Ebyte E28-2G4T27SX User manual

E28-2G4T27SX
SX1280 2.4GHz LoRa Module

Chengdu Ebyte Electronic Technology Co.,Ltd. E28-2G4T27SX User Manual
Copyright ©2012–2020, Chengdu Ebyte Electronic Technology Co., Ltd.
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Contents
Contents ····················································································································································································································································1
1.Product Overview......................................................................................................................................................................................................3
1.1 Brief Introduction........................................................................................................................................................................................... 3
1.3 Application..................................................................................................................................................................................................... 3
2. Technical Parameters................................................................................................................................................................................................4
2.1 Limit parameter.............................................................................................................................................................................................. 4
2.2 Operating parameter....................................................................................................................................................................................... 4
3. Mechanical Characteristics.......................................................................................................................................................................................5
3.1. Dimension Plan............................................................................................................................................................................................. 5
3.2. Pin Definition................................................................................................................................................................................................ 6
4. Recommended Connection Diagram........................................................................................................................................................................7
5. Functional Description............................................................................................................................................................................................. 7
5.1. Fixed Transmission....................................................................................................................................................................................... 7
5.2. Broadcast....................................................................................................................................................................................................... 8
5.3. Broadcast Address......................................................................................................................................................................................... 8
5.4. Monitor Address............................................................................................................................................................................................8
5.5. Module Reset.................................................................................................................................................................................................8
5.6. AUX Description...........................................................................................................................................................................................8
5.6.1 Indication of serial output....................................................................................................................................................................8
5.6.2 Indication of wireless transmission..................................................................................................................................................... 9
5.6.3 Module in configuration process......................................................................................................................................................... 9
6. Operation Modes...................................................................................................................................................................................................... 9
6.1. Mode Switch..................................................................................................................................................................................................9
6.2. Transmission Mode (Mode 0)..................................................................................................................................................................... 10
6.3. RSSI Mode (Mode 1).................................................................................................................................................................................. 10
6.4. Ranging Mode (Mode 2)............................................................................................................................................................................. 10
6.5. Configuration mode (Mode 3).....................................................................................................................................................................10
7. Command Format...................................................................................................................................................................................................11
7.1. Default parameter values.............................................................................................................................................................................11
7.2. Reading Operating Parameters.................................................................................................................................................................... 11
7.3. Reading Version Number............................................................................................................................................................................ 11
7.4. Reset Command...........................................................................................................................................................................................12
7.5. Parameter Configuration Commands.......................................................................................................................................................... 12
8. Hardware design.....................................................................................................................................................................................................14
9. FAQ........................................................................................................................................................................................................................ 15
9.1 Communication range is too short.............................................................................................................................................................15
9.2 Module is easy to damage........................................................................................................................................................................... 15
9.3 BER(Bit Error Rate) is high......................................................................................................................................................................... 15
10.Production Guidance............................................................................................................................................................................................. 16
10.1 Reflow soldering temperature.................................................................................................................................................................... 16
10.2. Reflow soldering curve..............................................................................................................................................................................16
11. Related products................................................................................................................................................................................................... 17
12. Antenna Guidance................................................................................................................................................................................................ 18
13. Package for batch order........................................................................................................................................................................................ 19
Revision history..........................................................................................................................................................................................................19

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Copyright ©2012–2020, Chengdu Ebyte Electronic Technology Co., Ltd.
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About us......................................................................................................................................................................................................................19

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1.Product Overview
1.1 Brief Introduction
E28-2G4T27SX is an UART module based on SEMTECH SX1281, it adopts
transparent transmission and works at 2.4GHz band. It adopts LoRa, FLRC and
GFSK modulations. It features SMD packing with both IPX and PCB antenna
interfaces, compatible with 3.3V and 5V IO port voltage.
The LoRa direct sequence spread spectrum (DSSS) enables longer
communication range and better anti-interference ability. The forward error
correction (FEC) algorism enables better coding efficiency and error correction
ability. The module will proactively correct the interfered data packets when
sudden interference occurs, which significantly improves the communication range and reliability.
Antenna is optional (IPEX / stamp hole), which is convenient for user's secondary development and integration.
1.2 Features
Support various modulation such as GFSK Mode，FLRC Mode，LoRa Mode;
Supporting high-speed continuous transmission, data without subcontracting;
Support RSSI for evaluating signal quality；
Supports air wake-up, low power consumption,suitable for battery power supply solution;
Support fixed transmission/broadcast/monitoring；
Communication distance tested is up to 5km in ideal condition;；
Maximum transmitting power of 27dBm, Software adjustable；
Support the global license-free ISM 2.4GHz；
Support air data rate of 1kbps～2Mbps;
Low power consumption for battery supplied applications；
Support 2.3V~5.5V power supply, power supply over 5.5V can guarantee the best performance；
Industrial grade standard design, support -40 ~ 85 °C for working over a long time；
1.3Application
Smart Home and Industrial Sensors;
Security system, location System
Wireless remote control; UAV；
Wireless Game Remote Controller
Health care products；
Wireless voice, wireless headset;
Automotive industry applications.

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2. Technical Parameters
2.1 Limit parameter
Main parameter
Performance
Note
Min
Max
Voltage supply [V]
2.3
5.5
Voltage over 5.5V will cause permanent damage to
module
Blocking power [dBm]
-
10
Chances of burn is slim when modules are used in
short distance
Operating temperature [℃]
-40
+85
-
2.2 Operating parameter
Main parameter
Performance
Note
Min
Typ
Max
Voltage supply [V]
2.3
5.0
5.5
≥5.0V ensures output power
Communication level [V]
-
3.3
-
For 5V TTL, it may be at risk of burning down
Operating temperature [℃]
-40
-
+85
-
Frequency [MHz]
2400
-
2500
ISM band
Power
consumption
Transmitting current
[mA]
-
500
-
Instant power consumption
Receiving current
[mA]
-
27
-
-
Turn-off current
[μA]
-
10
-
Software is shut down
Transmitting power [dBm]
26.5
27
27.5
Receiving sensitivity [dBm]
-130
-132
-134
Air data rate: 115.2Kbps
Air data rate（bps）
1k
1k
2M
Defined by user via programming
Main parameter
Description
Note
Distance
5000m
Test condition：clear and open area, antenna gain: 5dBi，antenna
height: 2.5m，air data rate: 1kbps
FIFO
121 Btye
Max. Transmitting length per packet
221 Btye
Continuous transmission mode
Cache
2048 Byte
-
Modulation
GFSK
-
LoRa
-
FLRC
-
Interface
UART
TTL
Package
SMD
-
Connector
1.27mm
-

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Size
40.5*25mm
-
Antenna
IPEX/Sample
hole
50Ω Impedance
3. Mechanical Characteristics
3.1. Dimension Plan

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3.2. Pin Definition
Pin No.
Pin Name
Pin Direction
Function
1
GND
Ground
Ground
2
NC
-
cannot be floated, can be grounded if not used
3
NC
-
cannot be floated, can be grounded if not used
4
NC
-
cannot be floated, can be grounded if not used
5
NC
-
cannot be floated, can be grounded if not used
6
NC
-
cannot be floated, can be grounded if not used
7
NC
-
cannot be floated, can be grounded if not used
8
GND
Ground
Ground
9
NC
-
cannot be floated, can be grounded if not used
10
GND
Ground
Ground
11
VCC
-
Module power source positive reference.
Voltage range: 2.5V ~ 5.5V DC
12
AUX
Input
Used to indicate the module operation status, when user wakes up the
external MCU,it outputs low level during initialization after power on
and self-check, can be configured as open-drain output or push-pull
output, please refer to Parameter Configuration.
(can be floated)
13
TXD
Output
TTL serial input, connected to external TXD output pin. Can be
configured as open-drain or pull-up input, please refer to Parameter
Configuration.
14
RXD
Output
TTL serial input, connected to external TXD output pin;
It can be configured as drain open circuit or pull-up input. See parameter
setting for details
15
M1
Input
M2、M1、M0 共同组合决定模块 8种工作模式
M2, M1 and M0 determine eight working modes
16
M0
Input
M2, M1 and M0 determine eight working modes
17
M2
Input
M2, M1 and M0 determine eight working modes
18
GND
Ground
Ground
19
ANT
-
Antenna interface (50 Ω characteristic impedance)
20
GND
Ground
Ground
21
GND
Ground
Ground
22
NC
-
cannot be floated, can be grounded if not used

