Ebyte E30-TTL-100 User manual

SI4438 Wireless Module
E30 Series
This manual may be modified based on product upgrade, please refer to the latest version.
All rights to interpret and modify this manual belong to Chengdu Ebyte Electronic Technology Co., Ltd.
User Manual

SI4438 Wireless Module User Manual of E30 Series Modules
Copyright ©2012–2017, Chengdu Ebyte Electronic Technology Co., Ltd. 2/17
Version
Date
Description
Issued by
1.00
2017/11/17
Initial version
huaa
Brief Introduction
E30 series wireless transceiver modules, operating at 425-450.5MHz (default: 433MHz) are based on originally imported SI4438
from Silicon Labs, with transparent transmission available, TTL level, WOR (ultra-low power consumption). They feature half duplex and
two kinds of interface: SMD and DIP.
The module has the function of data encryption & compression. The data of the module transmitted over the air features
randomness. With the rigorous encryption & decryption, data interception becomes pointless. The function of data compression
decreases the transmission time & probability of being interfered, while improving the reliability & transmission efficiency.
E30 series strictly stick to the design rules home and abroad of FCC, CE, CCC and meet the related RF certifications and export
standards.

SI4438 Wireless Module User Manual of E30 Series Modules
Copyright ©2012–2017, Chengdu Ebyte Electronic Technology Co., Ltd. 3/17
CONTENTS
1. Features.................................................................................................................................................................................... 4
2. Technical Parameters........................................................................................................................................................... 4
2.1 E30-TTL-100/ E30-T100S2............................................................................................................................................................................4
2.2 Parameters Notes............................................................................................................................................................................................5
3. Mechanical Characteristics................................................................................................................................................ 5
3.1 E30-TTL-100.................................................................................................................................................................................................... 5
3.1.1 Dimension.................................................................................................................................................................................................... 5
3.1.2 Pin Definition................................................................................................................................................................................................6
3.2 E30-T100S2...................................................................................................................................................................................................... 6
3.2.1 Dimension.................................................................................................................................................................................................... 6
3.2.2 Pin Definition................................................................................................................................................................................................7
4. Recommended Circuit Diagram.......................................................................................................................................7
5. Function Description............................................................................................................................................................8
5.1 Fixed Transmission..........................................................................................................................................................................................8
5.2 Broadcast Transmission................................................................................................................................................................................. 8
5.3 Broadcast Address.......................................................................................................................................................................................... 8
5.4 Monitor Address............................................................................................................................................................................................. 8
5.5 Reset.................................................................................................................................................................................................................. 9
5.6 AUX Description.............................................................................................................................................................................................. 9
5.6.1 Indication of UART Output.......................................................................................................................................................................... 9
5.6.2 Indication of Wireless Transmitting.............................................................................................................................................................9
5.6.3 Configuration Procedure of Module........................................................................................................................................................ 10
5.6.4 Notes for AUX............................................................................................................................................................................................ 10
6. Operating Mode.................................................................................................................................................................. 10
6.1 Mode Switch.................................................................................................................................................................................................. 11
6.2 Normal Mode (Mode 0)...............................................................................................................................................................................11
6.3 Wake-up Mode (Mode 1)........................................................................................................................................................................... 11
6.4 Power-saving Mode (Mode 2)................................................................................................................................................................... 12
6.5 Sleep Mode (Mode 3).................................................................................................................................................................................. 12
7. Instruction Format..............................................................................................................................................................12
7.1 Default Parameter.........................................................................................................................................................................................13
7.2 Reading Operating Parameters..................................................................................................................................................................13
7.3 Reading Version Number............................................................................................................................................................................13
7.4 Reset Instruction........................................................................................................................................................................................... 13
7.5 Parameter Setting Instruction.................................................................................................................................................................... 13
8. Parameter Setting...............................................................................................................................................................15
9. Production Guidance......................................................................................................................................................... 16
9.1 Reflow Soldering Temperature.................................................................................................................................................................. 16
9.2 Reflow Soldering Curve............................................................................................................................................................................... 16
10. FAQ........................................................................................................................................................................................17
10.1 Communication range is too short......................................................................................................................................................... 17
10.2 Module is easy to damage........................................................................................................................................................................17
11. Important Notes.............................................................................................................................................................. 17
12. About Us............................................................................................................................................................................. 17

