Lierda L-LRNTB25-97UN4 LoRa Standard Module User Manual
- July 13, 2024
- lierda
Table of Contents
Lierda L-LRNTB25-97UN4 LoRa Standard Module
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this manual at any time.
Introduction
This document defines the standard application development specifications for the L-LRNTB25-97UN4 module (hereinafter referred to as the module), and describes its hardware interfaces, electrical characteristics, application methods, and mechanical specifications.
This document can help users quickly understand the hardware interface specifications, electrical, mechanical characteristics and other related information of the module, combined with other relevant documents, you can quickly master the application development method of the module.
Product Overview
The L-LRNTB25-97UN4 is a LoRaWAN End Node module developed by Lierda Internet of Things Technology Co., LTD. The module uses serial interface to exchange data and instructions with user equipment, which can easily provide users with fast LoRaWAN network access and wireless data transmission functions. The module supports three working modes: sleep, receive and transmit. Users can choose the appropriate working mode according to their own application scenarios. The module has many characteristics, such as wide transmitting power range, low receiving sensitivity and strong anti-interference ability.
Product Features
| Main Parameters | Instructions |
|---|---|
| Operating frequency | 860~930MHz |
| Modulation mode | LoRa |
| Receiving sensitivity | -124dBm@PER=5%_SF7_BW125 |
| Maximum transmitting power | 22dBm@25℃ |
| Communication interface | UART |
| Supply voltage | DC 3.3V |
| Transmit current | Avg.120mA@TX power_22dBm |
Avg.8.5mA@RX
Dimension| 17.7×15.8×2.4mm
Operating temperature| -40~+85℃
Hardware block diagram
Pin definition
Module pin description
UART
Table 1-1 Serial port pin description
Pin Name| Pin No.| Instructions| Pin Type| Dc
characteristic| Remarks
---|---|---|---|---|---
UART_TXD| 17| UART| O| –|
UART_RXD| 18| UART| I| –
DEBUG_RXD| 38| UART| I| –|
DEBUG_TXD| 39| UART| O| –|
Power
Table 1-2 Power supply pin description
Pin Name| Pin No.| Instructions| Pin Type| Dc
characteristic| Remarks
---|---|---|---|---|---
VDD| 42、43| Power| PI| Vmin= 2V Vtype= 3.3V Vmax= 3.7V|
VDD_EXT| 24| Power| PO| |
GND| 1、10、27、
34、36、
37、40、
41、56、
57、58
| GND| G| –|
SWD
Table 1-3 SWD pin description
Pin Name
|
Pin No.
|
Instructions
|
Pin Type
|
Dc characteristic
|
Remarks
---|---|---|---|---|---
SWDIO| 2| SWD| I/O| –|
SWCLK| 3| SWD| I| –|
---|---|---|---|---|---
Functional Pin Interfaces
Table 1-4 Module function pin description
Pin Name| Pin No.| Instructions| Pin Type| Dc
characteristic| Remarks
---|---|---|---|---|---
P0| 4| Reserve| I/O| –|
Default high resistance state
P1| 5| Reserve| I/O| –
P2| 6| Reserve| I/O| –
BOOT| 7| –| I| –| Default low
P3| 8| Reserve| I/O| –| Default high
resistance state
RESET_N| 15| Reset| I| –| Active low
WAKE| 19| –| I| –|
MODE| 20| –| I| –|
STAT| 21| –| O| –|
BUSY| 22| –| O| –| Default high
NC
| 9、11、
12、13、
14、16、
23、25、
26、28、
29、30、
31、32、
33、44、
45、46、
47、48、
49、50、
51、52、
53、54、
55
|
–
|
–
|
–
|
NC
ANT
Table 1-5 ANT function pin description
Pin Name| Pin No.| Instructions| Pin Type| Dc
characteristic| Remarks
---|---|---|---|---|---
ANT_RF| 35| ANT| I/O| –|
Remarks
Pin type: “O”=Output, “I”= Input, “P”=Power, “G”=Ground
Operating characteristics
Working mode
Table 3-1 working mode
| Working mode | Module state |
|---|---|
| Normal working mode | Networking status Users can initiate communication |
through serial port commands
Sleep mode| In low-power state, the user needs to wake up the module and then
initiate communication through the serial port command
Power supply circuit
VDD is the input end of the whole module power supply, and the power supply
directly affects the performance of the module. During the design, a power
supply capable of providing at least 0.3A current must be selected to ensure
that the input voltage to the VDD is not lower than the minimum operating
voltage to prevent abnormal operation of the module due to voltage drop.
