原标题：ADI ADRF6807 2.8-4.2 GHz大动态范围IQ解调方案

　　ADI公司的ADRF6807是工作在2.8-4.2GHz的集成了PLL和VCO的大动态范围IQ解调器,LO频率范围700MHz到1050MHz,IP3可达26.7dBm,噪音(DSB)为13.1dB,电压转换增益1.0dB/4.3dB.相位正交解调精度优于0.5度,幅度正交解调精度优于0.1dB,基带解调170MHz/135MHz,3dB带宽,PLL编程采用SPI串口,主要用在QAM/QPSK RF/IF解调器,蜂窝W-CDMA/CDMA/CDMA2000,微波点对点(多点)无线电,宽带无线和WiMAX.本文介绍了ADRF6807主要特性,方框图, 基本的连接电路, 评估板电路图和材料清单(BOM), 评估板元件布局图以及评估板通用特性,噪音特性别和相位噪音特性测试图.

　　The ADRF6807 is a high dynamic range IQ demodulator with integrated phase-locked loop (PLL) and voltage controlled oscillator (VCO). The fractional-N PLL/synthesizer generates a frequency in the range of 2.8 GHz to 4.2 GHz. A programmable quadrature divider (divide ratio = 4) divides the output frequency of the VCO down to the required local oscillator (LO) frequency to drive the mixers in quadrature. Additionally, an output divider (divide ratio = 4 to 8) generates a divided-down VCO signal for external use. The PLL reference input is supported from 9 MHz to 160 MHz. The phase detector output controls a charge pump whose output is integrated in an off-chip loop filter. The loop filter output is then applied to an integrated VCO. The IQ demodulator mixes the differential RF input with the complex LO derived from the quadrature divider. The differential I and Q output paths have excellent quadrature accuracy and can handle baseband signaling or complex IF up to 120 MHz. A reduced power mode of operation is also provided by programming the serial interface registers to reduce current consumption, with slightly degraded input linearity and output current drive. The ADRF6807 is fabricated using an advanced silicon-germanium BiCMOS process. It is available in a 40-lead, exposed paddle, RoHS-compliant, 6 mm × 6 mm LFCSP package. Performance is specified over the −40℃ to +85℃ temperature range.

　　ADRF6807主要特性:

　　IQ demodulator with integrated fractional-N PLL

　　LO frequency range: 700 MHz to 1050 MHz

　　For the following specifications (LPEN = 0)/(LPEN = 1):

　　Input P1dB: 12.8 dBm/11.7 dBm Input

　　IP3: 26.7 dBm/24.0 dBm

　　Noise figure (DSB): 13.1 dB/12.4 dB

　　Voltage conversion gain: 1.0 dB/4.3 dB

　　Quadrature demodulation accuracy

　　Phase accuracy: <0.5°

　　Amplitude accuracy: <0.1 dB

　　Baseband demodulation: 170 MHz/135 MHz, 3 dB bandwidth

　　SPI serial interface for PLL programming

　　40-lead, 6 mm × 6 mm LFCSP

　　ADRF6807应用:

　　QAM/QPSK RF/IF demodulators

　　Cellular W-CDMA/CDMA/CDMA2000

　　Microwave point-to-(multi)point radios

　　Broadband wireless and WiMAX

　　图1.ADRF6807方框图

　　图2.ADRF6807基本的连接图

　　图3.ADRF6807评估板电路图

　　ADRF6807评估板材料清单(BOM):

　　图6.ADRF6807评估板通用特性测试图

　　图7.ADRF6807评估板噪音特性测试图

　　图8.ADRF6807评估板相位噪音特性测试图