Neoway N720 Installation manual

N720 Hardware User Guide ()
N720 Hardware User Guide
Version 1.6

N720 Hardware User Guide
Copyright © Neoway Technology Co., Ltd i
Copyright
Copyright © 2018 Neoway Technology Co., Ltd. All rights reserved.
No part of this document may be reproduced or transmitted in any form or by any means without
prior written consent of Shenzhen Neoway Technology Co., Ltd.
is the trademark of Shenzhen Neoway Technology Co., Ltd.
All other trademarks and trade names mentioned in this document are the property of their respective
holders.
Notice
This document provides guide for users to use the N720.
This document is intended for system engineers (SEs), development engineers, and test engineers.
The information in this document is subject to change without notice due to product version update
or other reasons.
Every effort has been made in preparation of this document to ensure accuracy of the contents, but all
statements, information, and recommendations in this document do not constitute a warranty of any
kind, express or implied.
Shenzhen Neoway provides customers complete technical support. If you have any question, please
contact your account manager or email to the following email addresses:
[email protected]
[email protected]
Website: http://www.neoway.com

N720 Hardware User Guide
Copyright © Neoway Technology Co., Ltd ii
Revision Record
Version
Changes
Revised By
Date
V1.0
Initial draft
Li Qiusheng
2016-04
V1.1
Added bands information of different areas
Dong Liuting
2016-09
V1.2
Modified pin the description
Dong Liuting
2016-10
V1.3
Deleted UIM2
Added band information of different areas
Modified some pin definition: RING is changed to
the 13th pin, LIGHT is changed to the 83rd pin
Dong Liuting
2016-12
V1.4
Modified recommended circuit 1 for UART.
Added recommend circuit 2 for UART
Wang Qiang
2017-02
V1.5
Added LTE B12 to the US version
Added memory and dimensions tolerance
Modified the description of the PWRKEY and
RESET pins
Dong Liuting
2017-07
V1.6
Updated variants and bands
Added SDIO, PCM, and I2C
Added GNSS parameters
Modified some description
Dong Liuting
2018-01

N720 Hardware User Guide
Copyright © Neoway Technology Co., Ltd iii
Contents
1 Introduction to N720......................................................................................................... 1
1.1 Overview ............................................................................................................................................ 1
1.2 Block Diagram ................................................................................................................................... 2
1.3 Features .............................................................................................................................................. 3
2 Application Interfaces ...................................................................................................... 5
2.1 Specifications and Pin Definition ....................................................................................................... 5
2.2 Pin Description ................................................................................................................................... 6
2.3 Power Control Interfaces.................................................................................................................. 14
2.3.1 VBAT ...................................................................................................................................... 14
2.3.2 VDDIO_1P8............................................................................................................................ 18
2.3.3 ON/OFF .................................................................................................................................. 18
2.3.4 RESET .................................................................................................................................... 20
2.4 USB Interface ................................................................................................................................... 21
2.5 UIM Card Interface .......................................................................................................................... 22
2.6 GPIO Interfaces................................................................................................................................ 23
2.6.1 UART ...................................................................................................................................... 24
2.6.2 ADC ........................................................................................................................................ 26
2.6.3 NET_LIGHT........................................................................................................................... 27
2.6.4 DTR......................................................................................................................................... 27
2.6.5 RING Signal Indicator ............................................................................................................ 28
2.7 AUDIO Interfaces............................................................................................................................. 29
2.7.1 PCM ........................................................................................................................................ 29
2.7.2 I2C........................................................................................................................................... 31
2.8 WLAN Interfaces ............................................................................................................................. 31
2.8.1 SDIO ....................................................................................................................................... 31
2.8.2 WLAN Control........................................................................................................................ 33
2.9 Commissioning Interfaces ................................................................................................................ 35

