I/O	Description	DC Characteristics	Comment
						VOLmax=0.45V	1.8V power domain.
		DBG_TXD	12	DO	Transmit data		If unused, keep it
						VOHmin=1.35V
							open.
		DBG_RXD	11	DI	Receive data	VILmin=-0.3V	1.8V power domain.
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							VILmax=0.6V	If unused, keep it
							VIHmin=1.2V	open.
							VIHmax=2.0V
		ADC Interface
		Pin Name		Pin No.	I/O	Description	DC Characteristics	Comment
						General purpose	Voltage range:	If unused, keep it
		ADC0		45	AI	analog to digital
							0.3V to VBAT_BB	open.
						converter
						General purpose	Voltage range:	If unused, keep it
		ADC1		44	AI	analog to digital
							0.3V to VBAT_BB	open.
						converter
		PCM Interface
		Pin Name		Pin No.	I/O	Description	DC Characteristics	Comment
							VILmin=-0.3V	1.8V power domain.
							VILmax=0.6V
		PCM_IN		24	DI	PCM data input		If unused, keep it
							VIHmin=1.2V
								open.
							VIHmax=2.0V
							VOLmax=0.45V	1.8V power domain.
		PCM_OUT		25	DO	PCM data output		If unused, keep it
							VOHmin=1.35V
								open.
							VOLmax=0.45V	1.8V power domain.
								In master mode, it is
							VOHmin=1.35V
						PCM data frame		an output signal. In
							VILmin=-0.3V
		PCM_SYNC		26	IO	synchronization		slave mode, it is an
							VILmax=0.6V
						signal		input signal.
							VIHmin=1.2V
								If unused, keep it
							VIHmax=2.0V
								open.
							VOLmax=0.45V	1.8V power domain.
								In master mode, it is
							VOHmin=1.35V
								an output signal. In
							VILmin=-0.3V
		PCM_CLK		27	IO	PCM clock		slave mode, it is an
							VILmax=0.6V
								input signal.
							VIHmin=1.2V
								If unused, keep it
							VIHmax=2.0V
								open.
		I2C Interface
		Pin Name		Pin No.	I/O	Description	DC Characteristics	Comment
								External pull-up
		I2C_SCL		41	OD	I2C serial clock Used		resistor is required.
						for external codec.		1.8V only. If unused,

keep it open.

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								External pull-up
		I2C_SDA		42	OD	I2C serial dataUsed		resistor is required.
						for external codec.		1.8V only. If unused,
								keep it open.
		SD Card Interface
		Pin Name		Pin No.	I/O Description		DC Characteristics	Comment
							1.8V signaling:
							VOLmax=0.45V
							VOHmin=1.4V
							VILmin=-0.3V	SDIO signal level can
							VILmax=0.58V
								be selected according
							VIHmin=1.27V
								to SD card supported
							VIHmax=2.0V
		SDC2_				SD card SDIO bus		level, please refer to
				28	IO
		DATA3				DATA3		SD 3.0 protocol for
							3.0V signaling:
								more details.
							VOLmax=0.38V
								If unused, keep it
							VOHmin=2.01V
								open.
							VILmin=-0.3V
							VILmax=0.76V
							VIHmin=1.72V
							VIHmax=3.34V
							1.8V signaling:
							VOLmax=0.45V
							VOHmin=1.4V
							VILmin=-0.3V	SDIO signal level can
							VILmax=0.58V
								be selected according
							VIHmin=1.27V
								to SD card supported
							VIHmax=2.0V
		SDC2_				SD card SDIO bus		level, please refer to
				29	IO
		DATA2				DATA2		SD 3.0 protocol for
							3.0V signaling:
								more details.
							VOLmax=0.38V
								If unused, keep it
							VOHmin=2.01V
								open.
							VILmin=-0.3V
							VILmax=0.76V
							VIHmin=1.72V
							VIHmax=3.34V
							1.8V signaling:
							VOLmax=0.45V
		SDC2_		30	IO	SD card SDIO bus	VOHmin=1.4V
		DATA1				DATA1	VILmin=-0.3V	SDIO signal level can
							VILmax=0.58V	be selected according
							VIHmin=1.27V	to SD card supported

