原标题：ADI ADF4355微波宽带(54-6800 MHz)频率合成器解决方案

　　ADI公司的ADF4355是微波宽带(54-6800MHz)可实现小数N分频或整数N分频锁相环(PLL)的频率合成器,高分辨率38位模数,低相位噪声电压控制振荡器(VCO),可编程1/2/4/8/16/32/64分频输出,模拟和数字电源为3.3 V,主要用在无线基础设施(W-CDMA,TD-SCDMA,WiMAX,GSM, PCS,DCS,DECT),点到点/点到多点微波链路,卫星/VSAT ,测试设备/仪器仪表和时钟产生.本文介绍了ADF4355主要特性,框图和几种应用电路,以及评估板EV-ADF4355SD1Z主要特性,电路图,材料清单和PCB设计图.

　　The ADF4355 allows implementation of fractional-N or integer-N phase-locked loop (PLL) frequency synthesizers when used with an external loop filter and an external reference frequency. A series of frequency dividers permits operation from 54 MHz to 6800 MHz.

　　The ADF4355 has an integrated VCO with a fundamental output frequency ranging from 3400 MHz to 6800 MHz. In addition, the VCO frequency is connected to divide by 1, 2, 4, 8, 16, 32, or 64 circuits that allow the user to generate RF output frequencies as low as 54 MHz. For applications that require isolation, the RF output stage can be muted. The mute function is both pin and software controllable.

　　Control of all on-chip registers is through a simple 3-wire interface. The ADF4355 operates with analog and digital power supplies ranging from 3.15 V to 3.45 V, with charge pump and VCO supplies from 4.75 V to 5.25 V. The ADF4355 also contains hardware and software power-down modes.

　　ADF4355主要特性:

　　RF output frequency range: 54 MHz to 6800 MHz

　　Fractional-N synthesizer and integer-N synthesizer

　　High resolution 38-bit modulus

　　Low phase noise, voltage controlled oscillator (VCO)

　　Programmable divide by 1, 2, 4, 8, 16, 32, or 64 output

　　Analog and digital power supplies: 3.3 V

　　Charge pump and VCO power supplies: 5.0 V typical

　　Logic compatibility: 1.8 V

　　Programmable dual modulus prescaler of 4/5 or 8/9

　　Programmable output power level

　　RF output mute function

　　3-wire serial interface

　　Analog and digital lock detect

　　ADF4355应用:

　　Wireless infrastructure (W-CDMA, TD-SCDMA, WiMAX, GSM, PCS, DCS, DECT)

　　Point to point/point to multipoint microwave links

　　Satellites/VSATs

　　Test equipment/instrumentation

　　Clock generation

　　图1.ADF4355功能框图

　　图2. ADF4355直接转换调制器电路图

　　图3. ADF4355功电源电路图

　　评估板EV-ADF4355SD1Z

　　The EV-ADF4355SD1Z evaluates the performance of the ADF4355 frequency synthesizer with integrated VCO for phase-locked loops (PLLs). A photograph of the evaluation board is shown in Figure 1. The evaluation board contains the ADF4355 frequency synthesizer with integrated VCO, a differential 122.88 MHz reference (TCXO), a loop filter, a USB interface, power supply connectors, and subminiature Version A (SMA) connectors. A USB cable is included to connect the board to a PC USB port. For easy programming of the synthesizer, download the Windows-based software from www.analog.com/ADF4355. This board requires an SDP-S (shown in Figure 1, but not supplied with the kit). The SDP-S allows software programming of the EV-ADF4355SD1Z device.

　　评估板EV-ADF4355SD1Z主要特性:

　　Self contained board, including ADF4355 frequency

　　synthesizer with integrated VCO, differential 122.88 MHz

　　temperature controlled crystal oscillator (TCXO), loop

　　filter (20 kHz), USB interface, and voltage regulators

　　Windows®-based software allows control of synthesizer functions from a PC

　　Externally powered by 6 V

　　图4.评估板EV-ADF4355SD1Z外形图

　　图5.评估板EV-ADF4355SD1Z电路图(1)

　　图6.评估板EV-ADF4355SD1Z电路图(2)

　　图7.评估板EV-ADF4355SD1Z电路图(3)

　　评估板EV-ADF4355SD1Z材料清单: