Table Index ............................................................................................................................................... 6
Figure Index .............................................................................................................................................. 8
FIGURE 46: TAPE AND REEL SPECIFICATIONS ........................................................................................... 83
EC25_Hardware_DesignConfidential / Released 9 / 90
LTE Module Series
EC25Hardware Design
1Introduction
This document defines the EC25module and describes its air interface and hardware interface which are
connected with your application.
This document can help you quickly understand module interface specifications, electrical and
mechanical details, as well as other related information of EC25 module. Associated with application note
and user guide, you can use EC25 module to design and set up mobile applications easily.
EC25_Hardware_DesignConfidential / Released 10 / 90
LTE Module Series
EC25Hardware Design
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, Quectelassumes no liability for the
customer’s failure to comply with these precautions.
Full attention must be given to driving at all times in order to reduce the risk of an
accident. Using a mobile while driving (even with a handsfree kit) causes
distraction and can lead to an accident. You must comply with laws and regulations
restricting the use of wireless devices while driving.
Switch off the cellular terminal or mobile before boarding an aircraft. Make sure it is
switched off. The operation of wireless appliances in an aircraft is forbidden, so as
to prevent interference with communication systems. Consult the airline staff about
the use of wireless devices on boarding the aircraft, if your device offers an
Airplane Mode which must be enabled prior to boarding an aircraft.
Switch off your wireless device when in hospitals,clinics or other health care
facilities. These requests are desinged to prevent possible interference with
sensitive medical equipment.
Cellular terminals or mobiles operatingover 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.
EC25_Hardware_DesignConfidential / Released 11 / 90
LTE Module Series
EC25Hardware Design
2Product Concept
2.1. General Description
EC25 is a series of LTE-FDD/LTE-TDD/WCDMA/GSM wireless communication module with receive
diversity, which provides data connectivity on LTE-FDD,LTE-TDD,DC-HSPA+, HSPA+, HSDPA, HSUPA,
WCDMA,EDGE andGPRSnetworks. It also provides GNSS
application.EC25 contains fivevariants:EC25-E, EC25-A, EC25-V, EC25-Jand EC25-AU. You can choose
a dedicated type based on the region or operator. The following table shows the frequency bands of EC25
series module.
1)
and voice functionality2) for your specific
Table 1: Frequency Bands of EC25 Series Module
Modules2) LTE Bands 3G Bands GSM
EC25-E
EC25-A
EC25-V
EC25-J
EC25-AU3)
NOTES
FDD:B1/B3/B5/B7/B8/
B20
TDD: B38/B40/B41
FDD: B2/B4/B12
FDD: B4/B13 Not supportedNot supportedSupported
FDD: B1/B3/B8/B18/B19/
B26
TDD: B41
FDD: B1/B2/B3/B4/B5/B7/
B8/B28
TDD: B40
WCDMA:
B1/B5/B8
WCDMA:
B2/B4/B5
WCDMA:
B1/B6/B8/
B19
WCDMA:
B1/B2/B5/B8
900/1800 Supported
Not supportedSupported
Not supportedSupported
850/900/
1800/1900
Rxdiversity
Supported
GNSS1)
GPS,
GLONASS,
BeiDou/
Compass,
Galileo,
QZSS
1)
1.
GNSS function is optional.
2)
2.
3.
EC25_Hardware_DesignConfidential / Released 12 / 90
EC25 series module (EC25-E/EC25-A/EC25-V/EC25-J/EC25-AU) includes Data-only and
Telematics versions. Data-only version does not support voice function, while Telematics version
supports it.
3)
B2 band on EC25-AU module does not support Rx-diversity.
LTE Module Series
EC25Hardware Design
With a tiny profile of 32.0mm ×29.0mm ×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 in applications through its 144-pin pads, including
80 LCC signal pads and 64 other pads.
2.2. Key Features
The following table describes the detailed features of EC25 module.