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							VIHmax=2.0V	level, please refer to
								SD 3.0 protocol for
							3.0V signaling:	more details.
							VOLmax=0.38V	If unused, keep it
							VOHmin=2.01V	open.
							VILmin=-0.3V
							VILmax=0.76V
							VIHmin=1.72V
							VIHmax=3.34V
							1.8V signaling:
							VOLmax=0.45V
							VOHmin=1.4V
							VILmin=-0.3V	SDIO signal level can
							VILmax=0.58V
								be selected according
							VIHmin=1.27V
								to SD card supported
							VIHmax=2.0V
	SDC2_					SD card SDIO bus		level, please refer to
			31		IO
	DATA0					DATA0		SD 3.0 protocol for
							3.0V signaling:
								more details.
							VOLmax=0.38V
								If unused, keep it
							VOHmin=2.01V
								open.
							VILmin=-0.3V
							VILmax=0.76V
							VIHmin=1.72V
							VIHmax=3.34V
							1.8V signaling:	SDIO signal level can
								be selected according
							VOLmax=0.45V
								to SD card supported
							VOHmin=1.4V
						SD card SDIO bus		level, please refer to
	SDC2_CLK		32		DO
						clock		SD 3.0 protocol for
							3.0V signaling:
								more details.
							VOLmax=0.38V
								If unused, keep it
							VOHmin=2.01V
								open.
							1.8V signaling:
							VOLmax=0.45V
							VOHmin=1.4V	SDIO signal level can
							VILmin=-0.3V	be selected according
							VILmax=0.58V	to SD card supported
	SDC2_CMD		33		IO	SD card SDIO bus	VIHmin=1.27V	level, please refer to
						command	VIHmax=2.0V	SD 3.0 protocol for
								more details.
							3.0V signaling:	If unused, keep it
							VOLmax=0.38V	open.
							VOHmin=2.01V
							VILmin=-0.3V
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						VILmax=0.76V
						VIHmin=1.72V
						VIHmax=3.34V
						VILmin=-0.3V	1.8V power domain.
		SD_INS_			SD card insertion	VILmax=0.6V
			23	DI			If unused, keep it
		DET			detect	VIHmin=1.2V
							open.
						VIHmax=2.0V
							1.8V/2.85V
					SD card SDIO bus		configurable. Cannot
		VDD_SDIO	34	PO		IOmax=50mA	be used for SD card
					pull-up power
							power. If unused,
							keep it open.
		SGMII Interface
		Pin Name	Pin No.	I/O	Description	DC Characteristics	Comment
						For 1.8V:
						VOLmax=0.45V	1.8V/2.85V power
						VOHmin=1.4V
		EPHY_RST_					domain.
			119	DO	Ethernet PHY reset
		N				For 2.85V:	If unused, keep it
							open.
						VOLmax=0.35V
						VOHmin=2.14V
						VILmin=-0.3V	1.8V power domain.
					Ethernet PHY	VILmax=0.6V
		EPHY_INT_N	120	DI			If unused, keep it
					interrupt	VIHmin=1.2V
							open.
						VIHmax=2.0V
						For 1.8V:
						VOLmax=0.45V
						VOHmin=1.4V
						VILmax=0.58V	1.8V/2.85V power
					SGMII MDIO	VIHmin=1.27V
		SGMII_					domain.
			121	IO	(Management Data
		MDATA					If unused, keep it
					Input/Output) data	For 2.85V:
							open.
						VOLmax=0.35V
						VOHmin=2.14V
						VILmax=0.71V
						VIHmin=1.78V
						For 1.8V:
						VOLmax=0.45V	1.8V/2.85V power
					SGMII MDIO	VOHmin=1.4V
		SGMII_					domain.
			122	DO	(Management Data
		MCLK					If unused, keep it
					Input/Output) clock	For 2.85V:
							open.
						VOLmax=0.35V
						VOHmin=2.14V
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									Configurable power
									source.
									1.8V/2.85V power
		USIM2_VDD		128		PO	SGMII MDIO pull-up		domain.
							power source		External pull-up for
									SGMII MDIO pins.
									If unused, keep it
									open.
									Connect with a 0.1uF
							SGMII transmission		capacitor, close to the
		SGMII_TX_M		123		AO			PHY side.
							- minus
									If unused, keep it
									open.
									Connect with a 0.1uF
							SGMII transmission		capacitor, close to the
		SGMII_TX_P		124		AO			PHY side.
							- plus
									If unused, keep it
									open.
									Connect with a 0.1uF
							SGMII receiving		capacitor, close to
		SGMII_RX_P		125		AI			EC25 module.
							- plus
									If unused, keep it
									open.
									Connect with a 0.1uF
							SGMII receiving		capacitor, close to
		SGMII_RX_M		126		AI			EC25 module.
							-minus
									If unused, keep it
									open.
		Wireless Connectivity Interfaces
		Pin Name		Pin No.		I/O Description		DC Characteristics	Comment
								VOLmax=0.45V
								VOHmin=1.35V	1.8V power domain.
		SDC1_					WLAN SDIO data	VILmin=-0.3V
				129		IO			If unused, keep it
		DATA3					bus D3	VILmax=0.6V
									open.
								VIHmin=1.2V
								VIHmax=2.0V
								VOLmax=0.45V
								VOHmin=1.35V	1.8V power domain.
		SDC1_					WLAN SDIO data	VILmin=-0.3V
				130		IO			If unused, keep it
		DATA2					bus D2	VILmax=0.6V
									open.
								VIHmin=1.2V
								VIHmax=2.0V
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								VOLmax=0.45V
								VOHmin=1.35V	1.8V power domain.
	SDC1_				WLAN SDIO data			VILmin=-0.3V
			131	IO					If unused, keep it
	DATA1				bus D1			VILmax=0.6V
									open.
								VIHmin=1.2V
								VIHmax=2.0V
								VOLmax=0.45V
								VOHmin=1.35V	1.8V power domain.
	SDC1_				WLAN SDIO data			VILmin=-0.3V
			132	IO					If unused, keep it
	DATA0				bus D0			VILmax=0.6V
									open.
								VIHmin=1.2V
								VIHmax=2.0V
					WLAN SDIO bus			VOLmax=0.45V	1.8V power domain.
	SDC1_CLK		133	DO					If unused, keep it
					clock			VOHmin=1.35V
									open.
					WLAN SDIO bus			VOLmax=0.45V	1.8V power domain.
	SDC1_CMD		134	DO					If unused, keep it
					command			VOHmin=1.35V
									open.
					External power			VOLmax=0.45V	1.8V power domain.
	PM_ENABLE		127	DO					If unused, keep it
					control			VOHmin=1.35V
									open.
					Wake	up the	host	VILmin=-0.3V	1.8V power domain.
	WAKE_ON_		135	DI	(EC25	module)	by	VILmax=0.6V	Active low.
	WIRELESS				FC20 module			VIHmin=1.2V	If unused, keep it
								VIHmax=2.0V	open.
									1.8V power domain.
					WLAN function				Active high.
								VOLmax=0.45V	Cannot be pulled up
	WLAN_EN		136	DO	control via FC20
								VOHmin=1.35V	before startup.
					module
									If unused, keep it
									open.
								VILmin=-0.3V	1.8V power domain.
									Cannot be pulled up
	COEX_UART				LTE/WLAN&BT			VILmax=0.6V
			137	DI					before startup.
	_RX				coexistence signal			VIHmin=1.2V	If unused, keep it
								VIHmax=2.0V
									open.
									1.8V power domain.
	COEX_UART				LTE/WLAN&BT			VOLmax=0.45V	Cannot be pulled up
			138	DO					before startup.
	_TX				coexistence signal			VOHmin=1.35V	If unused, keep it
									open.
	WLAN_SLP_		118	DO	WLAN sleep clock				If unused, keep it
	CLK								open.