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4. Recommended Connection Diagram
5. Functional Description
5.1. Fixed Transmission
No.
Brief description for module-MCU connection (STM8L MCU as example)
1
The wireless UART module adopts TTL level, please connect to MCU with TTL level.
2
For some 5V MCU, 4~10K pull-up resistor may need to be added at the TXD and AUX pins of the module.

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5.2. Broadcast
5.3. Broadcast Address
i.e.: set the address of module A as 0xFFFF or 0x0000 and channel as 0x04.
When set A as transmitter (same mode, transparent transmission on), all modules with channel 0x04 will receive broadcast
data.
5.4. Monitor Address
i.,e.: set the address of module A as 0xFFFF or 0x0000 and channel as 0x04.
When set A as receiver, it will receive the data transmitted by modules with channel 0x04.
5.5. Module Reset
When the module is powered on, the AUX output will go to a low level immediately, the module conducts hardware
self-check and sets the operating mode on the basis of the user parameters (M0 M1). During the process, the AUX level
remains low. After the process completed, the AUX outputs high a level and starts to work as per the operating mode
indicated by the combined state of M1 and M0. The user needs to wait until the AUX rising edge is high, indicating the
module is ready for normal work.
5.6. AUX Description
AUX Pin can be used as indication for wireless send & receive buffer and self-check. It can indicate whether there is data
that is yet to send via wireless or whether all wireless data has been sent through UART, or whether the module is still in the
process of self-check initialization.
5.6.1 Indication of serial output
Used to wake up the external MCU (note: AUX indicates no delay under continuous mode)

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5.6.2 Indication of wireless transmission
Under sub-packet transmission mode, the internal buffer size is determined by the sub-packet size, if the packet length is 221
bytes, then the buffer size will be 2048 bytes, when AUX=1, user could continuously initiate transmitting of no more than
2048 bytes.
Under continuous transmission mode, AUX=1 means the module is busy, but it is not applicable for waking up external
MCU, because the data transmission is very quick under continuous transmission mode.
AUX=1 means all serial data is transmitted through RF, and the module is at idle state.
5.6.3 Module in configuration process
Only occurs when resetting or when exiting sleep mode
6. Operation Modes
The module has 4 operation modes, which are determined accordingly by pins M0, M1. Please refer to below instructions:
6.1. Mode Switch
User could determine the module operation mode through the combination of high-low level of M2, M1 and M0. Mode
switch can be controlled through the GPIO of the MCU.
When M2, M1 and M0 changed and the module is in idle state (AUX at high level), it can starts to work normally under new
Mode（0-3）
M2
M1
M0
Introduction
Remarks
0 - Transmission Mode
1
0
0
Serial port on, RF on, continuous
transparent transmission
The air data rate can be manually configured and
automatically adjusted along with baud rate values；
the baud rates on both sides must be the same under
continuous transmission mode
1 - RSSI Mode
1
0
1
Serial port on, RF on, RSSI on
The module outputs RSSI value through serial port
every 100ms
2 – Ranging Mode
1
1
0
Reserved
-
3 - Configuration
Mode
1
1
1
Serial port on ，RF off, parameter
configuration
Baud rate is fixed as 9600 8N1
4 -Low power
0
x
x
lowest power consumption in low power
mode
When M2 is set high, it is in normal working
condition.
when M2 is set low, it is in low power mode

