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E78-400M22S User Manual
ASR6501 433/470MHz 22dBm LoRa Wireless Module
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Chengdu Ebyte Electronic Technology Co.,Ltd E78-400M22S user manual
Content
1.Overview
2. Specification and parameter
3. Size and pin definition
4.Development
6.Basic operation
7.FAQ
8. Production guidance
9. Antenna recommendation
10. Package for batch order
Revision history
About us
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1.1 Introduction
1.2 Features
1.3 Application
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2.1 Limit parameter
2.2 Operating parameter
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6.1 Hardware design
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7.1 Communication range is too short
7.2 Module is easy to damage
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7.3 BER(Bit Error Rate) is high
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8.1 Reflow soldering temperature
8.2 Reflow soldering curve
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Chengdu Ebyte Electronic Technology Co.,Ltd E78-400M22S user manual
1.1 Introduction
E78-400M22S is a SoC LoRa RF module designed by Ebyte, working at
410 ~ 493MHz (default is 433MHz) with max transmitting power of 22dBm.
With ASR company's ASR6501 chip, which is an ultra-low power LoRa
integrated single chip SoC, Semtech advanced low power LoRa Transceiver
SX1262, and integrated a Cypress 32-bit cor-m0 + low power MCU, Flash
capacity 128kB, SRAM capacity 16kB, ultra-small size, ultra-low power, the
1.Overview
module supports LoRaWAN, LinkWAN protocol standards, suitable for a variety of Internet of things application
scenarios. It is currently the best choice for LPWAN application chips.
E78-400M22S is a hardware platform and cannot be used directly. Users need to conduct secondary development
(Ebyte can customize standard LoRaWan and Alibaba linkWan nodes for you).
1.2 Features
Ultra-small size, only 14x20mm;
Under ideal conditions, the communication distance can reach 7km;
Integrated Cypress 32-bit cortex-m0 + low-power MCU;
Maximum transmission power 160mW, multi-stage adjustable software;
Support global license-free ISM 433/470mhz frequency band;
Support ultra-low power consumption, very low power consumption;
In LoRa mode, data transmission rate of 0.018k ~ 62.5kbps is supported.
Supports data transmission rate up to 300kbps in FSK mode;
New SF5 spread spectrum factor to support dense networks;
Industry-standard design, support - 40 ~ + 85 ℃ under long time use;
Dual antenna is optional (IPEX/ stamp hole), which is convenient for users' secondary development and convenient
for integration.
1.3 Application
Smart home and industrial sensors;
Security system, positioning system;
Building automation solutions;
Wireless remote control, UAV;
Wireless game remote control;
Healthcare products;
Wireless voice, wireless headphones;
Advanced meter reading architecture (AMI);
Automotive applications.
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Chengdu Ebyte Electronic Technology Co.,Ltd E78-400M22S user manual
Voltage over 5.2V will cause permanent
damage to module
Chances of burn is slim when modules
are used in short distance
≥3.3 V ensures output power
For 5V TTL, it may be at risk of
burning down
Transmitting current
[mA]
Instant power consumption
Receiving sensitivity(dBm)
Air data rate is 0.018kbps
Test condition:clear and open area, antenna gain: 5dBi
,
antenna height: 2.5m,air data rate: 1kbps
Active temperature complementary crystal vibration
2. Specification and parameter
2.1 Limit parameter
2.2 Operating parameter
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Chengdu Ebyte Electronic Technology Co.,Ltd E78-400M22S user manual
Ground wire, connected to the power reference ground
Power supply, range 2.5-3.7v (external ceramic filter capacitor is
recommended)
Ground wire, connected to the power reference ground
Multipurpose digital IO cannot be used as external GPIO
SPI busy indicator that cannot be used as an external GPIO
3. Size and pin definition
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Chengdu Ebyte Electronic Technology Co.,Ltd E78-400M22S user manual
Ground wire, connected to the power reference ground
Antenna interface, stamp hole (50 ohm characteristic impedance)
Ground wire, connected to the power reference ground
Ground wire, connected to the power reference ground
Ground wire, connected to the power reference ground
Ground wire, connected to the power reference ground
Ground wire, connected to the power reference ground
SPI MISO test point, internally connected, cannot be used as external SPI
SPI NSS test point, internally connected, cannot be used as an external SPI
SPI MOSI test point, internally connected, cannot be used as an external SPI
SPI SCK test point, internally connected, cannot be used as external SPI
Module is SoC module, with GPIO port, program download using ASR official test board;
Connect XRES, SWD_CLK, SWD_DATA, GND, 3V3 of the test board on the official website with
XRES, SCLK, SDAT, GND and 3V3 of the downloader respectively, and ensure that both green lights
are on before downloading. If there is any exception, please press this button to ensure that both green
lights are on. (for details, please refer to the official ASR6501 burning instructions)
4.Development
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Chengdu Ebyte Electronic Technology Co.,Ltd E78-400M22S user manual
It is suggested that we can first use our testing base e78-tbl-01 specially made for E78 module, which
is convenient for users to use, and users can decide according to their own needs.