SI4438 Wireless Module User Manual of E30 Series Modules
Copyright ©2012–2017, Chengdu Ebyte Electronic Technology Co., Ltd. 4/17
1. Features
Ultra-low power consumption: It supports WOR, which suits for battery power supply. In power-saving mode (Mode 2), the overall
power consumption can be regulated by setting receiving response delay and its maximum is 2000ms. The average current is about
30uA.
Fixed transmission: Module can communicate with other modules which work in different channels and addresses. It makes
networking and repeater easy. For example: module A transmits AA BB CC to module B (address: 0x00 01, channel: 0x80). The HEX
format is 00 01 80 AA BB CC (00 01 refers to the address of module B, and 80 refers to the channel of module B). Then module B
receives AA BB CC (only module B).
Broadcast transmission: When the module address is set as 0xFFFF, the module can communicate with other modules in the
same channel.
FEC: Forward Error Correction has high coding efficiency & good correction performance. In case of sudden interference, it can
correct the interfered data packets proactively, so that the reliability & transmission range are improved correspondingly. Without
FEC, those data packets can only be dropped.
Sleep mode: When the module works in sleep mode (Mode 3), it is available for configuration, but not for transmitting &
receiving. The typical current is 2.0uA in this mode.
Application: Compared with 2.4G, it is better in penetration and diffraction but less in speed rate. It is applicable in the open air
and places with a few obstacles.
2. Technical Parameters
Model
IC
Size
Net weight
Operating
temperature
Operating
humidity
Storage
temperature
E30-TTL-100
SI4438
21 * 36 mm
6.7±0.1g
-40 ~ 85℃
10% ~ 90%
-40 ~ 125°C
E30-T100S2
SI4438
17 * 30 mm
2.3±0.1g
-40 ~ 85℃
10% ~ 90%
-40 ~ 125°C
2.1 E30-TTL-100/ E30-T100S2
Parameter
Min
Typ
Max
Unit
Transmitting current
82
89
98
mA
Receiving current
15
16
17
mA
Turn-off current
3
4
5
μA
Transmitting power
19.3
20
20.6
dBm
Receiving sensitivity
-120
-121
-122
dBm
Voltage supply
2.3
3.3
5.2
V
Communication level
2.5
3.3
3.6
V

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2.2 Parameters Notes
When designing current supply circuit, 30% margin is recommended to be remained so as to ensure long-term stable operation of
the whole module.
The current at the instant of transmitting may be high, but the total energy consumed may be lower due to very short transmitting
time.
When using external antenna, the impedance matching degree at different frequency points between antenna and module may
affect the transmitting current at different levels.
The current consumed when the RF chip is only working at receiving mode is called as receiving current. The tested receiving
current may be higher for some RF chips with communication protocol or when the developers have loaded their own protocol to
the whole module.
The current at pure receiving mode is at mA level. To achieve µA level receiving current, the users need to manage it through
firmware development.
The receiving sensitivity is tested at the speed rate of 1kbps.
The turn-off current is always lower than the current consumed when the power supply source of the whole module is at no-load
status.
Each LRC component has ±0.1% error, and the error will accumulate since multiple LRC components are used in the whole RF
circuit, and the transmitting current will be different at different modules.
The power consumption can be lowered by lowering the transmitting power, but the efficiency of the internal PA will be decreased
by lowering transmitting power due to various reasons.
3. Mechanical Characteristics
3.1 E30-TTL-100
3.1.1 Dimension

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3.1.2 Pin Definition
Pin No.
Pin item
Pin direction
Pin application
1
M0
Input
（weak pull-up）
Work with M1 & decide the four operating modes.
(Floating is not allowed, can be ground)
2
M1
Input
（weak pull-up）
Work with M0 & decide the four operating modes.
(Floating is not allowed, can be ground)
3
RXD
Input
TTL UART inputs, connects to external (MCU, PC) TXD output pin. Can be configured as
open-drain or pull-up input.
4
TXD
Output
TTL UART outputs, connects to external RXD (MCU, PC) input pin. Can be configured as
open-drain or push-pull output
5
AUX
Output
To indicate module ’ s working status & wakes up the external MCU. During the
procedure of self-check initialization, the pin outputs low level. Can be configured as
open-drain output or push-pull output. (Floating is allowed)
6
VCC
Input
Power supply 2.3V~5.5V DC
7
GND
Input
Ground
8
Fixing hole
Fixing hole
9
Fixing hole
Fixing hole
10
Fixing hole
Fixing hole
3.2 E30-T100S2
3.2.1 Dimension