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mode, if serial data not transmitted completely, it will enter new mode after all data is transmitted; if the module receives
data and send out through serial port, the module will enter new mode after the data is transmitted completely; so mode
switch will only be valid when AUX outputs 1, or switch will be delayed.
i.e.: under mode 2 or mode 4, when user inputs large amount of data continuously and conducts mode switch, the mode
switch is invalid; the module will conduct new mode check after all data is transmitted; so, users are recommended to check
the AUX pin status and conduct mode switch 2ms later when AUX outputs high level.
When the module enters configuration mode from other modes, it will enter sleep mode when all data is processed
completely (both TX and RX). This feature can be used for quick sleep to save energy; i.e.: the transmitter works under mode
0 and the user send serial data“12345”, then the user does not need to wait till the AUX enters idle state (high level) and
directly switches to sleep mode and put the user main MCU into sleep mode, the module will automatically enter sleep mode
1ms later when all data is processed so as to save the MCU working time and lower energy consumption.
Similarly, this feature can be utilized for any mode switch, the module will enter new mode automatically within 1ms when
current even is processed completely, which saves the user’s efforts in checking AUX status and enables quick mode switch;
for example, when switching from transmitting mode to receiving mode, the user MCU could enter sleep mode before mode
switch, mode switch can be made by acquiring AUX change with external interrupt function.
This operation is very flexible and efficient, it is designed based on convenient MCU operation, and it could ease the
operation load of the entire system and increase the operation efficiency and lower the energy consumption.
6.2. Transmission Mode (Mode 0)
Under this mode, transparent transmission is available, that means the data transmitted from the transmitter will be received
by the receiver in the original format. Under normal mode, the two sides could communicate with each other normally based
on same air data rate, address and channel; under continuous transmission mode, the baud rates on both sides must be the
same, it supports large file continuous transmission under baud rate from 1200bps ~ 115200bps.
6.3. RSSI Mode (Mode 1)
Under this mode, the module will output current RSSI value of 2.4GHz signal every 100ms so as to check the channel quality,
the value is in HEX compliment format.
6.4. Ranging Mode (Mode 2)
(Reserved)
6.5. Configuration mode (Mode 3)
Under this mode, Baud rate is fixed as 9600 8N1

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7. Command Format
Under configuration mode (Mode 3:M0=1, M1=1, M2 =1), the supported parameters are as below
(Only support 9600 and 8N1 format when setting)
No.
Command
Format
Description
1
C0 + working
parameters
C0 + 5 bytes working parameters are sent in hexadecimal format. 6 bytes in total and must be sent in
succession.
(Save the parameters when power-down)
2
C1+C1+C1
Three C1 are sent in hexadecimal format. The module returns the saved parameters and must be sent in
succession.
3
C2 + working
parameters
C2 + 5 bytes working parameters are sent in hexadecimal format. 6 bytes in total and must be sent in
succession. (Do not save the parameters when power-down)
4
C3+C3+C3
Three C3 are sent in hexadecimal format. The module returns the version information and they must be
sent in succession.
5
C4+C4+C4
Three C4 are sent in hexadecimal format. The module will reset one time and they must be sent in
succession.
6
E2+E2+E2
Under transparent transmission mode, send three E2 in HEX format, the module will enter a 10s
parameter configuration window period, user could configure the module parameters in the 10s with C0
command, 10s later, the module will work with the new parameters.
7
E3+E3+E3
Under transparent transmission mode, send three E3 in HEX format, the module will enter a 10s
parameter configuration window period, user could configure the module parameters in the 10s with
6-byte C0 command, 10s later, the module will work with the new parameters.
7.1. Default parameter values
Model
Default parameter values：
Model
Frequency
Address
Channel
Air data rate
Baud rate
Parity
Transmitting
power
E28-2G4T27SX
2.4GHz
0x0000
0x13
10kbps
9600
8N1
27dbm
7.2. Reading Operating Parameters
Command Format
Description
C1+C1+C1
Under configuration,(M0=1,M1=1), send command (HEX format) to the serial: C1 C1 C1, the
module will return current parameter values, i.e.: C0 00 00 13 18 04.
7.3. Reading Version Number
Command Format
Description
C3+C3+C3
Under configuration mode (M0=0, M1=1, M2 =0), send command (HEX format) to the serial:
C3 C3 C3, the module will return current parameter values, i.e.: C3 00 28 10 0C 09 01 00;
The 00 28 means the module model number (E28 series), 10 means the version number, 0C
means the transmitting power, other values means other characteristics.