Table 2: Key Features of EC25 Module
Feature Details
Power Supply Supply voltage: 3.3V~4.3VTypical supply voltage: 3.8V
Class 4 (33dBm±2dB) for GSM900
Class 1 (30dBm±2dB) for DCS1800
Class E2 (27dBm±3dB) for GSM900 8-PSK
Transmitting Power
Class E2 (26dBm±3dB) for DCS1800 8-PSK
Class 3 (23dBm+1/-3dB) for WCDMA bands
Class 3 (23dBm+1/-3dB) for LTE-FDD band5
Class 3 (22.5dBm+1/-3dB) for LTE-FDD band7
Class 3 (23dBm+1/-3dB) for LTE-TDD bands
Support up to non-CA CAT4
Support 1.4 to 20MHz RF bandwidth
LTE Features
Support MIMO in DL direction
FDD: Max 50Mbps (UL), 150Mbps (DL)
TDD: Max 35Mbps (UL), 130Mbps (DL)
Support 3GPP R8 DC-HSPA+
WCDMA Features
Support 16-QAM, 64-QAM and QPSKmodulation
3GPP R6 CAT6 HSUPA: Max 5.76Mbps (UL)
3GPP R8 CAT24 DC-HSPA+: Max 42Mbps (DL)
R99:
CSD: 9.6kbps, 14.4kbps
GPRS:
GSMFeatures
Support GPRS multi-slot class 12 (12 by default)
Coding scheme: CS-1, CS-2, CS-3 and CS-4
Maximum of four Rx time slots per frame
EDGE:
Support EDGE multi-slot class 12 (12 by default)
EC25_Hardware_DesignConfidential / Released 13 / 90
EC25Hardware Design
Support GMSK and 8-PSK for different MCS (Modulation and Coding
Support the protocols PAP (Password Authentication Protocol) and CHAP
(Challenge Handshake Authentication Protocol) usually used for PPP
connections
Text and PDU mode
SMS
Point to point MO and MT
SMS cell broadcast
SMS storage: ME by default
USIM 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
LTE Module Series
PCM Interface
USB Interface
UART Interface
Used for audio function with external codec
Support 8-bit A-law*, μ-law*and 16-bit linear data formats
Support long frame synchronization and short frame synchronization
Support master and slave modes, but must be the master in long frame
synchronization
Compliant with USB 2.0 specification (slave only);the data transfer rate can
reach up to 480Mbps
Used for AT command communication, data transmission, GNSS NMEA
output, software debugging, firmware upgrade and voiceover USB*
Support USB drivers for: 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
Main UART:
Used for AT command communication and data transmission
Baud rate reach up to 3000000bps, 115200bps by default
Support RTS and CTS hardware flow control
Debug UART:
Used for Linux console, log output
115200bps baud rate
SGMII Interface Support 10/100/1000Mbps Ethernet connectivity
Wireless Connectivity
Interfaces
Support a low-power SDIO 3.0 interface for WLAN and UART/PCM
interface for Bluetooth*
EC25_Hardware_DesignConfidential / Released 14 / 90
EC25Hardware Design
Rx-diversitySupport LTE/WCDMA Rx-diversity
LTE Module Series
GNSS Features
AT Commands
Network Indication
Antenna Interface
Physical Characteristics
Temperature Range
Gen8CLite of Qualcomm
Protocol: NMEA 0183
Compliant with 3GPP TS 27.007, 27.005 and Quectel enhanced AT
commands
Two pins including NET_MODE and NET_STATUS to indicate network
connectivity status
Including main antenna interface (ANT_MAIN), Rx-diversityantenna
interface (ANT_DIV) and GNSS antenna interface (ANT_GNSS)
Size: 32.0±0.15×29.0±0.15×2.4±0.2mm
Weight: approx. 4.9g
Operation temperature range: -35°C ~ +75°C
Extended temperature range: -40°C ~ +85°C
1)
2)
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
P
might reduce in their value and exceed the specified tolerances. When the temperature returns to
out
the normal operating temperature levels, the module will meet 3GPP compliant again.
3. “*” means under development.
2.3. Functional Diagram
The following figure shows a block diagram of EC25 and illustrates the major functional parts.
EC25_Hardware_DesignConfidential / Released 15 / 90
EC25Hardware Design
Power management
Baseband
DDR+NAND flash
Radio frequency
Peripheral interfaces
LTE Module Series
ANT_MAINANT_DIVANT_GNSS
VBAT_RF
VBAT_BB
PWRKEY
RESET_N
ADCs
STATUS
APT
PMIC
Tx
Control
19.2M
PA
XO
Switch
Duplex
PRxDRx
SAW
LNA
Transceiver
IQControl
Baseband
Switch
SAW
NAND
DDR2
SDRAM
VDD_EXT
USB
USIM
PCM
SGMII
WLAN
I2C
UART
GPIOs
BT
Figure 1: Functional Diagram
2.4. Evaluation Board
In order to help youto develop applications with EC25, Quectel supplies an evaluation board (EVB), USB
data cable, earphone, antenna and other peripherals to control or test the module.
EC25_Hardware_DesignConfidential / Released 16 / 90
LTE Module Series
EC25Hardware Design
3Application Interface
3.1. General Description
EC25 is equipped with 80-pin SMT pads plus 64-pin ground pads and reserved pads that can
beconnected to cellular application platform. Sub-interfaces included in these pads are described in detail
in the following chapters:
Power supply
USIM interface
USB interface
UART interfaces
PCM interface
ADC interface
Status indication
SGMII interface
Wireless connectivityinterfaces
USB_BOOT interface
EC25_Hardware_DesignConfidential / Released 17 / 90
EC25Hardware Design
3.2. Pin Assignment
The following figure shows the pin assignment of EC25 module.
