Analog Devices Inc. ADF535x Microwave Wideband Synthesizers

Analog Devices ADF535x Microwave Wideband Synthesizers integrate fractional-N or integer-N phase-locked loop (PLL) frequency synthesizers when combined with an external loop filter and an external reference frequency. Using a series of frequency dividers, ADF535x can operate from 53.125MHz to 6800MHz. The ADF535x synthesizers include an integrated VCO with a 3400MHz-6800MHz fundamental output frequency. 

Designers can divide the VCO frequency by 1, 2, 4, 8, 16, 32, or 64 circuits to generate RF output frequencies down to 53.125MHz. The ADF535x's wideband, microwave VCO design enables 6.8GHz to 13.6GHz operation at one RF output. The ADF535x synthesizers operate using 3.15V to 3.45V analog and digital power supplies. The synthesizers also use a 4.75V-5.25V charge pump and VCO supplies. If an application requires isolation, designers can mute the RF output stage. The designers can also control the on-chip registers using a simple 3-wire interface.


  • RF output frequency range: 53.125MHz to 13.6GHz
  • Fractional-N synthesizer and integer-N synthesizer
  • High-resolution 38-bit modulus and 52-bit modulus
  • Phase frequency detector (PFD) operation to 125MHz
  • Reference frequency operation to 600MHz
  • Maintains frequency lock over −40°C to 85°C
  • Low phase noise, voltage controlled oscillator (VCO)
  • Programmable divide by 1, 2, 4, 8, 16, 32, or 64 output
  • Analog and digital power supplies: 3.3V
  • Charge pump and VCO power supplies: 5V, typical
  • Logic compatibility: 1.8V
  • Programmable dual modulus prescaler of 4/5 or 8/9
  • Programmable output power level
  • RF output mute function
  • Analog and digital locks detect
  • Supported in the ADIsimPLL design tool


  • Wireless infrastructure (LTE, W-CDMA, TD-SCDMA, WiMAX, GSM, PCS, DCS, DECT)
  • Point to point/point to multipoint microwave links
  • Satellites and Very Small Aperture Terminals (VSATs)
  • Test equipment/instrumentation
  • Clock generation
Published: 2016-08-29 | Updated: 2022-03-11