If the pressure difference between the input voltage and the power supply voltage of the module is not very large, it is recommended to choose LDO as the power supply. If there is a relatively large pressure difference between the input and output, DC-DC is used for power conversion, and EMI problems caused by DC/DC should be paid attention to.
The power wiring is as short as possible and the GND plane of the power supply part should be as complete as possible and have more ground holes, and the capacitor should be as close as possible to the VDD pin of the module.
RESET
The reset pin of the module remains at a low level of 100 subtle or above, and
the module is reset
Typical reference design circuit
The following is the typical design circuit of the module, and the use of
other pins should be adjusted according to the actual application
requirements.
When the VDD of the module is 3.3V, if the terminal serial port is not 3.3V
level, the serial port level conversion circuit needs to be added.
Specification parameter
Absolute maximum ratings
Only the maximum load that can be borne is given here, and it does not mean
that the functional operation of the device under these conditions is correct.
The reliability of the device may be affected if the device works at the
maximum value for a long time.
Table 5-1 Absolute maximum ratings
| Main Parameters | Minimum | Maximum | Uints | Remarks |
|---|---|---|---|---|
| Supply voltage | -0.3 | +3.9 | V | |
| Max RF input power | – | +10 | dBm | ANT port |
Operating Range
Main Parameters| Minimum| Typical| Maximum| Uints|
Remarks
---|---|---|---|---|---
Supply voltage| +2| +3.3| +3.7| V|
Operating temperature| -40| –| +85| ℃|
Storage temperature| -40| –| +85| ℃|
Table 5-3 Digital logic level characteristics
| Main Parameters | Minimum | Typical | Maximum | Remarks |
|---|---|---|---|---|
| VIH(V) | 0.7*VDD | – | – | |
| VIL(V) | – | – | 0.3*VDD | |
| VOH(V) | VDD-0.45 | – | – |
2V≤VDD≤3.7V
VOL(V)| –| –| 0.4
Table 5-4 Radio-frequency parameter
Main
Parameters
| Minimum| Typical| Maximum| Uints| Remarks
---|---|---|---|---|---
Operating frequency
|
860
|
–
|
930
|
MHz
| The module hardware supports the 860-930MHz band. The specific operating band is selected according to the user’s
software configuration.
TX power
|
20.5
|
21
|
22
|
dBm
| VDD=+3.3V@25 ℃ ; At 25 ℃ ,
the operating voltage VDD ≥ 3.2V, the maximum transmitting power ≥20.5dBm; When 2.7V
≤ VDD < 3.2V, the maximum
transmit power ≥ 17.5dBm; When 2V ≤ VDD < 2.7V, the maximum transmitting power is
≥14.5dBm;
Transmit current| –| 120| 135| mA| TX power@22dBm
–| 8.5| 10.5| mA| RX
Sleep current| –| 2| 3| uA|
Receiving
sensitivity
| -125| -124| -123| dBm| SF7_BW125
Note
- The test conditions are: temperature: 25℃, center frequency: 863.1MHz/902.1MHz, working voltage: 3.3V; Unless otherwise specified, all test temperatures are 25℃, the same below.
- The user can configure the working frequency band according to the local regulations of the terminal market, and must comply with the local regulations. If the frequency band is not allowed by the regulations, our company does not assume any responsibility. For domestic terminal market applications, please refer to the Catalogue and Technical Requirements of Micro-power Short-range Radio Transmission Equipment.