LTE Module Series
WAKEUP_IN
AP_READY
RESERVED
W_DISABLE#
NET_MODE
NET_STATUS
VDD_EXT
RESERVED
RESERVED
GND
GND
USIM_GND
DBG_RXD
DBG_TXD
USIM_PRESENCE
USIM_VDD
USIM_DATA
USIM_CLK
USIM_RST
RESERVED
1)
1
2
3
4
1)
5
6
7
141
142
8
9
10
11
12
13
129
130
131
132
133
134
135
136
137
138
117
118
119
120
121
122
123
124
125
126
108
109
110
111
103
104
105
106
99
100
82
83
84
101
79
80
81
76
77
78
95
96
97
73
74
75
90
91
92
93
85
86
87
88
14
139
15
16
17
140
127
128
112
107
102
98
94
89
18
54
53
52
51
50
49
48
144
143
47
46
45
44
43
42
41
40
39
38
37
GND
GND
GND
GND
GND
ANT_MAIN
GND
RESERVED
RESERVED
ANT_GNSS
GND
ADC0
ADC1
RESERVED
I2C_SDA
I2C_SCL
BT_CTS
BT_RXD
BT_TXD
BT_RTS
GND Pins
WLAN PinsBluetooth Pins
Signal PinsRESERVED Pins
Power Pins
SGMII Pins
Figure 2: Pin Assignment (Top View)
NOTES
1. 1)meansthat these pins cannot be pulled up before startup.
2)
2.
PWRKEY output voltage is 0.8V because of the diode drop in the Qualcomm chipset.
3. Pads 119~126 are SGMII function pins.
4. Pads 37~40, 118, 127 and 129~139 are wireless connectivity interfaces, among which pads 127 and
129~138 are WLAN function pins, and others are Bluetooth (BT) function pins. BT function is under
development.
EC25_Hardware_DesignConfidential / Released 18 / 90
LTE Module Series
EC25Hardware Design
5. Pads 24~27 are multiplexing pins used for audio design on EC25 module and BT function on FC20
module.
6. Keep all RESERVEDpins and unused pins unconnected.
7. GND pads 85~112 should be connected to ground in the design, and RESERVED pads 73~84should
not be designed in schematic and PCB decal.
※
8. “
”means these interface functions are only supported on Telematics version.
3.3. Pin Description
The following tables show the pin definition of 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
VBAT_BB 59,60 PI
VBAT_RF 57,58 PI
Power supply for
module baseband
part
Power supply for
module RF part
Vmax=4.3V
Vmin=3.3V
Vnorm=3.8V
Vmax=4.3V
Vmin=3.3V
Vnorm=3.8V
It must be able to
provide sufficient
current up to 0.8A.
It must be able to
provide sufficient
current up to 1.8A in a
EC25_Hardware_DesignConfidential / Released 19 / 90
LTE Module Series
EC25Hardware Design
bursttransmission.
Power supply for
external GPIO’s pull up
circuits.
VDD_EXT 7 PO
Provide 1.8V for
external circuit
Vnorm=1.8V
I
max=50mA
O
8,9,19,22,3
GND
6,46,48,50
~54,56,72,
Ground
85~112
Turn on/off
Pin Name Pin No. I/O Description DC Characteristics Comment
The output voltage is
0.8V because of the
diode drop in the
Qualcomm chipset.
PWRKEY 21 DI
Turnon/off the
module
RESET_N 20 DI Reset the module
V
max=2.1V
IH
V
min=1.3V
IH
V
max=0.5V
IL
max=2.1V
V
IH
V
min=1.3V
IH
V
max=0.5V
IL
Status Indication
Pin Name Pin No. I/O Description DC Characteristics Comment
STATUS 61 OD
Indicate the module
operating status
The drive current
should be less than
0.9mA.
Require external
pull-up. If unused,
keep it open.
1.8V power domain.
Cannot be pulled up
before startup.
If unused, keep it
NET_MODE 5 DO
Indicate the module
network registration
mode
V
min=1.35V
OH
V
max=0.45V
OL
open.
NET_
STATUS
Indicate the module
6 DO
network activity
status
V
min=1.35V
OH
V
max=0.45V
OL
1.8V power domain.
If unused, keep it
open.
USB Interface
Pin Name Pin No. I/O Description DC Characteristics Comment
Vmax=5.25V
USB_VBUS 71 PI USB detection
Vmin=3.0V
Vnorm=5.0V
USB_DP 69 IO
USB differential data
bus
Compliant with USB
2.0 standard
specification.
EC25_Hardware_DesignConfidential / Released 20 / 90
Require differential
impedance of 90ohm.
LTE Module Series
EC25Hardware Design
USB_DM 70 IO
USB differential data
bus
Compliant with USB
2.0 standard
specification.
Require differential
impedance of 90ohm.