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7.4. Reset Command
Command Format
Description
C4+C4+C4
Under configuration mode (M0=0, M1=1, M2 =0), send command (HEX format) to the serial: C4 C4 C4, the module
will conduct a reset;
During reset, the module will conduct self-check, AUX outputs low level, when reset is completed, AUX outputs high
level, the module starts to work normally. Now, user could switch mode or send another command.
7.5. Parameter Configuration Commands
No.
Item
Description
Remarks
0
HEAD
Fix 0xC0 or 0xC2, it means this frame data is control command
Must be 0xC0 or 0xC2
C0: Save the parameters when power-down
C2: Do not save the parameters when
power-down
1
ADDH
High address byte of module
（the default 00H）
00H-FFH
2
ADDL
Low address byte of module
（the default 00H）
00H-FFH
3
SPED
7
6
UART parity bit
The serial modes can be different on two
sides;
0
0
8N1（default）
0
1
8O1
1
0
8E1
1
1
8N1（equal to 00）
5
4
3
TTL UART baud rate（bps）
Under normal mode, the mode can be
different；
Under continuous transmission mode, the
baud rate must be the same.
0
0
0
1200
0
0
1
4800
0
1
0
9600（default）
0
1
1
19200
1
0
0
57600
1
0
1
115200
1
1
0
460800
1
1
1
921600
2
1
0
Air data rate (bps)
Under non-continuous transmission mode,
baud rate has nothing to do with RF
parameters, and will not affect the
transmission characteristics.
Under continuous transmission mode, baud
rate decides the air data rate. The high the
baud rate, the faster the data transmission
and the shorter communication range.
The lower the air data rate, the longer the
transmitting distance, the better
anti-interference performance and the
longer transmitting time.
The air data rates on both sides must be the
same.
0
0
0
Self-adaptive(continuous
transmission)
0
0
1
1k
0
1
0
5k
0
1
1
10k（default）
1
0
0
50k
1
0
1
100k
1
1
0
1M（FLRC）
1
1
1
2M（FSK）

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4
CHAN
Communication Channel
Default: 0x18
Normal mode: When air data rate is 1k, 5k or 10k, the formula to
calculate channel is: 2400 + CHAN * 1MHz; when air data rate is
50k or 100k, the formula to calculate channel is: 2400 + CHAN *
2MHz; when air data rate is 1M, the formula to calculate channel
is: 2400 + CHAN * 3MHz; when air data rate is 2M, the formula
to calculate channel is: 2400 + CHAN * 5MHz;
Continuous transmission mode: When baud rate is 1200, 9600 or
9200, the formula to calculate channel is: 2400 + CHAN *2MHz；
when baud rate is 4800, 57600, 115200, the formula to calculate
channel is: 2400 + CHAN *4MHz; when baud rate is 460800,
921600, the formula to calculate channel is: 2400 + CHAN
*5MHz.
5
OPTION
7
Fixed transmission enabling bit (similar to Modbus)
Under fixed transmission mode, the first
three bytes of each user's data frame can be
used as high/low address and channel. The
module changes its address and channel
when transmit. And it will revert to original
setting after complete the process.
It is transparent transmission under
continuous mode.
0
Transparent transmission mode
1
Fixed transmission mode
6
Reserved
5
Reserved
4
Measuring mode device type (reserved)
Under range measuring mode, the slave
module address is determined by the ADDH
and ADDL.
0
Slave (default)
1
Master
3
LBT switch
When LBT is turned on, channel quality
will be checked before sending every data
packet; if quality is good, data will be sent
directly, if interference exists, data will be
sent after interference disappears.
It supports LBT only below air data rate
115200bps, LBT may affect the continuous
transmission function.
0
Turn off LBT (default)
1
Turn on LBT
2
IO driving mode
This bit is used to the module internal
pull-up resistor. It also increases the level’s
adaptability in case of open drain. But in
some cases, it may need external pull-up
resistor.
1
TXD, AUX push-pull output, RXD pull-up input
0
TXD, AUX open-circuit output, RXD open-circuit
input
1
0
Transmission power (approximated)
The external power source must provide
100mA or above current output and ensure
the power ripple is lower than 100mV.
Low power transmission is not
recommended due to its low power supply
efficiency.
0
0
27dBm（defult））
0
1
23dBm
1
0
20dBm
1
1
17dBm