SI4438 Wireless Module User Manual of E30 Series Modules
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3.2.2 Pin Definition
Pin No.
Pin item
Pin direction
Pin application
1
M0
Input
（weak pull-up）
Work with M1 & decide the four operating modes.
(Floating is not allowed, can be ground)
2
M1
Input
（weak pull-up）
Work with M0 & decide the four operating modes.
(Floating is not allowed, can be ground)
3
RXD
Input
TTL UART inputs, connects to external (MCU, PC) TXD output pin. Can be
configured as open-drain or pull-up input.
4
TXD
Output
TTL UART outputs, connects to external RXD (MCU, PC) input pin. Can be
configured as open-drain or push-pull output
5
AUX
Output
To indicate module’s working status & wakes up the external MCU. During the
procedure of self-check initialization, the pin outputs low level. Can be configured
as open-drain output or push-pull output. (Floating is allowed)
6
VCC
Input
Power supply 2.3V~5.5V DC
7
GND
Input
Ground
8
ANT
Output
Antenna interface（ high frequency signal output）
9
GND
Output
Reference places of high frequency signal output
10
GND
Input
Ground
11
GND
Input
Ground
4. Recommended Circuit Diagram
No.
Description（STM8L MCU）
1
The UART module is TTL level. Please connect to MCU of TTL level.
2
For some MCU working at 5VDC, it may need to add 4-10K pull-up resistor for the TXD & AUX pin.

SI4438 Wireless Module User Manual of E30 Series Modules
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5. Function Description
5.1 Fixed Transmission
5.2 Broadcast Transmission
5.3 Broadcast Address
For example: Set the address of module A as 0xFFFF or 0 x0000, and channel as 0x04;
When module is the transmitter (transparent transmission), all modules under channel 0x04 will receive the data, the purpose of
broadcast is realized.
5.4 Monitor Address
For example: Set the address of module A as 0xFFFF or 0x0000, and channel as 0x04;
When module A is the receiver, it can receive the data sent from all modules under channel 0x04. The purpose of monitor is realized.

SI4438 Wireless Module User Manual of E30 Series Modules
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5.5 Reset
When the module is powered, AUX outputs low level immediately, conducts hardware self-check and sets the operating mode on the basis of the
user parameters. During the process, the AUX keeps low level. After the process completed, AUX outputs high level and starts to work as per the
operating mode combined by M1 and M0. Therefore, the user needs to wait the AUX rising edge as the starting point of module’s 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 are data that are not sent yet via
wireless way, 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 UART Output
To wake up external MCU:
5.6.2 Indication of Wireless Transmitting
Buffer (empty): the internal 512 bytes data in the buffer are written to the RFIC (Auto sub-packaging).
When AUX=1, the user can input data less than 512 bytes continuously without overflow. Buffer (not empty): when AUX=0, the
internal 512 bytes data in the buffer have not been written to the RFIC completely. If the user starts to transmit data at this
circumstance, it may cause overtime when the module is waiting for the user data, or transmitting wireless sub package.
Notes: When AUX = 1, it does not mean that all the UART data of the module have been transmitted already, perhaps the last packet
of data is still in transmission.

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5.6.3 Configuration Procedure of Module
Only happened when power-on resetting or exiting sleep mode.
5.6.4 Notes for AUX
For function 1 & function 2 mentioned above, the priority should be given to the one with low level output, which means if it meets
each of any low level output condition, AUX outputs low level, if none of the low level condition is met, AUX outputs high level.
When AUX outputs low level, it means the module is busy & cannot conduct operating mode checking. Within 1ms since AUX
outputs high level, the mode switch will be completed.
After switching to new operating mode, it will not work in the new mode immediately until AUX rising edge lasts for 2ms. If AUX
stays on the high level, the operating mode can be switched immediately.
When the user switches to other operating modes from mode 3 (sleep mode) or it’s still in reset process, the module will reset user
parameters. During it, AUX outputs low level.
6. Operating Mode
The table below shows the status of M1 & M0 and the corresponding modes: 
Mode（0-3）
M1
M0
Mode introduction
Remark
Mode 0
Normal
0
0
UART and wireless channel are open. Transparent transmission is on
The receiver must work in
mode 0 or mode 1
Mode 1
Wake-up
1
0
UART and wireless channel are open. The difference between normal
mode and wake-up mode is that it will add preamble code
automatically before data packet transmission so that it can awaken
the receiver works in mode 2
The receiver can work in
mode 0, mode 1 or mode 2
Mode 2
Power-saving
0
1
UART is disabled. Wireless module works at WOR mode (wake on
radio). It will open the UART and transmit data after receiving the
wireless data
1. The transmitter must
work in mode 1
2. Transmitting is not
allowed in this mode
Mode 3
Sleep
1
1
Parameter setting
More in working parameter