USIM Interface
Pin Name Pin No. I/O Description DC Characteristics Comment
USIM_GND 10
Specified ground for
USIM card
For 1.8V USIM:
Vmax=1.9V
USIM_VDD 14 PO
Power supply for
USIM card
Vmin=1.7V
For 3.0V USIM:
Vmax=3.05V
Either 1.8V or 3.0V is
supported by the
module automatically.
Vmin=2.7V
I
max=50mA
O
For 1.8V USIM:
V
max=0.6V
IL
V
min=1.2V
IH
V
max=0.45V
OL
V
min=1.35V
OH
For 3.0V USIM:
V
max=1.0V
IL
V
min=1.95V
IH
V
max=0.45V
OL
V
min=2.55V
OH
USIM_DATA 15 IO
Data signal of USIM
card
For 1.8V USIM:
V
max=0.45V
OL
V
min=1.35V
OH
For 3.0V USIM:
V
max=0.45V
OL
V
min=2.55V
OH
USIM_CLK 16 DO
Clock signal of USIM
card
For 1.8V USIM:
V
max=0.45V
OL
V
min=1.35V
OH
For 3.0V USIM:
V
max=0.45V
OL
V
min=2.55V
OH
V
min=-0.3V
IL
V
max=0.6V
IL
1.8V power domain.
If unused, keep it
USIM_RST 17 DO
USIM_
PRESENCE
13 DI
Reset signal of
USIM card
USIM card insertion
detection
EC25_Hardware_DesignConfidential / Released 21 / 90
LTE Module Series
EC25Hardware Design
VIHmin=1.2V
open.
VIHmax=2.0V
UART Interface
Pin Name Pin No. I/O Description DC Characteristics Comment
V
RI 62 DO Ring indicator
DCD 63 DO
Data carrier
detection
CTS 64 DO Clear to send
RTS 65 DI Request to send
OL
V
OH
V
OL
V
OH
V
OL
V
OH
V
IL
V
IL
V
IH
V
IH
max=0.45V
min=1.35V
max=0.45V
min=1.35V
max=0.45V
min=1.35V
min=-0.3V
max=0.6V
min=1.2V
max=2.0V
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
Data terminal
DTR 66 DI
ready,sleep mode
control
V
min=-0.3V
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
Pull-up by default.
Low level wakes up
the module.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
TXD 67 DO Transmit data
RXD 68 DI Receive data
V
max=0.45V
OL
V
min=1.35V
OH
V
min=-0.3V
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
Debug UART Interface
Pin Name Pin No. I/O Description DC Characteristics Comment
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
DBG_TXD 12 DO Transmit data
DBG_RXD 11 DI Receive data
V
max=0.45V
OL
V
min=1.35V
OH
V
min=-0.3V
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
EC25_Hardware_DesignConfidential / Released 22 / 90
LTE Module Series
EC25Hardware Design
ADC Interface
Pin Name Pin No. I/O Description DC Characteristics Comment
General purpose
ADC0 45 AI
analog to digital
converter
General purpose
ADC1 44 AI
analog to digital
converter
Voltage range:
0.3V to VBAT_BB
Voltage range:
0.3V to VBAT_BB
If unused, keep it
open.
If unused, keep it
open.
PCM Interface
Pin Name Pin No. I/O Description DC Characteristics Comment
V
min=-0.3V
PCM_IN 24 DI PCM data input
PCM_OUT 25 DO PCM data output
PCM data frame
PCM_SYNC 26 IO
synchronization
signal
PCM_CLK 27 IO PCM clock
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
V
max=0.45V
OL
V
min=1.35V
OH
VOLmax=0.45V
V
min=1.35V
OH
V
min=-0.3V
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
V
max=0.45V
OL
V
min=1.35V
OH
V
min=-0.3V
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
In master mode, it is
an output signal. In
slave mode, it is an
input signal.
If unused, keep it
open.
1.8V power domain.
In master mode, it is
an output signal. In
slave mode, it is an
input signal.
If unused, keep it
open.
I2C Interface
Pin Name Pin No. I/O Description DC Characteristics Comment
I2C serial clock
I2C_SCL 41 OD
Used for external
codec.
External pull-up
resistor is required.
1.8V only. If unused,
keep it open.
External pull-up
I2C_SDA 42 OD
I2C serial dataUsed
for external codec.
resistor is required.
1.8V only. If unused,
keep it open.
EC25_Hardware_DesignConfidential / Released 23 / 90
LTE Module Series
EC25Hardware Design
SGMII Interface
Pin Name Pin No. I/O Description DC Characteristics Comment
For 1.8V:
V
max=0.45V
EPHY_RST_
N
119 DO Ethernet PHY reset
EPHY_INT_N 120 DI
Ethernet PHY
interrupt
OL
VOHmin=1.4V
For 2.85V:
V
max=0.35V
OL
V
min=2.14V
OH
V
min=-0.3V
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
1.8V/2.85V power
domain.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
For 1.8V:
V
max=0.45V
OL
V
min=1.4V
OH
V
max=0.58V
SGMII_
MDATA
SGMII MDIO
121 IO
(Management Data
Input/Output) data
IL
V
min=1.27V
IH
For 2.85V:
V
max=0.35V
OL
V
min=2.14V
OH
V
max=0.71V
IL
V
min=1.78V
IH
1.8V/2.85V power
domain.