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8. Hardware design
It is recommended to use a DC stabilized power supply. The power supply ripple factor is as small as possible,
and the module needs to be reliably grounded.；
Please pay attention to the correct connection of the positive and negative poles of the power supply.
Reverse connection may cause permanent damage to the module；
Please check the power supply to ensure it is within the recommended voltage otherwise when it exceeds the
maximum value the module will be permanently damaged；
Please check the stability of the power supply, the voltage can not be fluctuated frequently；
When designing the power supply circuit for the module, it is often recommended to reserve more than 30%
of the margin, so the whole machine is beneficial for long-term stable operation；
The module should be as far away as possible from the power supply, transformers, high-frequency wiring
and other parts with large electromagnetic interference；
High-frequency digital routing, high-frequency analog routing, and power routing must be avoided under
the module. If it is necessary to pass through the module, assume that the module is soldered to the Top
Layer, and the copper is spread on the Top Layer of the module contact part(well grounded), it must be close
to the digital part of the module and routed in the Bottom Layer；
Assuming the module is soldered or placed over the Top Layer, it is wrong to randomly route over the
Bottom Layer or other layers, which will affect the module's spurs and receiving sensitivity to varying
degrees；
It is assumed that there are devices with large electromagnetic interference around the module that will
greatly affect the performance. It is recommended to keep them away from the module according to the
strength of the interference. If necessary, appropriate isolation and shielding can be done；
Assume that there are traces with large electromagnetic interference (high-frequency digital, high-frequency
analog, power traces) around the module that will greatly affect the performance of the module. It is
recommended to stay away from the module according to the strength of the interference.If necessary,
appropriate isolation and shielding can be done.
If the communication line uses a 5V level, a 1k-5.1k resistor must be connected in series (not recommended,
there is still a risk of damage)；
Try to stay away from some physical layers such as TTL protocol at 2.4GHz , for example: USB3.0；
The mounting structure of antenna has a great influence on the performance of the module. It is necessary to
ensure that the antenna is exposed, preferably vertically upward. When the module is mounted inside the
case, use a good antenna extension cable to extend the antenna to the outside；
The antenna must not be installed inside the metal case, which will cause the transmission distance to be
greatly weakened.

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9. FAQ
9.1 Communication range is too short
The communication distance will be affected when obstacle exists.
Data lose rate will be affected by temperature, humidity and co-channel interference.
The ground will absorb and reflect wireless radio wave, so the performance will be poor when testing near ground.
Sea water has great ability in absorbing wireless radio wave, so performance will be poor when testing near the sea.
The signal will be affected when the antenna is near metal object or put in a metal case.
Power register was set incorrectly, air data rate is set as too high (the higher the air data rate, the shorter the distance).
The power supply low voltage under room temperature is lower than 2.5V, the lower the voltage, the lower the
transmitting power.
Due to antenna quality or poor matching between antenna and module.
9.2 Module is easy to damage
Please check the power supply source, ensure it is 2.0V~3.6V, voltage higher than 3.6V will damage the module.
Please check the stability of power source, the voltage cannot fluctuate too much.
Please make sure antistatic measure are taken when installing and using, high frequency devices have electrostatic
susceptibility.
Please ensure the humidity is within limited range, some parts are sensitive to humidity.
9.3 BER(Bit Error Rate) is high
There are co-channel signal interference nearby, please be away from interference sources or modify frequency and channel
to avoid interference;
Poor power supply may cause messy code. Make sure that the power supply is reliable.
The extension line and feeder quality are poor or too long, so the bit error rate is high

