Lierda FL22-C8 User manual

FL22-C8
LoRa 868/915MHz SPI Passive crystal standard modules
The FL22-C8 is a new generation of LORA spread spectrum RF transceiver module from Lierda Technology
Group, with smaller size, lower power consumption and higher transmitting power. Based on SEMTECH's RF
integrated chip LLCC68 development block. It is a high-performance IoT wireless transceiver, and its special LoRa
debugging method can greatly increase the communication distance, which can be widely used in various
occasions in the field of short-range IoT wireless communication. It has the characteristics of small size, low power
consumption, long transmission distance and strong anti-interference ability, etc. A variety of antenna solutions
are available according to the actual application, and the module is not equipped with a micro-control chip, which
is mainly used for secondary development by customers.
Product features
·Operating frequency band
- Operating frequency band 860-930MHz
（902.3-924.9MHZ for FCC application）
·Multiple modulation options
- Supports LoRa,GFSK, FSK and other
modulation methods
·Ultra-low power consumption
-Supports 1.8V to 3.7V power supply (transmit
power at +18dBm configuration, must not fall
below 3.1V)
-Transmit current ≤ 125mA (maximum transmit
power configuration)
-Receive current ≤ 6.5mA (DC-DC mode)
-600uA standby current
-600nA sleep current (register value saved)
·High Link Budget
-Sensitivity -124dBm±1dBm (SF=7,
BW_L=125KHz)
-Transmit power Max. 18 dBm
·Size
- 18.4*18.4*3.0mm
·Ultra-long transmission range
- 6Km@250bps (urban environment, LoRa
modulation, maximum transmitting power)
·High confidentiality
- Using LoRa modulation, which cannot be
captured and parsed by conventional wireless
devices
·Communication interface
-SPI communication interface, can be directly
connected to various microcontrollers, software
programming is very convenient
Applicable scenarios
-Automated Building Circulation System
-Smart Home
-Temperature and humidity sensors
-Wireless remote control, drones
-For applications requiring high communication
distance

Lierda provides this document to support its customers in the design of their products.
Customers are required to design their products in accordance with the specifications and
parameters provided in the document. The company is not responsible for any personal injury
or property damage caused by improper handling by the customer. Lierda reserves the right to
update this document without prior notice.
Copyright this document is the copyright of Lierda Corporation and anyone who reproduces
this document without our permission will be held liable.
Copyright © Lierda Technology Group, all rights reserved.Copyright © Lierda Science &
Technology Group Co.,Ltd
Document revision history
Version
Date
Change description
Rev01 2021-03-31 Initial version
Rev02 2021-04-21 Add packet length parameter table
Rev03 2021-09-09 Add EU regional parameter description
Rev04 2022-05-31 Revised product name
1Specification
Table 1-1 Module limit parameters
Performance
Main parameters
Remarks
Minimum value
Maximum value
Supply voltage (V) -0.5 +3.9
Maximum RF input power (dBm) -+10
Operating temperature (°C) -40 +85
Table 1-2 Module operating parameters 1
1
1, the above test conditions are, temperature: 25 ℃, centre frequency: 915MHz, operating voltage: 3.3V
2, the output power must be set in accordance with the optimization recommendations, if the settings do not match the
recommended value, the power and power consumption may not be excellent, or even damage to the module, see Table 1-3 &
Table 1-4 for configuration.
Performance
Main parameters
Minimum
value
Typical
values
Maximum
value
Remarks

Operating voltage (V)
1.8
3.3
3.7
Operating temperature
(°C)
-40 -85
Initial frequency
offset (KHz)
-11 -+11
Operating Frequency
Band (MHz)
860
902.3-924.9MHz for FCC
930
application
Emission
90 110 125 DC-DC Mode，18dBm transmit
status
-
50
DC-DC Mode，EU868，max14dBm
60
(mA) transmit
Power
consumption
Receiving
status
(mA)
- 5.5 6.5
DC-DC Mode，Rx Boosted
BW_L=125kHz
Sleep
state
(uA)
- 0.6 2 Register value storage
Transmit power (dBm) 17 18 -
Setting the actual output at
maximum output power
Reception sensitivity
(dBm)
- -124 - BW_L=125KHz,SF=7
Communication
Rate
LoRa
（bps）
FSK
（bps）
- - 62.5K
- - 150K
User programmable
customisation
User programmable
customisation
Modulation method LoRa/GFSK/FSK
User programmable
customisation
Interface type Stamp hole 2 mm Spacing
Communication
protocols
Dimensions (mm)
SPI
18.4*18.4*3.0mm（Figure 2-1 for
details）
SPI communication allows a
maximum rate of 16MHz
-
Dimensional accuracy Level GB/T1804-C
Meets dimensional tolerance
class C requirements