If unused, keep it
open.
For 1.8V:
V
max=0.45V
SGMII_
MCLK
SGMII MDIO
122 DO
(Management Data
Input/Output) clock
OL
V
min=1.4V
OH
For2.85V:
V
max=0.35V
OL
V
min=2.14V
OH
1.8V/2.85V power
domain.
If unused, keep it
open.
Configurable power
source.
1.8V/2.85V power
USIM2_VDD 128 PO
SGMII MDIO pull-up
power source
domain.
External pull-up for
SGMII MDIO pins.
If unused, keep it
open.
SGMII_TX_M 123 AO
SGMII transmission
- minus
If unused, keep it
open.
SGMII_TX_P 124 AO SGMII transmission If unused, keep it
EC25_Hardware_DesignConfidential / Released 24 / 90
LTE Module Series
EC25Hardware Design
- plus open.
SGMII_RX_P 125 AI
SGMII_RX_M 126 AI
SGMII receiving
- plus
SGMII receiving
-minus
If unused, keep it
open.
If unused, keep it
open.
Wireless Connectivity Interfaces
Pin Name Pin No. I/O Description DC Characteristics Comment
V
max=0.45V
OL
V
min=1.35V
SDC1_
DATA3
SDC1_
DATA2
SDC1_
DATA1
SDC1_
DATA0
129 IO SDIO data bus D3
130 IO SDIO data bus D2
131 IO SDIO data bus D1
132 IO SDIO data bus D0
SDC1_CLK 133 DO SDIO clock
OH
V
min=-0.3V
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
V
max=0.45V
OL
V
min=1.35V
OH
V
min=-0.3V
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
V
max=0.45V
OL
V
min=1.35V
OH
V
min=-0.3V
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
V
max=0.45V
OL
V
min=1.35V
OH
V
min=-0.3V
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
V
max=0.45V
OL
V
min=1.35V
OH
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
V
max=0.45V
SDC1_CMD 134 DO SDIO command
PM_ENABLE 127 DO
WAKE_ON_
WIRELESS
135 DI
External power
control
Wake up the host
(EC25 module) by
OL
V
OH
V
max=0.45V
OL
V
OH
V
min=-0.3V
IL
V
max=0.6V
IL
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min=1.35V
min=1.35V
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
Active low.
LTE Module Series
EC25Hardware Design
FC20 module. VIHmin=1.2V
WLAN function
WLAN_EN 136 DO
control via FC20
module
COEX_UART
_RX
COEX_UART
_TX
WLAN_SLP_
CLK
137 DI
138 DO
118 DO WLAN sleep clock
BT_RTS* 37 DI
BT_TXD* 38 DO
LTE/WLAN&BT
coexistence signal
LTE/WLAN&BT
coexistence signal
BT UART request to
send
BT UART transmit
data
VIHmax=2.0V
V
max=0.45V
OL
V
min=1.35V
OH
V
min=-0.3V
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
V
max=0.45V
OL
V
min=1.35V
OH
V
min=-0.3V
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
V
max=0.45V
OL
V
min=1.35V
OH
If unused, keep it
open.
1.8V power domain.
Active high.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
V
min=-0.3V
BT_RXD* 39 DI
BT_CTS* 40 DO
BT_EN* 139 DO
BT UART receive
data
BT UART clear to
send
BT function control
via FC20 module
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
V
max=0.45V
OL
V
min=1.35V
OH
V
max=0.45V
OL
V
min=1.35V
OH
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
1.8V power domain.
If unused, keep it
open.
RF Interface
Pin Name Pin No. I/O Description DC Characteristics Comment
ANT_DIV 35 AI Diversity antenna 50ohm impedance
If unused, keep it
open.
ANT_MAIN 49 IO Main antenna 50ohm impedance
ANT_GNSS 47 AI GNSS antenna 50 ohm impedance
If unused, keep it
open.
GPIO Pins
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Pin Name Pin No. I/O Description DC Characteristics Comment
1.8V power domain.
Cannot be pulled up
before startup.
Low level wakes up
the module.
If unused, keep it
WAKEUP_IN 1 DI Sleep mode control
V
min=-0.3V
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
open.
1.8V power domain.
Pull-up by default.
In low voltage level,
module can enter into
airplane mode.
If unused, keep it
open.