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								VILmin=-0.3V	1.8V power domain.
							BT UART request to	VILmax=0.6V
		BT_RTS*		37		DI			If unused, keep it
							send	VIHmin=1.2V
									open.
								VIHmax=2.0V
							BT UART transmit	VOLmax=0.45V	1.8V power domain.
		BT_TXD*		38		DO			If unused, keep it
							data	VOHmin=1.35V
									open.
								VILmin=-0.3V	1.8V power domain.
							BT UART receive	VILmax=0.6V
		BT_RXD*		39		DI			If unused, keep it
							data	VIHmin=1.2V
									open.
								VIHmax=2.0V
									1.8V power domain.
							BT UART clear to	VOLmax=0.45V	Cannot be pulled up
		BT_CTS*		40		DO			before startup.
							send	VOHmin=1.35V
									If unused, keep it
									open.
							BT function control	VOLmax=0.45V	1.8V power domain.
		BT_EN*		139		DO			If unused, keep it
							via the BT module	VOHmin=1.35V
									open.
		RF Interface
		Pin Name		Pin No.		I/O	Description	DC Characteristics	Comment
							Diversity antenna		50Ω impedance
		ANT_DIV		35		AI			If unused, keep it
							pad
									open.
		ANT_MAIN		49		IO	Main antenna pad		50Ω impedance
									50Ω impedance
		ANT_GNSS		47		AI	GNSS antenna pad		If unused, keep it
									open.
		GPIO Pins
		Pin Name		Pin No.		I/O	Description	DC Characteristics	Comment

