The module uses Silicon Labs' Si4432 as a wireless transceiver chip, which is a complete, compact, low-power wireless transceiver module. SI4432 is one of the Silicon Labs EZRadioPRO series ISM band wireless chips launched by Silicon Company in 2009. It can work in the 240-960 MHZ frequency band, and the maximum output power can reach +20DBm, which satisfies the development of RF signal amplification to a certain extent. difficult question. Under the condition of the maximum power setting, the open communication distance can reach several kilometers. The module integrates all RF-related functions and devices. Users can use this module to easily develop stable and reliable wireless-related products without any knowledge of radio.
The communication distance of SI4432 itself is not more than 1000 meters under the condition of 20dBm. In some special applications, a longer distance is required. The RFCSI4432A module is based on the peripheral circuit of the original SI4432 module. The power is as high as 33dBm (about 2W), which directly improves the communication distance of the module (above 3000 meters), meets various application problems, and makes wireless applications, distance is no longer a problem.
Basic Features
Frequency range: 240—960MHZ Receiving sensitivity: -115 dBm (baud rate 9.6Kbps)
Communication baud rate: 1—128kbps
Maximum transmit power: 33dBm
Current in shutdown mode: 10nA
The current in sleep mode is: 300nA
FSK frequency offset programmable (15~240KHz)
FSK frequency offset programmable (15~240KHz)
Programmable receiving bandwidth (67~400KHz)
Power amplifier with automatic slope control and spectral shaping
33dBm, strong transmission energy, open communication distance of more than 3000 meters
SPI-compatible control interface, low-power task cycle mode, built-in wake-up timer
On-chip low battery detection, temperature sensor, voltage regulator
Typical main application
Vehicle monitoring, remote control, telemetry, hydrometeorological monitoring
Wireless tags, identification, contactless RF smart cards
Small wireless network, wireless meter reading, access control system, cell paging
Industrial data acquisition system, wireless 232 data communication, wireless 485/422 data communication
Small wireless data terminal, security fire protection system, remote control system, biological signal acquisition
Remark
The voltage range of the VCC5 pin is between 4V and 5V. The recommended voltage is 4.5V, which cannot be outside this voltage range. If ordinary dry batteries are used, the recommended power supply voltage is 5.5V; if it is powered by lithium batteries, the power supply voltage is 4.5V. Note: The characteristics of NiMH batteries and dry batteries are different. If the power supply of NiMH batteries is greater than 5V, the wireless module will be permanently burned out! The main reason is that the internal resistance of ordinary dry batteries is large, and there is a current of 150mA at the moment when the module is working in the transmitting state to emit electromagnetic waves (actually, because the tantalum capacitors are placed in our internal circuit to act as a reservoir, the instantaneous current becomes smaller), while dry batteries The internal resistance divider voltage is as high as 1V to 2V, so in order to maintain normal operation, the dry battery needs a power supply voltage of 5.5V, so it is not recommended to use dry batteries for power supply. Lithium battery power is recommended. Generally speaking, the higher the power, the higher the power requirements. If it is a 200W high-power transmitter, the requirements for the power supply are more stringent, and there are even strict requirements for the power switch sequence. If the power itself is small, the current is relatively small. (<100mA) this problem is not obvious. Note that when laying the power line, pay attention to adding tantalum capacitors, generally >100uA, it is best to add 470uF tantalum capacitors to filter and store charges, especially after using a booster circuit, the output current of some booster circuits is less than 400mA, it can be used in front of the battery at this time, but it is also necessary to prevent the transmission frequency from being too high, and the battery's electricity cannot make ends meet, which can be avoided by an appropriate delay (20ms). The phenomenon of battery overdraft can be avoided.
2. The voltage range of the VCC3.3 pin is between 1.9-3.6V. It cannot be outside this range. If it exceeds 3.6V, the module will be burned. The recommended voltage is about 3.3V;
3. The single chip microcomputer without integrated SPI function in the hardware can also control the module, just use the ordinary single chip IO port to simulate the SPI timing for read and write operations;
4. The module interface adopts standard 2.54mm DIP pins, all GND It needs to be connected with the logic ground of the system circuit;
5. When connecting with the P0 port of the 51 series microcontroller, a 10K pull-up resistor needs to be added, and it is not necessary to connect with other ports. Other series of 5V microcontrollers,如AVR、PIC，请参考该系列单片机 IO 口输出电流大小，如果超过 10mA，需要串联2-5K电阻分压，否则容易烧毁模块! 如果是 3.3V 的MCU，可以直接和IO口连接。
模块电气参数
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参数
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数值
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单位
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芯片工作电压
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1.8-3.6
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V
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运放工作电压
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4.5-5
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V
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最大发射功率
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33
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dBm
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最大数据传输率
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128
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kbps
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温度范围
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-40 to +85
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|
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典型灵敏度
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-107（40kbps条件）
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dBm
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