W_DISABLE# 4 DI
Airplane mode
control
V
min=-0.3V
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
V
min=-0.3V
AP_READY 2 DI
Application
processor sleep
state detection
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
1.8V power domain.
If unused, keep it
open.
USB_BOOT Interface
Pin Name Pin No. I/O Description DC Characteristics Comment
V
min=-0.3V
USB_BOOT 115 DI
Force the module to
boot from USB port
IL
V
max=0.6V
IL
V
min=1.2V
IH
V
max=2.0V
IH
1.8V power domain.
If unused, keep it
open.
RESERVED Pins
Pin Name Pin No. I/O Description DC Characteristics Comment
3, 18, 23,
28~34, 43,
RESERVED
55, 73~84,
113, 114,
Reserved
Keep these pins
unconnected.
116, 117,
140~144
NOTES
1. “*” means under development.
2. Pads 24~27 are multiplexing pins used for audio design on EC25 module and BT function on FC20
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
Idle
Operation
Talk/Data
Minimum
Functionality
Mode
Airplane 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 USIM 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
Sleep Mode
level. During this mode, the module can still receive paging message, SMS, voice call
and TCP/UDP data from the network normally.
Power Down
Mode
In this mode, the power management unit shuts down the power supply. Software is
not active. The serial interface is not accessible. Operating voltage (connected to
VBAT_RF and VBAT_BB) remains applied.
3.5. Power Saving
Software is active. The module hasregistered onthe network, and it is
ready to send and receive data.
Network connection is ongoing. In this mode, the power consumption is
decided by network settingand data transfer rate.
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 procedure 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=1command 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 URC to report, RI signal will wake up the host. Refer to Chapter 3.16 for details
about RI behavior.
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
AT+QCFG=“apready”commandis 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 followingthreepreconditions
must be met tolet the module enter into the sleep mode.
Execute AT+QSCLK=1command to enable the sleep mode.
Ensure the DTR is held in 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 ModeApplication with USB Remote Wakeup
Sending data to EC25through USB will wake up the module.
When EC25has URC to report, the module will send remote wake-up signals viaUSB 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 threepreconditions to let the module enter into the sleep mode.
Execute AT+QSCLK=1command to enable the sleep mode.
Ensure the DTR is held in 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 EC25through USB will wake up the module.
When EC25has 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, you should disconnect USB_VBUS with additional
control circuit to let the module enter into sleep mode.
Execute AT+QSCLK=1commandto enable the sleep mode.
Ensure the DTR is held in high level or keep it open.
Disconnect USB_VBUS.
The following figure shows the connection between the module and the host.
ModuleHost
GPIO
USB_VBUS
USB_DP
USB_DM
RI
AP_READY
GND
Power
Switch
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.Refer to
document [1] for more details about EC25 power management application.
VDD
USB_DP
USB_DM
EINT
GPIO
GND
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+CFUNcommand provides the choice of the functionality level.
AT+CFUN=0: Minimum functionality mode; both USIM 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
byAT+QCFG=“airplanecontrol”command. This commandis 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 dedicated to connect with the external power supply. There are two
separate voltage domains for VBAT.
Two VBAT_RF pins for module RF part
Two VBAT_BB pins for module 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
VBAT_BB 59,60
8,9,19,22,
GND
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36,46,
48,50~54,56,
Power supply for module RF
part
Power supply for module
baseband part
Ground - 0 - V
3.3 3.8 4.3 V
3.3 3.8 4.3 V
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EC25Hardware Design
72, 85~112
3.6.2. Decrease Voltage Drop
The power supply range of the module is from 3.3Vto4.3V. 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.
Burst
Transmission
VBAT
Drop
Min.3.3V
Burst
Transmission
Ripple
Figure 7: Power Supply Limits during Burst Transmission
To decrease voltage drop, a bypass capacitor of about 100µF with low ESR should be used, and a
multi-layer ceramic chip (MLCC) capacitor array should also be used toprovide the low ESR. 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; andthe width of
VBAT_RF trace should be no less than 2mm.In principle, the longer the VBAT trace is, the wider it will be.
Three ceramic capacitors (100nF, 33pF, 10pF) are recommended to be applied to the VBAT pins. These
capacitors should be placed close to the VBAT pins. In addition, in order to get a stable power source, it is
suggested that you should use a zener diode of which reverse zener voltage is 5.1V and dissipation
power is more than 0.5W. 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, asthe performance of the module largely depends on the
power source. The power supply is capable of providing sufficient current up to 2A at least. If the voltage
drop between the input and output is not too high, it is suggested that you shoulduse an LDO 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 thepower 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, 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: PWRKEY Pin Description
Pin Name Pin No. Description DC CharacteristicsComment
max=2.1V
PWRKEY 21 Turn on/off the module
V
IH
V
min=1.3V
IH
V
max=0.5V
IL
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 100ms. 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.