VILmin=-0.3V

WAKEUP_IN 1 DI Sleep mode control 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.

			Airplane mode	VILmin=-0.3V	1.8V power domain.
	W_DISABLE# 4	DI		VILmax=0.6V	Pull-up by default.
			control
				VIHmin=1.2V	At low voltage level,
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							VIHmax=2.0V	module can enter into
								airplane mode.
								If unused, keep it
								open.
						Application	VILmin=-0.3V	1.8V power domain.
							VILmax=0.6V
		AP_READY		2	DI	processor sleep		If unused, keep it
							VIHmin=1.2V
						state detection		open.
							VIHmax=2.0V
		USB_BOOT Interface
		Pin Name		Pin No.	I/O	Description	DC Characteristics	Comment

			Force the module to	VILmin=-0.3V
	USB_BOOT 115	DI	enter into	VILmax=0.6V
			emergency	VIHmin=1.2V
			download mode	VIHmax=2.0V

1.8V power domain. Cannot be pulled up before startup.

It is recommended to reserve test point.

RESERVED Pins

	Pin Name	Pin No. I/O	Description	DC Characteristics Comment
		3, 18, 43,
		55, 73~84,		Keep these pins
	RESERVED	113, 114,	Reserved
				unconnected.
		116, 117,
		140-144.

NOTES

1.“*” means under development.

2.Pads 24~27 are multiplexing pins used for audio design on the EC25 module and BT function on the BT module.

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3.4. 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

Talk/Data

Software is active. The module has registered on the network, and it is ready to send and receive data.

Network connection is ongoing. In this mode, the power consumption is decided by network setting and data transfer rate.

Minimum

Functionality

Mode

Airplane Mode

Sleep Mode

Power Down

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.

AT+CFUN command or W_DISABLE# pin can set the module to airplane mode. In this case, RF function will be invalid.

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.

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.

