微波宽带频率合成器解决专项方案.doc

ADI ADF4355微波宽带(54－6800 MHz)频率合成器解决方案
ADI公司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)频率合成器,高辨别率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,模仿和数字电源为3.3 V,重要用在无线基本设施（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.本文简介了ADF4355重要特性,框图和几种应用电路,以及评估板EV-ADF4355SD1Z重要特性,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重要特性:

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 .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重要特性:

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:

图8.评估板EV-ADF4355SD1Z PCB设计图(1)

图9.评估板EV-ADF4355SD1Z PCB设计图(2)

图10.评估板EV-ADF4355SD1Z PCB设计图(3)

图11.评估板EV-ADF4355SD1Z PCB设计图(4)

图12.评估板EV-ADF4355SD1Z PCB设计图(5)

图13.评估板EV-ADF4355SD1Z PCB设计图(6)