Figure 10: Turn on the Module 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, aTVS component is indispensable to be placed nearby the
button for ESD protection. A reference circuit is shownin the following figure.
Figure 11: Turn on the Module Using Keystroke
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The turn on scenario is illustrated in the following figure.
LTE Module Series
Figure 12: Timing of Turning on Module
NOTE
Please make sure that VBAT is stable before pulling down PWRKEY pin. The time between them is 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+QPOWDcommand.
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 inthe 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+QPOWDcommand to turn off the module, which is similar to turning off the
module via PWRKEY pin.
Please refer todocument [2] for details about AT+QPOWD command.
NOTE
Inorder 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, the power supply can be
cut 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. Description DC Characteristics Comment
max=2.1V
V
IH
RESET_N 20 Reset the module
V
min=1.3V
IH
V
max=0.5V
IL
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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+QPOWDcommand and PWRKEY pin failed.
2. Ensure that there is no large capacitance on PWRKEY and RESET_N pins.
3.9. USIM Card Interface
The USIM card interface circuitrymeets ETSI and IMT-2000 SIM interface requirements. Both 1.8V and
3.0V USIM cards are supported.
Table 9: Pin Definition of the USIM Card Interface
Pin Name Pin No. I/O Description Comment
USIM_VDD 14 PO Power supply for USIM card
Either 1.8V or 3.0V is supported
by the module automatically.
USIM_DATA 15 IO Data signal of USIM card
USIM_CLK 16 DO Clock signal of USIM card
USIM_RST 17 DO Reset signal of USIM card
USIM_
PRESENCE
13 DI USIM card insertion detection
USIM_GND 10 Specified ground for USIM card
EC25 supports USIM card hot-plug via the USIM_PRESENCE pin. The function supports low level and
high level detections, and isdisabled by default. Please refer to document [2] about AT+QSIMDET
command for details.
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The following figure shows a reference design for USIM card interface with an 8-pin USIM card connector.
Figure 17: Reference Circuit of USIM Card Interface with an 8-Pin USIM Card Connector
If USIM card detection function is not needed, please keep USIM_PRESENCE unconnected. Areference
circuit for USIM card interface witha 6-pin USIM card connector is illustrated inthe following figure.
Figure 18: Reference Circuit of USIM Card Interface with a 6-Pin USIM Card Connector
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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 signals away from RF and VBAT traces.
Assure the ground between the module and the USIM card connector short and wide. Keep thetrace
width of ground and USIM_VDD no less than 0.5mm to maintain the same electric potential.
To avoid cross-talk between USIM_DATA and USIM_CLK, keep them away fromeach 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 50pF. The 22ohmresistors should be added in series between
the module and the USIM card so as to suppress EMI spurious transmission and enhance ESD
protection. The 33pFcapacitors are used for filtering interference of GSM900.Please note that the
USIM peripheral circuit should be close to the USIM card connector.
The pull-up resistor on USIM_DATA line can improve anti-jamming capability when long layout trace
and sensitive occasion areapplied, and should be placed close to the USIM card connector.
3.10. USB Interface
EC25 contains one integrated Universal Serial Bus (USB) transceiver 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 Signal Part
USB_DP 69 IO USB differential data bus (positive)
USB_DM 70 IO USB differential data bus (minus)
Require differential
impedance of 90Ω
Require differential
impedance of 90Ω
USB_VBUS 71 PI Used for detecting the USB connection Typical 5.0V
GND 72 Ground
For more details about the USB 2.0 specifications, please visithttp://www.usb.org/home
.
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The USB interface is recommended to be reserved for firmware upgrade in your design. The following
figure shows areference circuit of USB interface.
Figure 19: Reference Circuit of USB Application
In order to ensurethe integrity of USB data line signal, components R1, R2, R3 and R4 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.
In order to ensure the USB interface design corresponding with the USB 2.0 specification, please comply
with the following principles:
It is important to route the USB signal traces as differential pairs with total grounding. The impedance
of USB differential trace is 90ohm.
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 onnot 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 supports4800, 9600, 19200,38400,57600,115200,230400,460800,921600
and3000000bps 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 forLinux console and log output.
The following tables show the pin definition.
Table 11: Pin Definition of the Main UART Interface
Pin Name Pin No. I/O Description Comment
RI 62 DO Ring indicator 1.8V power domain
DCD 63 DO Data carrier detection 1.8V power domain
CTS 64 DO Clear to send 1.8V power domain
RTS 65 DI Request to send 1.8V power domain
DTR 66 DI Sleep mode control 1.8V power domain
TXD 67 DO Transmit data 1.8V power domain
RXD 68 DI Receive data 1.8V power domain
Table 12: Pin Definition of the 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 1.8V power domain
The logic levels are described in the following table.