3.5. Power Saving

3.5.1. Sleep Mode

EC25 is able to reduce its current consumption to a minimum value during the sleep mode. The following section describes power saving procedures of EC25 module.

3.5.1.1. 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.

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The following figure shows the connection between the module and the host.

Figure 3: Sleep Mode Application via UART

Driving the host DTR to low level will wake up the module.

When EC25 has a URC to report, RI signal will wake up the host. Please refer to Chapter 3.17 for details about RI behaviors.

AP_READY will detect the sleep state of the host (can be configured to high level or low level detection). Please refer to AT+QCFG="apready"* command for details.

NOTE

“*” means under development.

3.5.1.2. USB Application with USB Remote Wakeup Function

If the host supports USB suspend/resume and remote wakeup function, the following three preconditions must be met to let the module enter into the sleep mode.

Execute AT+QSCLK=1 command to enable sleep mode.

Ensure the DTR is held at high level or keep it open.

The host’s USB bus, which is connected with the module’s USB interface, enters into suspended state.

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The following figure shows the connection between the module and the host.

Figure 4: Sleep Mode Application with USB Remote Wakeup

Sending data to EC25 through USB will wake up the module.

When EC25 has a URC to report, the module will send remote wake-up signals via USB bus so as to wake up the host.

3.5.1.3. USB Application with USB Suspend/Resume and RI Function

If the host supports USB suspend/resume, but does not support remote wake-up function, the RI signal is needed to wake up the host.

There are three preconditions to let the module enter into the sleep mode.

Execute AT+QSCLK=1 command to enable the sleep mode.

Ensure the DTR is held at high level or keep it open.

The host’s USB bus, which is connected with the module’s USB interface, enters into suspended state.

The following figure shows the connection between the module and the host.

Figure 5: Sleep Mode Application with RI

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Sending data to EC25 through USB will wake up the module.

When EC25 has a URC to report, RI signal will wake up the host.

3.5.1.4. USB Application without USB Suspend Function

If the host does not support USB suspend function, USB_VBUS should be disconnected via an additional control circuit to let the module enter into sleep mode.

Execute AT+QSCLK=1 command to enable sleep mode.

Ensure the DTR is held at high level or keep it open.

Disconnect USB_VBUS.

The following figure shows the connection between the module and the host.

Figure 6: Sleep Mode Application without Suspend Function

Switching on the power switch to supply power to USB_VBUS will wake up the module.

NOTE

Please pay attention to the level match shown in dotted line between the module and the host. For more details about EC25 power management application, please refer to document [1].

3.5.2. Airplane Mode

When the module enters into airplane mode, the RF function does not work, and all AT commands correlative with RF function will be inaccessible. This mode can be set via the following ways.

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Hardware:

The W_DISABLE# pin is pulled up by default; driving it to low level will let the module enter into airplane mode.

Software:

AT+CFUN command provides the choice of the functionality level through setting <fun> into 0, 1 or 4.

AT+CFUN=0: Minimum functionality mode. Both (U)SIM and RF functions are disabled.

AT+CFUN=1: Full functionality mode (by default).

AT+CFUN=4: Airplane mode. RF function is disabled.

NOTES

1.The W_DISABLE# control function is disabled in firmware by default. It can be enabled by AT+QCFG="airplanecontrol" command, and this command is under development.

2.The execution of AT+CFUN command will not affect GNSS function.

3.6. Power Supply

3.6.1. Power Supply Pins

EC25 provides four VBAT pins to connect with the external power supply, and there are two separate voltage domains for VBAT.

Two VBAT_RF pins for module’s RF part

Two VBAT_BB pins for module’s baseband part

The following table shows the details of VBAT pins and ground pins.