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6.1 Mode Switch
The user can decide the operating mode by the combination of M1 and M0. The two GPIOs of MCU can be used to switch mode.
After modifying M1 or M0, it will start to work in new mode 1ms later if the module is free. If there are any serial data that are yet to
finish wireless transmitting, it will start to work in new mode after the UART transmitting finished. After the module receives the
wireless data & transmits the data through serial port, it will start to work in new mode after the transmitting finished. Therefore,
the mode-switch is only valid when AUX outputs 1, otherwise it will delay.
For example, in mode 0 or mode 1, if the user inputs massive data consecutively and switches operating mode at the same time, the
mode-switch operation is invalid. New mode checking can only be started after all the user ’ s data process completed. It is
recommended to check AUX pin out status and wait 2ms after AUX outputs high level before switching the mode.
If the module switches from other modes to stand-by mode, it will work in stand-by mode only after all the remained data process
completed. The feature can be used to save power consumption. For example, when the transmitter works in mode 0, after the
external MCU transmits data “12345”, it can switch to sleep mode immediately without waiting the rising edge of the AUX pin, also
the user’s main MCU will go dormancy immediately. Then the module will transmit all the data through wireless transmission & go
dormancy 1ms later automatically, which reduces MCU working time & save power.
Likewise, this feature can be used in any mode-switch. The module will start to work in new mode within 1ms after completing
present mode task, which enables the user to omit the procedure of AUX inquiry and switch mode swiftly. For example, when
switching from transmitting mode to receiving mode, the user MCU can go dormancy before mode-switch, using external interrupt
function to get AUX change so that the mode-switch can be realized.
This operation is very flexible and efficient. It is totally designed on the basis of the user MCU’s convenience, at the same time the
work load and power consumption of the whole system has been reduced and the efficiency of whole system is largely improved.
6.2 Normal Mode (Mode 0)
When M1 = 0 & M0 = 0, module works in mode 0
Transmitting
The module can receive the user data via serial port, and transmit wireless data package of 58 bytes. When the data
inputted by user is up to 58 byte, the module will start wireless transmission. During which the user can input data
continuously for transmission.
When the required transmission bytes are less than 58 bytes, the module will wait 3-byte time and treat it as data
termination unless continuous data inputted by user. Then the module will transmit all the data through wireless
channel.
When the module receives the first data packet from user, the AUX outputs low level.
After all the data are transmitted into RF chip and transmission start , AUX outputs high level.
At this time, it means that the last wireless data package transmission is started, which enables the user to input another
512 bytes continuously. The data package transmitted from the module working in mode 0 can only be received by the
module working in mode 0 or 1.
Receiving
The wireless receiving function of the module is on, the data packet transmitted from the module working in mode 0 &
mode 1 can be received.
After the data packet is received, the AUX outputs low level, 5ms later the module starts to transmit wireless data
through serial port TXD pin.
After all the wireless data have been transmitted via serial port, the AUX outputs high level.
6.3 Wake-up Mode (Mode 1)
When M1 = 0 & M0 = 1, module works in mode 1
Transmitting
The condition of data packet transmission & AUX function is the same as mode 0. The only difference is that the
module will add preamble code before each data packet automatically. The preamble code length depends on the
wake-up time set in the user parameters. The purpose of the preamble code is waking up the receiving module works in
mode 2. Therefore, the data package transmitted from mode 1 can be received by mode 0, mode1 and mode 2.
Receiving
The same as that in mode 0.

