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RF Design Lab
RF Design Lab
RF Design Lab
I have some problems about ADRF 6655 and ADF4360-7.
Q1. About ADRF6655 evaluation board
Q1.1 : about conversion gain
Q1.2 : about IF frequency
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RF Design Lab
UP-Converter(ADRF6655)
Q1.1
I measured ADRF6655 output signal through spectrum analyzer
But measured conversion gain is about - 6 dB in the spectrum analyzer.
(voltage conversion gain : 6 dB in datasheet)
Is this voltage conversion gain of 6 dB ? Is that correct ??
 Our measurement set-up and software set-up are shown in Page 4~7
 Could you check these pages ? I don’t know what is problem. Why is the measured
conversion gain of -6 dB ? (voltage conversion gain : 6 dB in datasheet)
Q1.2 When I measured the ADRF6655 as up-converter using internal LO frequency.
Some frequency don’t normally operate.
RF input frequency: 470~ 698 MHz our target IF frequency is 1220 MHz
But another IF frequencies occurred at some RF input frequencies.
RF: 490 MHz, LO: 1710 MHz  measured IF : 1380 MHz ( target IF: 1220 MHz)
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RF Design Lab
UP-Converter(ADRF6655)
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DC power
supply
VCC: 5 V
IP3SET: 3.2 V
RF frequency: 470~698 MHz
Input power level: -20 dBm
Signal
generator
REFIN: 20 MHz, 1V
ADRF6655
- This is our measurement set-up for ADRF6655
- Bias voltages
1. REFIN: 20 MHz, 1 V
2. Vcc: 5 V
3. IP3SET: 3.2 V
-
We measured ADRF6655 with bias voltages in measurement set-up
Spectrum
analyzer
Measured output power level:
About -26 dBm
RF Design Lab
UP-Converter(ADRF6655)
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Vcc: 5 V
IP3SET: 3.2 V
Signal generator
:20 MHz
Spectrum
analyzer
RF Design Lab
UP-Converter(ADRF6655)
Is this setting all right?
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RF Design Lab
UP-Converter(ADRF6655)
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REFIN: 20 MHz
LO Frequency
:1690 ~ 1918MHz
RF frequency
:470 ~ 698MHz
IF:1220 MHz
Is this setting all right?