Table 6: VBAT and GND Pins

	Pin Name	Pin No.		Description	Min.		Typ.	Max.		Unit
	VBAT_RF	57, 58		Power supply for module’s RF	3.3		3.8	4.3		V
				part
	VBAT_BB	59, 60		Power supply for module’s	3.3		3.8	4.3		V
				baseband part
		8, 9, 19, 22, 36,
	GND	46, 48, 50~54,		Ground	-		0	-		V
		56, 72, 85~112

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3.6.2. Decrease Voltage Drop

The power supply range of the module is from 3.3V to 4.3V. Please make sure that the input voltage will never drop below 3.3V. The following figure shows the voltage drop during burst transmission in 2G network. The voltage drop will be less in 3G and 4G networks.

Figure 7: Power Supply Limits during Burst Transmission

To decrease voltage drop, a bypass capacitor of about 100µF with low ESR (ESR=0.7Ω) should be used, and a multi-layer ceramic chip (MLCC) capacitor array should also be reserved due to its ultra-low ESR. It is recommended to use three ceramic capacitors (100nF, 33pF, 10pF) for composing the MLCC array, and place these capacitors close to VBAT_BB/VBAT_RF pins. The main power supply from an external application has to be a single voltage source and can be expanded to two sub paths with star structure. The width of VBAT_BB trace should be no less than 1mm; and the width of VBAT_RF trace should be no less than 2mm. In principle, the longer the VBAT trace is, the wider it will be.

In addition, in order to get a stable power source, it is suggested that a zener diode whose reverse zener voltage is 5.1V and dissipation power is more than 0.5W should be used. The following figure shows the star structure of the power supply.

Figure 8: Star Structure of the Power Supply

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3.6.3. Reference Design for Power Supply

Power design for the module is very important, as the performance of the module largely depends on the power source. The power supply should be able to provide sufficient current up to 2A at least. If the voltage drop between the input and output is not too high, it is suggested that an LDO should be used to supply power for the module. If there is a big voltage difference between the input source and the desired output (VBAT), a buck converter is preferred to be used as the power supply.

The following figure shows a reference design for +5V input power source. The typical output of the power supplyis about 3.8V and the maximum load current is 3A.

Figure 9: Reference Circuit of Power Supply

NOTE

In order to avoid damaging internal flash, please do not switch off the power supply when the module works normally. Only after the module is shutdown by PWRKEY or AT command, then the power supply can be cut off.

3.6.4. Monitor the Power Supply

AT+CBC command can be used to monitor the VBAT_BB voltage value. For more details, please refer to document [2].

3.7. Turn on and off Scenarios

3.7.1. Turn on Module Using the PWRKEY

The following table shows the pin definition of PWRKEY.

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Table 7: Pin Definition of PWRKEY

	Pin Name	Pin No.		I/O	Description		Comment
	PWRKEY	21		DI	Turn on/off the module		The output voltage is 0.8V because of
							the diode drop in the Qualcomm chipset.

When EC25 is in power down mode, it can be turned on to normal mode by driving the PWRKEY pin to a low level for at least 500ms. It is recommended to use an open drain/collector driver to control the PWRKEY. After STATUS pin (require external pull-up) outputting a low level, PWRKEY pin can be released. A simple reference circuit is illustrated in the following figure.

PWRKEY

≥ 500ms

4.7K

10nF Turn on pulse

47K

Figure 10: Turn on the Module by Using Driving Circuit

The other way to control the PWRKEY is using a button directly. When pressing the key, electrostatic strike may generate from finger. Therefore, a TVS component is indispensable to be placed nearby the button for ESD protection. A reference circuit is shown in the following figure.

Figure 11: Turn on the Module by Using Button

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The turn on scenario is illustrated in the following figure.

Figure 12: Timing of Turning on Module

NOTE

Please make sure that VBAT is stable before pulling down PWRKEY pin. The time between them should be no no less than 30ms.

3.7.2. Turn off Module

The following procedures can be used to turn off the module:

Normal power down procedure: Turn off the module using the PWRKEY pin.

Normal power down procedure: Turn off the module using AT+QPOWD command.