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6.4 Power-saving Mode (Mode 2)
When M1 = 1 & M0 = 0, module works in mode 2
Transmitting
UART is closed, the module cannot receive any serial port data from outside MCU.
Hence the function of wireless transmission is not available for the module working in this mode.
Receiving
In mode 2, it is required the data transmitter works in mode 1.
The wireless module monitors the preamble code at regular time.
Once it gets the preamble code, it will remain as receiving status and waiting for the completion of receiving the entire
valid data package.
Then the AUX outputs low level, 5ms later the serial port is open to transmit received wireless data through TXD. Finally,
AUX outputs high level after process completed.
The wireless module stays in “power-saving – monitoring” working status (polling).
By setting different wake-up time, the module will have different receiving response delay (2s in maximum) and average
power consumption (30uA in minimum).
The user needs to achieve a balance between communication delay time & average power consumption.
6.5 Sleep Mode (Mode 3)
When M1=1, M0=1, module works in mode 3
Transmitting
N/A
Receiving
N/A
Parameter
setting
This mode can be used for parameter setting. It uses serial port 9600 & 8N1 to set module working parameters through
specific instruction format. (please refer to parameters setting for details)
Notes
When the mode changes from sleep mode to others, the module will reset its parameters, during which the AUX keeps low
level and then outputs high level after reset completed. User is recommended to check the AUX rising edge.
7. Instruction Format
In sleep mode（mode 3：M1=1, M0=1）, it supports instructions in the table below.
(Only support 9600 and 8N1 format when setting)
No.
Instruction format
Illustration
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.

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7.1 Default Parameter
Default parameter values：C0 00 00 18 50 44
Model
Frequency
Address
Channel
Air data rate
Baud rate
Parity
Transmitting power
E30-TTL-100
433MHz
0x0000
0x50
1kbps
9600
8N1
100mW
Default parameter values：C0 00 00 18 50 44
Model
Frequency
Address
Channel
Air data rate
Baud rate
Parity
Transmitting power
E30-T100S2
433MHz
0x0000
0x50
1kbps
9600
8N1
100mW
7.2 Reading Operating Parameters
Instruction format
Description
C1+C1+C1
In sleep mode（M0=1，M1=1），
User gives the module instruction (HEX format): C1 C1 C1,
Module returns the present configuration parameters.
For example, C0 00 00 1A 17 44.
7.3 Reading Version Number
Instruction format
Description
C3+C3+C3
In sleep mode（M0=1，M1=1）,
User gives the module instruction (HEX format): C3 C3 C3,
Module returns its present version number, for example C3 30 xx yy.
30 here means the module model (E30 series); xx is the version number and yy refers to the other module
features.
7.4 Reset Instruction
Instruction format
Description
C4+C4+C4
In sleep mode（M0=1，M1=1）,
User gives the module instruction (HEX format): C4 C4 C4, the module resets for one time. During the reset
process, the module will conduct self-check, AUX outputs low level. After reset completing, the AUX outputs
high level, then the module starts to work regularly which the working mode can be switched or be given
another instruction.
7.5 Parameter Setting Instruction
No.
Item
Description
Remark
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
UART mode can be different between
communication parties
0
0
8N1（default ）
0
1
8O1
1
0
8E1
1
1
8N1
5
4
3
TTL UART baud rate（bps）
UART baud rate can be different between

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communication parties
The UART baud rate has nothing to do
with wireless transmission parameters &
won’t affect the wireless transmit /
receive features.
0
0
0
1200bps
0
0
1
2400bps
0
1
0
4800bps
0
1
1
9600bps（default）
1
0
0
19200bps
1
0
1
38400bps
1
1
0
57600bps
1
1
1
115200bps
2
1
0
Air data rate（bps）
The lower the air data rate, the longer the
transmitting distance, better
anti-interference performance and longer
transmitting time
The air data rate must keep the same for
both communication parties.
0
0
0
1kbps
0
0
1
2kbps
0
1
0
5kbps（Default）
0
1
1
8kbps
1
0
0
10kbps
1
0
1
15kbps
1
1
0
20kbps
1
1
1
25kbps
4
CHAN
7
6
5
N/A
0
Communication channel
00H-FFH，for 425 ~ 450.5MHz
Communication frequency（425M+CHAN * 0.1M）
default 50H（433MHz）
5
OPTION
7
Fixed transmission（similar to MODBUS）
In 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.
0
Transparent transmission mode（default）
1
Fixed transmission mode
6
IO drive mode(the default 1)
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 and AUX push-pull outputs, RXD pull-up inputs
0
TXD、AUX open-collector outputs, RXD open-collector inputs
5
4
3
wireless wake-up time
The transmit & receive module work in
mode 0, whose delay time is invalid & can
be arbitrary value.
The transmitter works in mode 1 can
transmit the preamble code of the
corresponding time continuously.
When the receiver works in mode 2, the
time means the monitor interval time
(wireless wake-up). Only the data from
transmitter that works in mode 1 can be
received.
0
0
0
250ms（default）
0
0
1
500ms
0
1
0
750ms
0
1
1
1000ms
1
0
0
1250ms
1
0
1
1500ms
1
1
0
1750ms
1
1
1
2000ms
2
FEC switch
After turn off FEC, the actual data