N720 Hardware User Guide
Copyright © Neoway Technology Co., Ltd iv
2.9.1 FORCE_USB_BOOT ............................................................................................................. 35
3 RF Interface....................................................................................................................... 36
3.1 2G/3G/4G RF Design and PCB Layout............................................................................................ 36
3.2 GNSS RF Design and PCB Layout .................................................................................................. 38
3.2.1 GNSS Impedance .................................................................................................................... 38
3.2.2 Active GNSS Antenna Design................................................................................................. 38
4 Electrical Features and Reliability ............................................................................... 40
4.1 Electrical Features ............................................................................................................................ 40
4.2 Temperature Features ....................................................................................................................... 40
4.3 ESD Features.................................................................................................................................... 41
5 RF Feature ......................................................................................................................... 42
5.1 Operating Band................................................................................................................................. 42
5.2 TX Power and RX Sensitivity .......................................................................................................... 43
5.3 GNSS Features ................................................................................................................................. 44
6 Mechanical Feature ......................................................................................................... 45
6.1 Dimensions....................................................................................................................................... 45
6.2 PCB Foot Print ................................................................................................................................. 46
7 Mounting and Packaging............................................................................................... 47
7.1 Mounting the Module onto the Application Board ........................................................................... 47
7.2 Packaging ......................................................................................................................................... 47
8 SMT Temperature Curve ............................................................................................... 48
9 Abbreviations................................................................................................................... 49

N720 Hardware User Guide
Copyright © Neoway Technology Co., Ltd v
Table of Figures
Figure 1-1 N720 block diagram............................................................................................................... 3
Figure 2-1 N720 module pin definition (Top View) ................................................................................ 5
Figure 2-2 Current peaks and voltage drops .......................................................................................... 14
Figure 2-3 Capacitors used for the power supply .................................................................................. 15
Figure 2-4 Reference design of power supply control........................................................................... 15
Figure 2-5 Reference design of power supply controlled by p-MOSFET ............................................. 16
Figure 2-6 Reference designs of separated power supply...................................................................... 17
Figure 2-7 Push switch control .............................................................................................................. 18
Figure 2-8 MCU control ........................................................................................................................ 18
Figure 2-9 N720 power-on/off sequence ............................................................................................... 19
Figure 2-10 N720 power-off sequence .................................................................................................. 19
Figure 2-11 Reset controlled by button ................................................................................................. 20
Figure 2-12 Reset circuit with triode separating.................................................................................... 20
Figure 2-13 N720 reset sequence........................................................................................................... 20
Figure 2-14 USB circuit......................................................................................................................... 21
Figure 2-15 Reference design of SIM card interface............................................................................. 22
Figure 2-16 UIM connector encapsulation ............................................................................................ 23
Figure 2-17 Reference design of the UART interface ........................................................................... 24
Figure 2-18 Recommended level shifting circuit 1................................................................................ 25
Figure 2-19 Recommended level shifting circuit 2................................................................................ 26
Figure 2-20 LED indicator driven by transistor..................................................................................... 27
Figure 2-21 RING indicator for incoming call ...................................................................................... 28
Figure 2-22 RING indicator for SMS .................................................................................................... 28
Figure 2-23 PCM connection................................................................................................................. 29
Figure 2-24 PCM synchronization timing ............................................................................................. 29
Figure 2-25 PCM data input timing....................................................................................................... 30
Figure 2-26 PCM data output timing..................................................................................................... 30
Figure 2-27 SDIO connection................................................................................................................ 32
Figure 2-28 SDIO SDR timing .............................................................................................................. 32
Figure 2-29 SDIO DDR timing ............................................................................................................. 33
Figure 2-30 32KHz clock signal timing ................................................................................................ 34
Figure 2-31 Reference design of the fast boot interface ........................................................................ 35

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Copyright © Neoway Technology Co., Ltd vi
Figure 3-1 Reference of antenna matching design................................................................................. 36
Figure 3-2 Recommended RF PCB design............................................................................................ 37
Figure 3-3 Encapsulation specifications of Murata RF connector......................................................... 37
Figure 3-4 RF connections..................................................................................................................... 37
Figure 3-5 GNSS RF structure .............................................................................................................. 38
Figure 3-6 Power supply reference for active antenna .......................................................................... 39
Figure 6-1 Dimensions of N720 ............................................................................................................ 45
Figure 6-2 N720 PCB foot print (Top View) ......................................................................................... 46
Figure 8-1 Temperature curve................................................................................................................ 48