Mechanical dimension
Dimension drawing
Operation Instruction
Steel mesh opening design
In principle, the thickness selection of the steel network on the bottom plate
is selected according to the comprehensive consideration of the packaging type
of the devices in the plate, and the following requirements should be focused
on:
The module pad position can be locally thickened to 0.15~0.20mm to avoid air
welding.
Reflux welding operation instruction
Note : This operation instruction is only suitable for lead-free
operations and is for reference only.
Federal Communication Commission (FCC) Radiation Exposure Statement
When using the product, maintain a distance of 20cm from the body to ensure
compliance with RF exposure requirements.
This device complies with part 15 of the FCC rules. Operation is subject to
the following two conditions: (1) this device may not cause harmful
interference, and (2) this device must accept any interference received,
including interference that may cause undesired operation.
NOTE : The manufacturer is not responsible for any radio or TV
interference caused by unauthorized modifications or changes to this
equipment. Such modifications or changes could void the user’s authority to
operate the equipment.
NOTE : This equipment has been tested and found to comply with the limits
for a Class B digital device, pursuant to part 15 of the FCC Rules. These
limits are designed to provide reasonable protection against harmful
interference in a residential installation. This equipment generates uses and
can radiate radio frequency energy and, if not installed and used in
accordance with the instructions, may cause harmful interference to radio
communications. However, there is no guarantee that interference will not
occur in a particular installation. If this equipment does cause harmful
interference to radio or television reception, which can be determined by
turning the equipment off and on, the user is encouraged to try to correct the
interference by one or more of the following measures:
- Reorient or relocate the receiving antenna.
- Increase the separation between the equipment and receiver.
- Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
- Consult the dealer or an experienced radio/TV technician for help.
FCC Caution: Any changes or modifications not expressly approved by the party responsible for compliance could void the user’s authority to operate this equipment.
ORIGINAL EQUIPMENT MANUFACTURER (OEM) NOTES
The OEM must certify the final end product to comply with unintentional
radiators (FCC Sections 15.107 and 15.109) before declaring compliance of the
final product to Part 15 of the FCC rules and regulations. Integration into
devices that are directly or indirectly connected to AC lines must add with
Class II Permissive Change.
The OEM must comply with the FCC labeling requirements. If the module’s label
is not visible when installed, then an additional permanent label must be
applied on the outside of the finished product which states: “Contains
transmitter module FCC
ID: 2AOFDL-LRNTB25. Additionally, the following statement should be included
on the label and in the final product’s user manual: “This device complies
with Part 15 of the FCC Rules. Operation is subject to the following two
conditions:
(1) This device may not cause harmful interferences, and
(2) this device must accept any interference received, including interference
that may cause undesired operation.”
The module is allowed to be installed in mobile and portable applications A module or modules can only be used without additional authorizations if they have been tested and granted under the same intended end‐use operational conditions, including simultaneous transmission operations. When they have not been tested and granted in this manner, additional testing and/or FCC application filing may be required. The most straightforward approach to address additional testing conditions is to have the grantee responsible for the certification of at least one of the modules submit a permissive change application. When having a module grantee file a permissive change is not practical or feasible, the following guidance provides some additional options for host manufacturers. Integrations using modules where additional testing and/or FCC application filing(s) may be required are: (A) a module used in devices requiring additional RF exposure compliance information (e.g., MPE evaluation or SAR testing); (B) limited and/or split modules not meeting all of the module requirements; and (C) simultaneous transmissions for independent collocated transmitters not previously granted together.
This Module is full modular approval, it is limited to OEM installation ONLY. Integration into devices that are directly or indirectly connected to AC lines must add with Class II Permissive Change. (OEM) Integrator has to assure compliance of the entire end product include the integrated Module. Additional measurements (15B) and/or equipment authorizations(e.g. Verification) may need to be addressed depending on co-location or simultaneous transmission issues if applicable.(OEM) Integrator is reminded to assure that these installation instructions will not be made available to the end user.