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transmission rate increases while
anti-interference ability decreases. Also
the transmission distance is relatively
short.
Both communication parties must keep
on the same pages about turn-on or
turn-off FEC.
0
Turn off FEC
1
Turn on FEC（Default）
1
0
transmission power (approximation)
The external power must make sure the
ability of current output more than
250mA and ensure the power supply
ripple within 100mV.
Low power transmission is not
recommended due to its low power
supply efficiency.
0
0
20dBm（Default）
0
1
17dBm
1
0
14dBm
1
1
10dBm
For example: The meaning of No.3 "SPED" byte
The binary bit of the byte
7
6
5
4
3
2
1
0
The specific value
( configured by user)
0
0
0
1
1
0
1
0
Meaning
UART parity bit 8N1
UART baud rate is 9600
Air data rate is 2.4k
Corresponding hexadecimal
1
A
8. Parameter Setting
When the module is in mode 3 (M1=1 M0=1), the parameter can be set by instruction or software in PC.
Please visit www.cdebyte.com to download the software.

SI4438 Wireless Module User Manual of E30 Series Modules
Copyright ©2012–2017, Chengdu Ebyte Electronic Technology Co., Ltd. 16 /17
9. Production Guidance
9.1 Reflow Soldering Temperature
Profile Feature
Sn-Pb Assembly
Pb-Free Assembly
Solder Paste
Sn63/Pb37
Sn96.5/Ag3/Cu0.5
Preheat Temperature min （Tsmin）
100℃
150℃
Preheat temperature max (Tsmax)
150℃
200℃
Preheat Time (Tsmin to Tsmax)(ts)
60-120 sec
60-120 sec
Average ramp-up rate(Tsmax to Tp)
3℃/second max
3℃/second max
Liquidous Temperature (TL)
183℃
217℃
Time（tL）Maintained Above（TL）
60-90 sec
30-90 sec
Peak temperature（Tp）
220-235℃
230-250℃
Aveage ramp-down rate（Tp to Tsmax）
6℃/second max
6℃/second max
Time 25℃ to peak temperature
6 minutes max
8 minutes max
9.2 Reflow Soldering Curve

SI4438 Wireless Module User Manual of E30 Series Modules
Copyright ©2012–2017, Chengdu Ebyte Electronic Technology Co., Ltd. 17 /17
10. FAQ
10.1 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.
Seawater 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).
When the power supply at room temperature is lower than the recommended low voltage, the lower the voltage is, the lower the
transmitting power is.
Due to antenna quality or poor matching between antenna and module.
10.2 Module is easy to damage
Please check the power supply and ensure it is within the recommended range. Voltage higher than the peak will lead to a
permanent damage to the module.
Please check the stability of power supply and ensure the voltage not to fluctuate too much.
Please make sure anti-static measures are taken when installing and using, high frequency devices have electrostatic susceptibility.
Please ensure the humidity is within limited range for some parts are sensitive to humidity.
Please avoid using modules under too high or too low temperature.
11. Important Notes
All rights to interpret and modify this manual belong to Ebyte.
This manual will be updated based on the upgrade of firmware and hardware, please refer to the latest version.
Please refer to our website for new product information.
12. About Us
Technical support: [email protected]
Documents and RF Setting download link: www.cdebyte.com/en/
Tel：[phone]
Fax：[phone]
Web：www.cdebyte.com/en/
Address：Innovation Center D347, 4# XI-XIN Road, Chengdu, Sichuan, China