N720 Hardware User Guide
Copyright © Neoway Technology Co., Ltd vii
Table of Tables
Table 1-1 N720 baseband and wireless features...................................................................................... 3
Table 2-1 N720 dimensions..................................................................................................................... 5
Table 2-2 N720 pin description ............................................................................................................... 6
Table 2-3 GPIO...................................................................................................................................... 23
Table 2-4 Timing parameters of PCM interface .................................................................................... 30
Table 2-5 Timing parameters of SDIO interface ................................................................................... 33
Table 2-6 Timing parameters of 32KHz clock signal ............................................................................ 34
Table 4-1 N720 electric features............................................................................................................ 40
Table 4-2 Temperature feature............................................................................................................... 40
Table 4-3 N720 ESD features................................................................................................................ 41
Table 5-1 N720 operating band ............................................................................................................. 42
Table 5-2 N720 RF power and RX sensitivity....................................................................................... 43
Table 5-3 GNSS parameters .................................................................................................................. 44

N720 Hardware User Guide
Copyright © Neoway Technology Co., Ltd 1
1 Introduction to N720
1.1 Overview
N720 is an industrial-grade 4G module developed on Qualcomm platform. Its dimensions are 30 mm x 28
mm x 2.8 mm. This module has an ultra-wide operating temperature range of -40 °C to +85 °C and
electrostatic capacity of 8 kV. N720 is well applicable to develop wireless meter reading terminal,
in-vehicle computers, POS, industrial routers, and other IoT terminals with the following features:
ARM Cortex-A7 processors, 1.3 GHz main frequency, 256 KB L2 cache, 28 nm process technology
GSM/GPRS/EDGE &CDMA2000 1x/1xAdvanced/1xEV-DOrA &&WCDMA R99 to
DC-HSPA+&&TD-SCDMA&LTE Cat4
USB2.0/ UIM/ADC/UART/GNSS (optional) /SDIO/PCM/I2C
N720 series include the following versions to meet the band requirements in different areas:
Module
Version
Area
Category
Band
N720
CA
China
Cat4
FDD-LTE: B1, B3, B5, B8
TDD-LTE: B38, B39, B40, B41
TD-SCDMA: B34, B39
UMTS: B1, B8
EV-DO: BC0
CDMA 1x: BC0
GSM/GPRS/EDGE: 900/1800 MHz
CB
China/India
Cat4
FDD-LTE: B1, B3, B5, B8
TDD-LTE: B38, B39, B40, B41
TD-SCDMA: B34, B39
UMTS: B1, B8
GSM/GPRS/EDGE: 900/1800 MHz
CC
China
Cat4
FDD-LTE: B1, B3, B8, B28
TDD-LTE: B38, B39, B40, B41
TD-SCDMA: B34, B39
UMTS: B1, B8
GSM/GPRS/EDGE: 900/1800 MHz
EA
Europe
Cat4
FDD-LTE: B1, B3, B5, B7, B8, B20
TDD-LTE: B40
UMTS: B1, B8
GSM/GPRS/EDGE: 850/900/1800/1900 MHz
EB
Europe
Cat4
FDD-LTE: B1, B3, B5, B7, B8, B20

N720 Hardware User Guide
Copyright © Neoway Technology Co., Ltd 2
TDD-LTE: B38
UMTS: B1, B8
GSM/GPRS/EDGE: 900/1800 MHz
NA
North America
Cat4
FDD-LTE: B2, B4, B5, B7, B12, B17
UMTS: B2, B4, B5
GSM/GPRS/EDGE: 850/900/1800/1900 MHz
A
US ATT
Cat4
FDD-LTE: B2, B4, B12, B17
UMTS: B2, B4, B5
V
US Verizon
Cat4
FDD-LTE: B4, B13
AU
Australia/New
Zealand/the
Philippines
Cat4
FDD-LTE: B1, B3, B5, B7, B28
TDD-LTE: B40
UMTS: B1, B5
TWN
Taiwan
Cat4
FDD-LTE: B1, B3, B7, B8, B28
UMTS: B1, B8
GSM/GPRS/EDGE: 900/1800 MHz
IN
India
Cat4
FDD-LTE: B3, B5
TDD-LTE: B40
1.2 Block Diagram
Figure 1-1 shows the block diagram of N720.

