RF2948B RF Micro Devices, RF2948B Datasheet
RF2948B
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RF2948B Summary of contents
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... IEEE 802.11b WLANs • Wireless Residential Gateways • Secure Communication Links Product Description The RF2948B is a monolithic integrated circuit specifi- cally designed for direct-sequence spread-spectrum sys- tems operating in the 2.4GHz ISM band. The part includes: a direct conversion from IF receiver with vari- able gain control ...
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... RF2948B Absolute Maximum Ratings Parameter Supply Voltage Control Voltages Input RF Level LO Input Levels Operating Ambient Temperature Storage Temperature o MSL JEDEC level 3 at 240 C Parameter Min. Overall Receiver RX Frequency Range Cascaded Voltage Gain Cascaded Noise Figure Cascaded Input IP3 Cascaded Input IP3 ...
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... RF2948B Unit Condition dB Any setting MHz 5th order Bessel LPF, Set by BW CTRL 35MHz, increasing as bandwidth decreases 2MHz. dB kΩ Single-ended mV Linear, Single-ended. p-p mV Single-ended. p-p V For correct operation. ...
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... RF2948B Parameter Min. Transmit Power Amp Linear Output Power Gain Output P1dB Output Impedance Input Impedance Power Down Control Logical Controls “ON” Logical Controls “OFF” -0.3 Control Input Impedance RX V Response TIme Response TIme TX EN Response TIme Response TIme ...
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... Power supply for transmitter bias generator OUT This is the output transistor of the power amp stage open col- lector output. The output match is formed by an inductor to V supplies DC and a series cap. Rev A6 040930 RF2948B Interface Schematic VCC 10 kΩ Pins ESD See pin 1 ...
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... RF2948B Pin Function Description Input to the power amplifier stage. This is a 50Ω input. Requires DC- blocking/tuning cap. 14 VCC5 Supply for the RF LO buffer, RF upconverter and amplifier Single-ended LO input for the transmit upconverter. External matching to 50Ω and a DC-block are required. ...
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... PCB groundplane is essential for good performance. Use Base an array of vias immediately underneath the device. ESD This diode structure is used to provide electrostatic discharge protec- tion to 3kV using the Human body model. The following pins are pro- tected: 1- 10, 19-32. Rev A6 040930 RF2948B Interface Schematic V CC 11-245 ...
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... RF2948B State Decode Table Sleep Mode Receive Mode Transmit Mode NOTES BB_EN Enables: RXIF_EN Enables: TXRF_EN Enables: 11-246 Input Pins Internally Decoded Signals TX_LPF’s and buffers Quad Demodulator mixers Baseband Amps and gm-C LPF’s ...
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... Logic RX IF BIAS 3 REF VCC1 VCC9 7 TX VGC 8 Phase ÷2 Splitter Rev A6 040930 Control DC Feedback Σ RF2948B gm-C LPF DC Feedback gm-C 24 LPF TX 23 Bias gm-C 22 LPF 21 gm-C 20 LPF OUT ...
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... LO INPUT BUFFERS RF LO Buffer The RF LO input has a limiting amplifier before the mixer on both the RF2494 (RX) and RF2948B (TX). This limiting amplifier design and layout is identical on both ICs, which will make the input impedance the same as well. Having this amplifier between the VCO ...
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... SAW filters and image filters with different insertion loss values. This gain could also be adjusted real time, if desired. Rev A6 040930 RF2948B TX Upconverter The upconverter is a double-balanced differ- ential mixer with a differential to single-ended con- verter on the output to supply 0dBm peak linear power to the image filter ...
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... RF2494 SSOP-16 EPP SAW max +45° -45° 10 dBm PA Driver TX VGC IL = 1-3 dB 2.4 to 2.483 GHz RF2948B RX VGC OUT Q IF Amp OUT I Base Band Amp. Active Selectable LPF ( MHz to 40 MHz) C Filter I INPUT Σ Filter Selectable LPF Q INPUT Rev A6 040930 ...
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... VREF1 BUF R7 GND 0 Ω OUT R8* GND 0 Ω *Configured for RX Demod and TX Cascaded Evaluation 50 Ω µstrip Populate Unpopulate Changes R11 R62 N R10 R9, R61 R56 to 0 RF2948B 24 C52 VCC C47 C48 C91 C90 5 pF L16 R48 R39 3 ...
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... RF2948B Board Thickness 0.031”, Board Material FR-4, Multi-Layer 11-252 Evaluation Board Layout Board Size 2.2” x 2.1” Rev A6 040930 ...
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... TX 3dB BW Point versus R =3.15V, V =1.6V 50.0 45.0 40.0 35.0 30.0 25.0 20.0 15.0 10.0 5.0 0.0 100.0 1000.0 1.0 RF2948B RX Gain versus IF LO Amplitude and Temp V =1.6V IN=375MHz, I and Q OUT~650mV ; IF LO=748MHz) GC P-P Gain, 25°C Gain, 85°C Gain, -40°C -25.0 -20.0 -15.0 -10.0 -5.0 LO Ampl. (dBm) RX OP1dB versus VGC and Temp ( MHz 748 MHz at -10 dBm) 1 ...
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... RF2948B Modulator Amplitude Error and Image Suppression versus IF LO Amplitude and Temp (V =3V; IF LO=748MHz; IQ IN=1MHz @ 100mV CC 1.0 Ampl.Err, 25°C Ampl. Err, 85°C 0.9 Ampl. Err, -40°C Image Supp, 25°C Image Supp, 85°C 0.8 Image Supp, -40°C 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 -30.0 -26.0 -22.0 -18.0 -14.0 -10.0 LO Amplitude (dBm) Upconverter Voltage Gain versus IN=374MHz @ -35dBm, RF LO=2068MHz @ -5dBm) 14 ...
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... PA Gain versus V CC (PA IN=2442MHz @ -30dBm) 10.1 10.0 9.9 9.8 9.7 9.6 9.5 9.4 9.3 9.2 9.1 9.0 8.9 8.8 8.7 8.6 8.5 8.4 8.3 8.2 8.1 8.0 2.7 3 Rev A6 040930 and Temp 15.0 14.5 14.0 13.5 13.0 12.5 12.0 11.5 11.0 10.5 Gain, 25°C 10.0 Gain, 85°C 9.5 Gain, -40°C 9.0 3.3 2.7 ) RF2948B PA Output P1dB versus V and Temp CC (PA IN=2442MHz) OP1dB, 25°C OP1dB, 85°C OP1dB, -40°C 3 3.3 11-255 ...
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... RF2948B 11-256 Rev A6 040930 ...