3.7.2.1. Turn off Module Using the PWRKEY Pin

Driving the PWRKEY pin to a low level voltage for at least 650ms, the module will execute power-down procedure after the PWRKEY is released. The power-down scenario is illustrated in the following figure.

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Figure 13: Timing of Turning off Module

3.7.2.2. Turn off Module Using AT Command

It is also a safe way to use AT+QPOWD command to turn off the module, which is similar to turning off the module via PWRKEY pin.

Please refer to document [2] for details about AT+QPOWD command.

NOTES

1.Inorder to avoid damaging internal flash, please do not switch off the power supply when the module works normally. Only after the module is shut down by PWRKEY or AT command, then the power supply can be cut off.

2.When turn off module with AT command, please keep PWRKEY at high level after the execution of power-off command. Otherwise the module will be turned on again after successfully turn-off.

3.8. Reset the Module

The RESET_N pin can be used to reset the module. The module can be reset by driving RESET_N to a low level voltage for time between 150ms and 460ms.

	Table 8: RESET_N Pin Description
	Pin Name	Pin No.	I/O	Description	Comment
	RESET_N	20	DI	Reset the module	1.8V power domain
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The recommended circuit is similar to the PWRKEY control circuit. An open drain/collector driver or button can be used to control the RESET_N.

Figure 14: Reference Circuit of RESET_N by Using Driving Circuit

Figure 15: Reference Circuit of RESET_N by Using Button

The reset scenario is illustrated inthe following figure.

Figure 16: Timing of Resetting Module

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NOTES

1.Use RESET_N only when turning off the module by AT+QPOWD command and PWRKEY pin failed.

2.Ensure that there is no large capacitance on PWRKEY and RESET_N pins.

3.9. (U)SIM Interface

The(U)SIM interface circuitry meets ETSI and IMT-2000 requirements. Both 1.8V and 3.0V (U)SIM cards are supported.

Table 9: Pin Definition of the (U)SIM Interface

	Pin Name	Pin No.		I/O		Description		Comment
	USIM_VDD	14	PO		Power supply for (U)SIM card			Either 1.8V or 3.0V is supported
								by the module automatically.
	USIM_DATA	15	IO		Data signal of (U)SIM card
	USIM_CLK	16		DO		Clock signal of (U)SIM card
	USIM_RST	17		DO		Reset signal of (U)SIM card
	USIM_	13		DI		(U)SIM card insertion detection
	PRESENCE
	USIM_GND	10			Specified ground for (U)SIM card

EC25 supports (U)SIM card hot-plug via the USIM_PRESENCE pin. The function supports low level and high level detections, and it is disabled by default. Please refer to document [2] for more details about

AT+QSIMDET command.

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The following figure shows a reference design for (U)SIM interface with an 8-pin (U)SIM card connector.

Figure 17: Reference Circuit of (U)SIM Interface with an 8-Pin (U)SIM Card Connector

If (U)SIM card detection function is not needed, please keep USIM_PRESENCE unconnected. A reference circuit for (U)SIM interface with a 6-pin (U)SIM card connector is illustrated in the following figure.

Figure 18: Reference Circuit of (U)SIM Interface with a 6-Pin (U)SIM Card Connector

In order to enhance the reliability and availability of the (U)SIM card in customers’ applications, please follow the criteria below in (U)SIM circuit design:

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Keep placement of (U)SIM card connector to the module as close as possible. Keep the trace length as less than 200mm as possible.

Keep (U)SIM card signals away from RF and VBAT traces.

Assure the ground between the module and the (U)SIM card connector short and wide. Keep the trace width of ground and USIM_VDD no less than 0.5mm to maintain the same electric potential. Make sure the bypass capacitor between USIM_VDD and USIM_GND less than 1uF, and place it as close to (U)SIM card connector as possible. If the ground is complete on customers’ PCB, USIM_GND can be connected to PCB ground directly.