N720 Hardware User Guide
Copyright © Neoway Technology Co., Ltd 3
Figure 1-1 N720 block diagram
VBAT
Power
Manager RF transceiver
MCP
19.2 M
crystal
RF Section
Base Band
I2C
Digital Interface
USBUART
SIM
PC
ANT_MAIN ANT_AUX ANT_GNSS
PWRKEY
RESET
ADC
UIM PCM SDIO
1.3 Features
Table 1-1 N720 baseband and wireless features
Specifications
Description
Power supply
VBAT: 3.3V to 4.3V; Typical value: 3.8 V
Current in sleep mode
< 4 mA
Standby current
< 20 mA
Operating temperature
-40 °C to +85 °C
Processor
ARM Cortex-A7 processor
Main frequency: 1.3 GHz
256 kB L2 cache

N720 Hardware User Guide
Copyright © Neoway Technology Co., Ltd 4
Memory
RAM: 128 MB or 256 MB
ROM: 256 MB
Band
See Table 1-1.
Rate
GPRS: Max 85.6 Kbps(DL) / Max 85.6 Kbps(U)
CDMA: Max 3.1 Mbps (DL) / Max 1.8 Mbps (UL)
WCDMA: DC-HSPA+, Max 42 Mbps(DL)/Max 5.76 Mbps(UL)
TD-SCDMA: Max 4.2 Mbps(DL)/Max 2.2 Mbps(UL)
FDD-LTE: non-CA cat4, Max 150 Mbps(DL)/Max 50 Mbps(UL)
TDD-LTE: non-CA cat4, Max 130 Mbps(DL)/Max 35 Mbps(UL)
Transmit power
GSM850: +33 dBm (Power Class 4)
EGSM900: +33 dBm (Power Class 4)
DCS1800: +30 dBm (Power Class 1)
PCS1900: +30 dBm (Power Class 1)
EDGE 850 MHz: +27 dBm (Power Class E2)
EDGE 900 MHz: +27 dBm (Power Class E2)
EDGE 1800 MHz: +26 dBm (Power Class E2)
EDGE 1900 MHz: +26 dBm (Power Class E2)
TD-SCDMA:+23 dBm (Power Class 3)
CDMA 1X/EVDO:+23 dBm(Power Class 3)
UMTS: 23 dBm (Power Class 3)
LTE: +23 dBm (Power Class 3)
Antenna feature
2G/3G/4G antenna, 4G diversity antenna, GNSS antenna, 50 Ω impedance
UART
At most 4 Mbps, 1 UART interface
UIM
1 UIM interface, 1.8V/3V dual-voltage adaptive
USB
1 USB2.0 high-speed interface
ADC
2 15-bit ADC interfaces, detectable voltage ranging from 0.1 V to 1.7 V
SDIO
1 SDIO interface, used for WLAN
PCM
1 PCM interface
I2C
1 I2C interface, supports host mode only

N720 Hardware User Guide
Copyright © Neoway Technology Co., Ltd 5
2 Application Interfaces
N720 adopts 100-pin LGA encapsulation package.
2.1 Specifications and Pin Definition
Table 2-1 N720 dimensions
Specifications
N720
Dimensions (H x W x D)
28±0.1 mm x 30±0.1 mm x 2.8±0.1 mm
Weight
5.1 g
Package
100-pin LGA
Figure 2-1 N720 module pin definition (Top View)

N720 Hardware User Guide
Copyright © Neoway Technology Co., Ltd 6
2.2 Pin Description
IO: input/output
DI: Digital input
DO: Digital output
PI: Power input
PO: Power output
AI: Analog input
AO: Analog output
Table 2-2 N720 pin description
Name
Pin
I/O
Function
Level Feature (V)
Power
Domain
Remarks
Power Supply
VBAT
27, 28, 29
PI
Main power supply
Vmax=4.3 V
Maximum supply current of 2A peak.
VDDIO _1P8
45
PO
1.8 V power supply
Vnorm=1.8 V;
Imax=50 mA;
1.8 V
Supply power for IO level shifting circuit.
Leave this pin unconnected if it is not used.
GND
1, 14, 17, 20,
26, 30, 31,
44, 49, 74,
75, 77, 91,
93, 95, 97,
98, 99, 100
GND
Power on/off and reset
RESET
32
DI
Reset input
VIL min=-0.3 V;
VIL max=0.5 V;
VIH min=1.2 V;
1.8 V
Low level triggers the reset.