Table 1-3 PA operating mode optimisation settings I
Output power
(dBm)
paDutyCycle
hpMax
deviceSel
paLut
Value in
SetTxParams
18
0x04
0x07
0x00
0x01
22
Note: For example, 915MHz, maximum 18dBm power, when using, you can go to the configuration to change the
SetTxParams parameter value size to change the actual output power size, the maximum value is 22.
Table 1-4 PA operating mode optimisation settings II
Output power
(dBm)
paDutyCycle
hpMax
deviceSel
paLut
Value in
SetTxParams
14
0x02
0x02
0x00
0x01
21
Note: If 868MHz, 14dBm power is used, the SetTxParams parameter can be configured to change the actual output
power.
2Dimensional drawings and pin definitions
2.1 Dimensional drawings Unit: mm
Figure 2-1 Dimensional drawing of FL22-22
2.3 Pin definitions
Table 2-1 Pin definitions
PIN
Interface name
Function
P1 NRESET Reset pin, active low

P2
DIO1 Interrupt source mapping pins (see LLCC68 datasheet
for details)
P3
DIO2 Interrupt source mapping pins (see LLCC68 datasheet
for details)
P4 BUSY Line Occupancy Indicator
P5
SW_CTL2 RF switch control pin 2,TX：SW_CTL1=0，SW_CTL2=1
RX：SW_CTL1=1，SW_CTL2=0
Sleep：
SW_CTL1=0
，
SW_CTL2=0
P6
SW_CTL1 RF switch control pin 1，TX：SW_CTL1=0，SW_CTL2=1
RX：SW_CTL1=1，SW_CTL2=0
Sleep：SW_CTL1=0，SW_CTL2=0
P7 GND Power ground
P8 VCC Power supply VCC
P9 MISO SPI data output
P10 MOSI SPI data input
P11 NSS Chip SPI enable
P12 SCK SPI clock input
P13 GND Power ground
P14 RF RF output
3Basic operation
3.1 Packet size selection
The maximum packet byte setting can support 255 bytes. Considering the actual usage, a packet
with a larger number of bytes will last longer in the air and be susceptible to interference,
especially at low rates which may have a greater impact, and this module may even fail to
communicat
Table 3-1 FL22-22 LoRa mode supported rate configuration and recommended maximum packet length

BW
PL2
SF
125kHz
5 255 bytes（136ms
）
6 255 bytes（229ms
）
7 255 bytes（394ms
）
8 255 bytes（696ms
）
9
255 bytes
（1250ms
）
10
Not supported
11
Not supported
12
Not supported
3.2 Hardware layout considerations
1. 1. DIO port as far as possible to connect to the MCU with external interrupt IOport.
2. 2. The RF exit to the antenna pad part of the alignment as short as possible, to go 50Ω impedance
line, and need to wrap the ground, the alignment around the more perforated.
3. 3. If possible, add π circuitry from the RF exit to the antenna pad.
4. 4. The antenna should be surrounded by clear space, leaving at least 5mm of clear space.5.
5. 5. Pay attention to a good amount of grounding, preferably ensure a large area of grounding.
6. 6. Keep away from high voltage circuits, high frequency switching circuits.
7. can refer to the application document "RF PCB LAYOUT design rules (for sub-1GHZ and
Bluetooth modules)" for layout and routing.
3.3 Software operation
By inserting the module on the user's board, using the microcontroller to communicate
with the module via SPI, and manipulating its registers and transceiver cache via API commands,
the wireless data transmission and reception function can be completed. Please refer to the
latest LLCC68 data sheet for the timing of the module register read/write operations.
The API instructions are detailed in the LLCC68 datasheet and the corresponding API instruction
functions are provided in the Lierda demo routines.
4Frequently Asked Questions
4.1 Modules cannot communicate even at close range
· Confirm that the configuration of the transmit and receive sides do not match, different
configurations do not communicate properly.
· Voltages are abnormal, low voltages can lead to transmission abnormalities.
· Low battery, low battery voltage will be pulled down when transmitting causing a
PL indicates the recommended maximum packet length or the time required to transmit the next packet of that packet length (calculated as CR=4/5, Preamble length is
8 symbol); "not supported" means that the LLCC68 chip itself does not support this configuration.

transmission abnormality.
·Antenna soldering abnormality RF signal is not reaching the antenna or πcircuit is
soldered incorrectly.
4.2 Module power consumption anomaly
·The module is damaged due to static electricity, etc., resulting in abnormal power
consumption.
·hen doing low-power reception, incorrect timing configuration etc. leads to module power
consumption does not achieve the expected effect.
·Individually measured module or MCU are normal, the power consumption abnormalities appear
in the joint tuning is due to the MCU and RF module connection pins are not handled properly.
·The working environment is harsh, in high temperature, high humidity, low temperature and
other extreme environment module power consumption will fluctuate.
4.3 Insufficient module communication distance
·The antenna impedance is not matched properly resulting in low power being transmitted.
· There are objects such as metal around the antenna or the module is inside metal causing
severe signal attenuation.
· There are other interfering signals in the test environment causing the module to
communicate at a close distance.
· Insufficient power supply causes the module to transmit at an abnormal power level.
· The test environment is harsh and the signal attenuation is high.
·Module through the wall and other environments and then communicate with the other end,
the wall, etc. on the signal attenuation is very large, most of the signal is bypassed
through the wall signal attenuation is large.
·The module is too close to the ground is absorbed and reflected resulting in poor
communication.

