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RFM22B-868-S1 参数 Datasheet PDF下载

RFM22B-868-S1图片预览
型号: RFM22B-868-S1
PDF下载: 下载PDF文件 查看货源
内容描述: ISM收发器模块 [ISM TRANSCEIVER MODULE]
分类和应用: ISM频段
文件页数/大小: 70 页 / 2627 K
品牌: HOPERF [ HOPERF ]
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RFM22B/23B  
the output from the -modulator. The tuning resolution is sufficient to tune to the commanded frequency with a  
maximum accuracy of 312.5 Hz anywhere in the range between 240–960 MHz.  
5.6.1. VCO  
The output of the VCO is automatically divided down to the correct output frequency depending on the hbsel and  
fb[4:0] fields in "Register 75h. Frequency Band Select." In receive mode, the LO frequency is automatically shifted  
downwards by the IF frequency of 937.5 kHz, allowing transmit and receive operation on the same frequency. The  
VCO integrates the resonator inductor and tuning varactor, so no external VCO components are required.  
The VCO uses a capacitance bank to cover the wide frequency range specified. The capacitance bank will  
automatically be calibrated every time the synthesizer is enabled. In certain fast hopping applications this might not  
be desirable so the VCO calibration may be skipped by setting the appropriate register.  
5.7. Power Amplifier  
The RFM22B contains an internal integrated power amplifier(PA) capable of transmitting at output levels between –1  
and +20 dBm. The RFM23B contains a PA which is capable of transmitting output levels between –8 to  
+13 dBm. The PA design is single-ended and is implemented as a two stage class CE amplifier with a high  
efficiency when transmitting at maximum power. The PA efficiency can only be optimized at one power level.  
Changing the output power by adjusting txpow[2:0] will scale both the output power and current but the efficiency  
will not remain constant. The PA output is ramped up and down to prevent unwanted spectral splatter.  
For the RFM23B, The direct tie is used, The lna_sw bit in “Register 6Dh. TX Power” must be set.  
.
5.7.1. Output Power Selection  
The output power is configurable in 3 dB steps with the txpow[2:0] field in "Register 6Dh. TX Power." Extra output  
power can allow the use of a cheaper smaller antenna, greatly reducing the overall BOM cost. The higher power  
setting of the chip achieves maximum possible range, but of course comes at the cost of higher TX current  
consumption. However, depending on the duty cycle of the system, the effect on battery life may be insignificant.  
lp in evaluating  
Contact HOPERF Support for he  
this tradeoff.  
D7  
D6  
D5  
D4  
D3  
D2  
D1  
D0  
POR  
Def.  
Add R/W Function/D  
escription  
6D R/W  
TX Power  
papeakval papeaken papeaklv[1] papeaklv[0] lna_sw txpow[2] txpow[1] txpow[0] 18h  
txpow[2:0]  
000  
RFM22B Output Power  
+1 dBm  
001  
+2 dBm  
010  
+5 dBm  
011  
+8 dBm  
100  
+11 dBm  
101  
+14 dBm  
110  
+17 dBm  
111  
+20 dBm  
txpow[2:0]  
000  
RFM23B Output Power  
–8 dBm  
001  
–5 dBm  
010  
011  
100  
101  
110  
111  
–2 dBm  
+1 dBm  
+4 dBm  
+7 dBm  
+10 dBm  
+13 dBm  
Tel: +86-755-82973805 Fax: +86-755-82973550 E-mail: sales@hoperf.com http://www.hoperf.com  
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