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VIH max=2.1 V
PWRKEY
33
DI
Power ON/OFF
VIL min=-0.3 V;
VIL max=0.5 V;
VIH min=1.2 V;
VIH max=2.1 V
Low level triggers the ON/OFF state.
There is switch diode inside the module.
It is internally pulled up by a 200 kΩresistor.
The level at the pin is 0.8 when it is left
unconnected.
200KΩ
1.8V
PM
PWRKEY
PON_TRIG
34
DI
PON_TRIG
VIL min=-0.3 V;
VIL max=0.5 V;
VIH min=1.2 V;
VIH max=2.1 V
1.8 V
High level triggers the ON status.
It is connected to ground through an internally
200 kΩpull-down resistor.
Ground it if it is not used.
UART
UART2_TXD
46
DO
UART data transmit
VOL max=0.45 V;
VOH min=1.35 V;
1.8 V
Data transmission
Leave these pins unconnected if they are not
used.
UART2_RXD
47
DI
UART data receive
VIL min=-0.3 V;
VIL max=0.45 V;
VIH min=1.35 V;
VIH max=2.1 V
1.8 V
UART2_CTS
51
DI
Clear to send
VIL min=-0.3 V;
VIL max=0.45 V;
VIH min=1.35 V;
VIH max=2.1 V
1.8 V
Leave these pins unconnected if they are not
used.

N720 Hardware User Guide
Copyright © Neoway Technology Co., Ltd 8
UART2_RTS
52
DO
Request to send
VOL max=0.45 V;
VOH min=1.35 V
1.8 V
UIM
VUIM
35
PO
UIM power supply
output
1.8V USIM:
Vmax = 1.9 V ;
Vmin = 1.7 V
3V USIM:
Vmax = 3.05 V;
Vmin = 2.7 V;
IO max =50 mA
1.8 V/3 V
Compatible with 1.8/3V UIM card
UIM_RESET
38
DO
UIM reset
1.8 V USIM:
VOL max = 0.45 V;
VOH min = 1.35 V
3 V USIM:
VOL max = 0.4 V;
VOH min = 2.6V
1.8 V/3 V
UIM_DATA
36
IO
UIM data
1.8V USIM:
VIL max = 0.6 V;
VIH min = 1.2 V;
VOL max = 0.45 V;
VOH min = 1.35 V
3V USIM:
VIL max = 0.8 V
VIH min = 1.95 V
VOL max = 0.45 V
VOH min = 2.6 V
1.8 V/3 V

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UIM_CLK
37
DO
UIM clock
1.8 V USIM:
VOL max = 0.45 V;
VOH min = 1.35 V
3V USIM:
VOL max = 0.4 V
VOH min = 2.6 V
1.8 V/3 V
UIM_DETECT
39
DI
UIM detect
VIL min = -0.3 V;
VIL max = 0.63 V
1.8 V
USB
VBUS
40
PI
USB voltage test
3.3 V~5.2 V,
typically 5 V
Used for firmware download and data
transmission
Differential trace for DM and DP with 90 Ω
impedance
USB_DM
41
IO
USB data negative
signal
USB2.0
USB_DP
42
IO
USB data positive
signal
USB2.0
USB _ID
43
AI
Identify host and
device
1.8 V
Leave this pin unconnected if it is not used.
Audio (Optional)
PCM_CLK
9
IO
PCM clock signal
VOL max=0.45V;
VOH min=1.35V
1.8V
The audio function is optional. It requires
PCM, I2C, and I2S_MCLK signals. Leave
these pins unconnected if they are not used.
PCM_DOUT
10
DO
PCM data output
VOL max=0.45V;
VOH min=1.35V
1.8V
PCM_DIN
11
DI
PCM data input
VIL min=-0.3V;
VIL max=0.45V;
VIH min=1.6V;
1.8V