Caution
Any Changes or modifications not expressly approved by the party responsible for compliance could
void the user’s authority to operate the equipment.
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: 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.
RF Exposure Statement
This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment.
This equipment should be installed and operated with minimum distance 20cm between the radiator and
your body.
FCC Label Instructions
If using a permanently affixed label, the modular transmitter must be labeled with its own FCC
identification number, and, if the FCC or IESD identification number is not visible when the module is
installed inside another device, then the outside of the device into which the module is installed must also
display a label referring to the enclosed module. This exterior label can use wording such as the following:
“Contains FCC ID: 2AOFDFL22-C8”.
Any similar wording that expresses the same meaning may be used. The Grantee may either provide
such a label, an example of which must be included in the application for equipment authorization, or,
must provide adequate instructions along with the module which explain this requirement.

OEM Guidance
1. Applicable FCC rules
This device complies with part 15.247 of the FCC Rules.
2. The specific operational use conditions
This module can be used in IoT devices. The input voltage to the module is
nominally 3.3 V DC. The operational ambient temperature of the module is
-40 °C ~ 85 °C. the external antenna is allowed, such as dipole antenna.
3. Limited module procedures
N/A
4. Trace antenna design
N/A
5. RF exposure considerations
The equipment complies with FCC radiation exposure limits set forth for an
uncontrolled environment. This equipment should be installed and operated with
minimum distance 20cm between the radiator and your body. If the equipment
built into a host as a portable usage, the additional RF exposure evaluation may
be required as specified by 2.1093.
6. Antenna
Antenna type: Dipole antenna; Peak antenna gain : 2 dBi
7. Label and compliance information
An exterior label on OEM’s end product can use wording such as the
following: “Contains Transmitter Module FCC ID: 2AOFDFL22-C8”
or “Contains FCC ID: 2AOFDFL22-C8”
8. Information on test modes and additional testing requirements
a) The modular transmitter has been fully tested by the module grantee on the required
number of channels,modulation types, and modes, it should not be necessary for the host
installer to re-test all the available transmitter modes or settings. It is recommended that the
host product manufacturer, installing the modular transmitter,perform some investigative
measurements to confirm that the resulting composite system does not exceed the spurious
emissions limits or band edge limits (e.g., where a different antenna may be causing
additional emissions).
b) The testing should check for emissions that may occur due to the intermixing of emissions
with the other transmitters, digital circuitry, or due to physical properties of the host product
(enclosure). This investigation is especially important when integrating multiple modular
transmitters where the certification is based on testing each of them in a stand-alone
configuration. It is important to note that host product manufacturers should not assume that
because the modular transmitter is certified that they do not have any responsibility for final
product compliance.
c) If the investigation indicates a compliance concern the host product manufacturer is
obligated to mitigate the issue. Host products using a modular transmitter are subject to all
the applicable individual technical rules as well as to the general conditions of operation in
Sections 15.5, 15.15, and 15.29 to not cause interference. The operator of the host product
will be obligated to stop operating the device until the interference have been corrected .
9. Additional testing, Part 15 Sub part B disclaimer The final host / module combination
need to be evaluated against the FCC Part 15B criteria for unintentional radiators in order
to be properly authorized for operation as a Part 15 digital device.

The host integrator installing this module into their product must ensure that the final
composite product complies with the FCC requirements by a technical assessment or
evaluation to the FCC rules, including the transmitter operation and should refer to guidance
in KDB 996369. For host products with certified modular transmitter, the frequency range of
investigation of the composite system is specified by rule in Sections 15.33(a)(1) through
(a)(3), or the range applicable to the digital device, as shown in Section 15.33(b)(1),
whichever is the higher frequency range of investigation
When testing the host product, all the transmitters must be operating.The transmitters can
be enabled by using publicly-available drivers and turned on, so the transmitters are active.
In certain conditions it might be appropriate to use a technology-specific call box (test set)
where accessory 50 devices or drivers are not available. When testing for emissions from
the unintentional radiator, the transmitter shall be placed in the receive mode or idle mode, if
possible. If receive mode only is not possible then, the radio shall be passive (preferred)
and/or active scanning. In these cases, this would need to enable activity on the
communication BUS (i.e., PCIe, SDIO, USB) to ensure the unintentional radiator circuitry is
enabled. Testing laboratories may need to add attenuation or filters depending on the signal
strength of any active beacons (if applicable) from the enabled radio(s). See ANSI C63.4,
ANSI C63.10 and ANSI C63.26 for further general testing details.
The product under test is set into a link/association with a partnering device, as per the
normal intended use of the product. To ease testing, the product under test is set to transmit
at a high duty cycle, such as by sending a file or streaming some media conte
nt.