Chengdu Ebyte Electronic Technology Co.,Ltd. E28-2G4T27SX User Manual
Copyright ©2012–2020, Chengdu Ebyte Electronic Technology Co., Ltd.
16
10. Production Guidance
10.1 Reflow soldering temperature
Profile Feature
Curve characteristics
Sn-Pb Assembly
Pb-Free Assembly
Solder Paste
Solder Paste
Sn63/Pb37
Sn96.5/Ag3/Cu0.5
Preheat Temperature min （Tsmin）
Min preheating temp.
100℃
150℃
Preheat temperature max (Tsmax)
Max preheating temp.
150℃
200℃
Preheat Time (Tsmin to Tsmax)(ts)
Preheating time
60-120 sec
60-120 sec
Average ramp-up rate(Tsmax to Tp)
Average ramp-up rate
3℃/second max
3℃/second max
Liquidous Temperature (TL)
Liquid phase temp.
183℃
217℃
Time（tL）Maintained Above（TL）
Time above liquid phase line
60-90 sec
30-90 sec
Peak temperature（Tp）
Peak temperature
220-235℃
230-250℃
Average ramp-down rate（Tp to Tsmax）
Average ramp-down rate
6℃/second max
6℃/second max
10.2 Reflow soldering curve

Chengdu Ebyte Electronic Technology Co.,Ltd. E28-2G4T27SX User Manual
Copyright ©2012–2020, Chengdu Ebyte Electronic Technology Co., Ltd.
17
11.Related products
Type
IC
Frequency
Power
Distance
Size
Package
Interface
Hz
dBm
km
mm
E28-2G4T27SX
SX1280
2.4G
12.5
3
17.5*28.7
SMD
TTL
E28-2G4M27S
SX1280
2.4G
27
8
15*26.5
SMD
SPI
E28-2G4M20S
SX1280
2.4G
20
6
15*26.5
SMD
SPI
E28-2G4M12S
SX1280
2.4G
12.5
3
25*14
SMD
SPI

Chengdu Ebyte Electronic Technology Co.,Ltd. E28-2G4T27SX User Manual
Copyright ©2012–2020, Chengdu Ebyte Electronic Technology Co., Ltd.
18
12. Antenna Guidance
Antenna plays an important role in the communication process. Inferior antennas often have a great impact on the
communication system. Therefore, we recommend some antennas that support our wireless modules and have excellent
performance and reasonable price.
Model
Type
Frequency
Gain
Size
Feeder
Interface
Feature
Hz
dBi
mm
cm
TX2400-NP-5010
FPC
2.4G
2.0
10x50
-
IPEX
FPC antenna
TX2400-JZ-3
Rubber
2.4G
2.0
30
-
SMA-J
Straight antenna,ultra short
TX2400-JZ-5
Rubber
2.4G
2.0
50
-
SMA-J
Straight antenna,ultra short
TX2400-JW-5
Rubber
2.4G
2.0
50
-
SMA-J
Fixed bending antenna
TX2400-JK-11
Rubber
2.4G
2.5
110
-
SMA-J
Flexible antenna, omnidirectional
TX2400-JK-20
Rubber
2.4G
3.0
200
-
SMA-J
Flexible antenna, omnidirectional
TX2400-XPL-150
Sucker
2.4G
3.5
150
150
SMA-J
Small sucker antenna,high gain

Chengdu Ebyte Electronic Technology Co.,Ltd. E28-2G4T27SX User Manual
Copyright ©2012–2020, Chengdu Ebyte Electronic Technology Co., Ltd.
19
13. Package for batch order
Revision history
Version
Date
Description
Operator
1.0
2020-8-19
Initial Version
Li
About us
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Documents and RF Setting download link: www.ebyte.com
Thank you for using Ebyte products! Please contact us with any questions or suggestions: [email protected]
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Address: B5 Mould Industrial Park, 199# Xiqu Ave, High tech Zone, Chengdu, Sichuan, China