11-Oct-2011:- Analog Devices Inc. introduced a PLL (phase-locked loop) frequency synthesizer that can be used to implement local oscillators as high as 18 GHz in the up-conversion and down-conversion sections of wireless receivers and transmitters. The exceptionally high bandwidth of the ADF41020 allows designers to potentially eliminate a frequency-doubler stage, which simplifies system architecture and reduces cost in applications including microwave point-to-point and multi-point radios, wireless infrastructure equipment, VSAT (very small aperture terminal) radios, semiconductor test equipment, radar applications and private mobile radios.

Microwave PLL Frequency Synthesizer ADF41020 for Wireless Receivers and TransmittersThe ADF41020 PLL frequency synthesizer consists of a low noise, digital phase frequency detector, a precision charge pump, a programmable reference divider and high-frequency programmable feedback dividers. A complete synthesizer can be implemented if the PLL is used with an external loop filter and VCO (voltage controlled oscillator). The PLL can be used to drive external microwave VCOs via an active loop filter. The pin-out matches very closely the pinout of the ADF4106/7/8 family of integer-N PLLs, meaning only a minor layout change is required when updating a design to take advantage of the much wider bandwidth.

ADF41020 PLL Frequency Synthesizer Key Features

  • 18-GHz maximum RF input frequency
  • Integrated prescaler
  • Programmable dual-modulus prescaler
  • 2.7-V to 3.3-V PLL power supply
  • Programmable charge pump currents
  • 3-wire serial interface
  • Analog and digital lock detect
  • Hardware and software power-down mode