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Table 13:Logic Levels of Digital I/O
Parameter Min. Max. Unit
VIL -0.3 0.6 V
VIH 1.2 2.0 V
VOL 0 0.45 V
VOH 1.35 1.8 V
The module provides 1.8V UART interface. A level translator should be used if your application is
equipped with a 3.3V UART interface. A level translator TXS0108EPWR provided by Texas Instrument is
recommended. The following figure shows a reference design.
Figure 20: Reference Circuit with Translator Chip
Please visit http://www.ti.com
for more information.
Another example with transistor translation circuit is shown as below. Thecircuit design of dotted line
section can refer to the design of solid line section, in terms of both module input and output circuit
designs, but please pay attention to the direction of connection.
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Figure 21: Reference Circuit with Transistor Circuit
NOTE
Transistor circuit solution is not suitable for applications with high baud rates exceeding 460Kbps.
3.12. PCM and I2C Interfaces
EC25 provides one Pulse Code Modulation (PCM) digital interface for audio design, which supports the
following modes:
Primary mode (short frame synchronization, works as both master and slave)
Auxiliary mode (long frame synchronization, works as master only)
In primary mode, the data is sampled on the falling edge of the PCM_CLK and transmitted on the rising
edge. The PCM_SYNC falling edge represents the MSB. In this mode, PCM_CLK supports
128,256,512,1024 and2048kHz for different speech codecs.
In auxiliary mode, the data is sampled on the falling edge of the PCM_CLK and transmitted on the rising
edge.The PCM_SYNC rising edge represents the MSB. In this mode, PCM interface operates with a
128kHz PCM_CLK and an 8kHz, 50% duty cycle PCM_SYNC only.
EC25 supports 8-bit A-law* andμ-law*, and also 16-bit linear data formats. The following figures show
theprimary mode’s timing relationship with 8kHz PCM_SYNC and 2048kHz PCM_CLK, as well asthe
auxiliary mode’s timing relationship with 8kHz PCM_SYNC and 128kHz PCM_CLK.
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Figure 22: Primary Mode Timing
Figure 23: Auxiliary Mode Timing
The following table shows the pin definition of PCM and I2C interfaces which can be applied on audio
codec design.
Table 14: Pin Definition of PCM and I2C Interfaces
Pin Name Pin No. I/O Description Comment
PCM_IN 24 DI PCM data input 1.8V power domain
PCM_OUT 25 DO PCM data output 1.8V power domain
PCM_SYNC 26 IO PCM data frame sync signal 1.8V power domain
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PCM_CLK 27 IO PCM data bit clock 1.8V power domain
I2C_SCL 41 OD I2C serial clock Require external pull-up to 1.8V
I2C_SDA 42 OD I2C serial data Require external pull-up to 1.8V
Clock and mode can be configured by AT command, and the default configuration is master mode using
short frame synchronization format with 2048kHzPCM_CLK and 8kHz PCM_SYNC.Please refer to
document [2] about AT+QDAIcommand for details.
The following figure shows areference design of PCM interface with external codec IC.
Figure 24: Reference Circuit of PCM Application with Audio Codec
NOTES
1. “*” means under development.
2. It is recommended to reserve RC (R=22ohm, C=22pF) circuit on the PCM lines, especially for
PCM_CLK.
3. EC25 works as a master device pertaining to I2C interface.
3.13. ADC Function
The module provides two analog-to-digital converters (ADC).AT+QADC=0command can be used toread
the voltage value on ADC0 pin. AT+QADC=1command can be used to read the voltage value on ADC1
pin. For more details about these AT commands, please refer todocument [2].
In order to improve the accuracy of ADC, the trace of ADC should be surrounded by ground.
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Table 15: Pin Definition of the ADC
Pin Name Pin No. Description
ADC0 45 General purpose analog to digital converter
ADC1 44 General purpose analog to digital converter
The following table describes the characteristic of the ADC function.
Table 16: Characteristic of the ADC
Parameter Min. Typ. Max. Unit
ADC0 Voltage Range 0.3 VBAT_BB V
ADC1 Voltage Range 0.3 VBAT_BB V
ADC Resolution 15 bits
NOTES
1. ADC input voltage must not exceed VBAT_BB.
2. It is prohibited to supply any voltage to ADC pinswhen VBAT is removed.
3. It is recommended to use resistor divider circuit for ADC application.
3.14. Network Status Indication
The network indication pins can be used to drive network status indication LEDs. The module provides
two pins which are NET_MODE and NET_STATUS. The following tables describe pin definition and logic
level changes in different network status.
Table 17: Pin Definition of Network Connection Status/Activity Indicator
Pin Name Pin No. I/O Description Comment
NET_MODE1) 5 DO
NET_STATUS 6 DO
Indicate the module network
registration mode.
Indicate the module network activity
status.
1.8V power domain
1.8V power domain
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1)
meansthat this pin cannot be pulled up before startup.
Table 18: Working State of the Network Connection Status/Activity Indicator