To avoid cross-talk between USIM_DATA and USIM_CLK, keep them away from each other and shield them with surrounded ground.

In order to offer good ESD protection, it is recommended to add a TVS diode array whose parasitic capacitance should not be more than 15pF. The 0Ω resistors should be added in series between the module and the (U)SIM card to facilitate debugging. The 33pF capacitors are used for filtering interference of EGSM900. Please note that the (U)SIM peripheral circuit should be close to the (U)SIM card connector.

The pull-up resistor on USIM_DATA line can improve anti-jamming capability when long layout trace and sensitive occasion are applied, and it should be placed close to the (U)SIM card connector.

3.10. USB Interface

EC25 contains one integrated Universal Serial Bus (USB) interface which complies with the USB 2.0 specification and supports high-speed (480Mbps) and full-speed (12Mbps) modes. The USB interface is used for AT command communication, data transmission, GNSS NMEA sentences output, software debugging, firmware upgrade and voice over USB*. The following table shows the pin definition of USB interface.

Table 10: Pin Description of USB Interface

	Pin Name	Pin No.		I/O	Description		Comment
	USB_DP	69		IO	USB differential data bus (+)		Require differential
							impedance of 90Ω
	USB_DM	70		IO	USB differential data bus (-)		Require differential
							impedance of 90Ω
	USB_VBUS	71	PI		USB connection detection		Typical 5.0V
	GND	72			Ground

For more details about the USB 2.0 specifications, please visit http://www.usb.org/home.

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The USB interface is recommended to be reserved for firmware upgrade in customers’ designs. The following figure shows a reference circuit of USB interface.

Figure 19: Reference Circuit of USB Application

A common mode choke L1 is recommended to be added in series between the module and customer’s MCU in order to suppress EMI spurious transmission. Meanwhile, the 0Ω resistors (R3 and R4) should be added in series between the module and the test points so as to facilitate debugging, and the resistors are not mounted by default. In order to ensure the integrity of USB data line signal, L1/R3/R4 components must be placed close to the module, and also these resistors should be placed close to each other. The extra stubs of trace must be as short as possible.

The following principles should be complied with when design the USB interface, so as to meet USB 2.0 specification.

It is important to route the USB signal traces as differential pairs with total grounding. The impedance of USB differential trace is 90Ω.

Do not route signal traces under crystals, oscillators, magnetic devices and RF signal traces. It is important to route the USB differential traces in inner-layer with ground shielding on not only upper and lower layers but also right and left sides.

Pay attention to the influence of junction capacitance of ESD protection components on USB data lines. Typically, the capacitance value should be less than 2pF.

Keep the ESD protection components to the USB connector as close as possible.

NOTES

1.EC25 module can only be used as a slave device.

2.“*” means under development.

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3.11. UART Interfaces

The module provides two UART interfaces: the main UART interface and the debug UART interface. The following shows their features.

The main UART interface supports 4800bps, 9600bps, 19200bps, 38400bps, 57600bps, 115200bps, 230400bps, 460800bps and 921600bps baud rates, and the default is 115200bps. This interface is used for data transmission and AT command communication.

The debug UART interface supports 115200bps baud rate. It is used for Linux console and log output.

The following tables show the pin definition of the UART interfaces.

Table 11: Pin Definition of Main UART Interface

Pin Name	Pin No.	I/O	Description	Comment
RI	62	DO	Ring indicator
DCD	63	DO	Data carrier detection
CTS	64	DO	Clear to send
RTS	65	DI	Request to send	1.8V power domain
DTR	66	DI	Data terminal ready
TXD	67	DO	Transmit data
RXD	68	DI	Receive data

Table 12: Pin Definition of Debug UART Interface

	Pin Name	Pin No.	I/O	Description			Comment
	DBG_TXD	12	DO	Transmit data			1.8V power domain
	DBG_RXD	11	DI	Receive data

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