6.Basic operation
6.1 Hardware design
It is recommended to use dc stabilized voltage power supply to supply power to this module. The ripple coefficient
of the power supply should be as small as possible and the module should be grounded reliably.
Please pay attention to the correct connection of the positive and negative poles of the power supply.
Please check the power supply to ensure that it is between the recommended power supply voltage. If the maximum
value is exceeded, the module will be permanently damaged.
Please check the stability of the power supply, the voltage cannot fluctuate greatly and frequently;
When designing power supply circuit for modules, it is often recommended to keep more than 30% allowance,
which is conducive to long-term stable work of the whole machine.
Module should be as far as possible away from the power supply, transformers, high frequency wiring and other
electromagnetic interference large part;
High frequency digital wiring, high frequency analog wiring and power supply wiring must avoid the Bottom of the
module. If it is really necessary to pass the Bottom of the module, assume that the module is welded to the Top
Layer and copper is laid on the Top Layer in the contact part of the module (all copper is laid and well grounded). It
must be close to the digital part of the module and wired on the Bottom Layer.
Assuming that the module is welded or placed in Top Layer, it is also wrong to randomly line Bottom Layer or other
layers, which will affect the spurious and receiving sensitivity of the module to varying degrees.
It is assumed that there are devices with large electromagnetic interference around the module, which will greatly
affect the performance of the module. According to the intensity of interference, it is suggested to stay away from
the module appropriately. If possible, appropriate isolation and shielding can be done.
It is assumed that the wiring around the module with large electromagnetic interference (high frequency digital,
high frequency analog, power supply wiring) will also greatly affect the performance of the module. According to
the intensity of interference, it is suggested to stay away from the module. If possible, appropriate isolation and
shielding can be done.
If 5V level is used for communication line, 1k-5.1k resistance must be connected in series (not recommended, there
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Chengdu Ebyte Electronic Technology Co.,Ltd E78-400M22S user manual
is still risk of damage);
As far as possible away from some physical layer also 2.4GHz TTL protocol, such as: USB3.0;
Antenna installation structure has a great impact on the performance of the module, it must be ensured that the
antenna is exposed and preferably vertical;
When the module is installed inside the housing, a high-quality antenna extension cord can be used to extend the
antenna to the outside of the housing.
The antenna must not be installed in the inner part of the metal shell, which will greatly weaken the transmission
distance.
7.FAQ
7.1 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.
7.2 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.
Please avoid using modules under too high or too low temperature.
7.3 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;
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Preheat Temperature min (Tsmin)
Preheat temperature max (Tsmax)
Preheat Time (Tsmin to Tsmax)(ts)
Average ramp-up rate(Tsmax to Tp)
Liquidous Temperature (TL)
Time(tL)Maintained Above(TL)
Time below liquid phase
line
Average ramp-down rate(Tp to Tsmax)
Time 25℃ to peak temperature
Time to peak temperature
for 25℃
8. Production guidance
8.1 Reflow soldering temperature
8.2 Reflow soldering curve
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Soft inside,FPC soft antenna
Flexible &omnidirectional
Flexible &omnidirectional
Flexible &omnidirectional
Flexible &omnidirectional
Sucker antenna, High gain
Sucker antenna, High gain
Car Sucker antenna, High
gain
Short straight &omnidirectional
Short straight &omnidirectional
Sucker antenna, High gain
Short straight &omnidirectional
9. Antenna recommendation
The antenna is an important role in the communication process. A good antenna can largely improve the
communication system. Therefore, we recommend some antennas for wireless modules with excellent performance and
reasonable price.
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Chengdu Ebyte Electronic Technology Co.,Ltd E78-400M22S user manual
10. Package for batch order
Revision history
About us
Website: www.ebyte.com Sales: info@cdebyte.com Support: support@cdebyte.com
Tel: +86-28-61399028 Ext. 812 Fax: +86-28-64146160
Address: Innovation Center B333~D347, 4# XI-XIN road,High-tech district (west), Chengdu, Sichuan,
China
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