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Copyright © Neoway Technology Co., Ltd 10
VIH max=2.1V
PCM_SYNC
12
IO
PCM sync signal
VOL max=0.45V;
VOH min=1.35V;
VIL min=-0.3V;
VIL max=0.45V;
VIH min=1.6V;
VIH max=2.1V
1.8V
I2S_MCLK
64
DO
I2S main clock output
signal
1.8V
Leave this pin unconnected if it is not used.
I2C_SDA
81
IO
I2C data
VOL max=0.45V;
VOH min=1.35V;
VIL min=-0.3V;
VIL max=0.45V;
VIH min=1.6V;
VIH max=2.1V
1.8V
Connected to a 2.2K pull-up resistor internally.
Leave them pin unconnected if they are not
used.
I2C_SCL
82
DO
I2C clock
VOL max=0.45V;
VOH min=1.35V
1.8V
WLAN (Optional)
LTE_COEX_RX_UART
48
DI
WLAN/LTE co-exist
control receive
VIL min=-0.3V
VIL max=0.45V
VIH min=1.35V
VIH max=2.1V
1.8V
Multiplexing function of
FORCE_USB_BOOT
Leave this pin unconnected if it is not used.
LTE_COEX_TX_UART
50
DO
WLAN/LTE co-exist
control transmit
VOL max=0.45V;
VOH min=1.35V
1.8V
Leave this pin unconnected if it is not used.
VDDXO_1P8
53
PO
1.8V power supply
output
Vnorm=1.8V
1.8V
Used to connect to the crystalloid of the
external WLAN chipset via a pull-up resistor.

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Imax=20mA
Leave this pin unconnected if it is not used.
SDIO_CMD
54
IO
SDIO IO control
signal
VIL max = 0.6V
VIH min = 1.3V
VOL max = 0.45V
VOH min = 1.4V
1.8V
Leave this pin unconnected if it is not used.
SDIO_CLK
55
DO
SDIO clock signal
1.8V
Leave this pin unconnected if it is not used.
SDIO_DATA_0
56
IO
SDIO data
output/input
VIL max = 0.6V
VIH min = 1.3V
VOL max = 0.45V
VOH min = 1.4V
1.8V
Leave this pin unconnected if it is not used.
SDIO_DATA_1
57
IO
SDIO data IO
VIL max = 0.6V
VIH min = 1.3V
VOL max = 0.45V
VOH min = 1.4V
1.8V
Leave this pin unconnected if it is not used.
SDIO_DATA_2
58
IO
SDIO data IO
VIL max = 0.6V
VIH min = 1.3V
VOL max = 0.45V
VOH min = 1.4V
1.8V
Leave this pin unconnected if it is not used.
SDIO_DATA_3
59
IO
SDIO data IO
VIL max = 0.6V
VIH min = 1.3V
VOL max = 0.45V
VOH min = 1.4V
1.8V
Leave this pin unconnected if it is not used.
WAKE_ON_WIRELESS
60
DO
WLAN mode control
signal
VOL max=0.45V
VOH min=1.35V
1.8V
Leave this pin unconnected if it is not used.
WLAN_SLEEP_CLK
61
DO
WIFI sleep clock
1.8V
Leave this pin unconnected if it is not used.

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signal
WLAN_EN
62
DO
WLAN enable control
VOL max=0.45V
VOH min=1.35V
1.8V
Leave this pin unconnected if it is not used.
WLAN_3V_EN
63
DO
WLAN external LDO
enable control
VOL max=0.45V
VOH min=1.35V
1.8V
Leave this pin unconnected if it is not used.
ADC
ADC2
88
AI
Analog-to-digital
signal conversion
Vmax=1.7 V;
Vmin=0.1 V
1.8 V
15-bit, detectable voltage range: 0.1 V to 1.7 V
ADC1
89
AI
Analog-to-digital
signal conversion
Vmax=1.7 V;
Vmin=0.1 V
1.8 V
RING
RING
13
DO
Incoming call ring
VOL max=0.45 V;
VOH min=1.35 V;
1.8 V
Leave this pin unconnected if it is not used.
Sleep mode control
DTR
79
DI
Sleep mode control
VIL min=-0.3V;
VIL max=0.45V;
VIH min=1.35V;
VIH max=2.1V
1.8V
Leave this pin unconnected if it is not used.
Network indicator
NET_LIGHT
83
DO
Network status
indicator control
VOL max=0.45 V;
VOH min=1.35 V;
1.8 V
Leave this pin unconnected if it is not used.
Other Pins
FORCE_USB_BOOT
48
DI
External GNSS LNA
VIL min=-0.3V;
1.8 V
Leave this pin unconnected if it is not used.