ADF4208BRUZ

Overview

The ADF4208BRUZ is a dual RF phase-locked loop (PLL) frequency synthesizer from Analog Devices, designed for local oscillator implementation in wireless transceivers. It integrates two independent synthesizers: an RF section (RF1) supporting up to 2.0 GHz and an IF section (RF2) supporting up to 1.1 GHz. The device operates on a single 2.7 V to 5.5 V supply with a typical current consumption of 14 mA at 3 V. Key internal components include a low-noise digital phase-frequency detector, selectable charge pump currents (1.25 mA or 5 mA), and dual modulus prescalers (32/33 or 64/65). Configuration is managed via a 3-wire serial interface.

Feature Summary

• Dual synthesizer architecture with RF1 input up to 2.0 GHz and RF2 input up to 1.1 GHz.
• Selectable charge pump currents of 1.25 mA or 5 mA for flexible loop filter design.
• Configurable dual modulus prescaler options: 32/33 or 64/65 for both RF sections.
• Integrated oscillator circuitry allowing reference input derivation from crystal oscillators.

Applications

• Wireless handsets (GSM, PCS, DCS, CDMA, WCDMA)
• Base stations for wireless radio systems
• Wireless LANs
• Communications test equipment

Procurement Notes

Verify the specific suffix 'BRUZ' corresponds to the TSSOP-20 package and industrial temperature range (-40°C to +85°C) as defined in the manufacturer's ordering guide. Confirm that the component requires external voltage-controlled oscillators (VCOs) and loop filters to complete the phase-locked loop circuit. Ensure power supply decoupling capacitors are placed close to the VDD and VP pins during assembly.

Selection Notes

Select the ADF4208BRUZ when dual synthesizers are required within a single package for compact transceiver designs. Choose this model over the ADF4206 if higher frequency operation up to 2.0 GHz is necessary for the RF1 section. Consider the selectable prescaler values (32/33 vs. 64/65) based on the desired division ratios and output frequency spacing requirements.

Part Context

The ADF4208 is part of the ADF420x family, which also includes the ADF4206 and ADF4207. While the ADF4206 supports frequencies up to 550 MHz for both sections, the ADF4208 extends the RF1 capability to 2.0 GHz. All devices in the family share similar control interfaces and architectural features, differing primarily in maximum operating frequencies.

Replacement Considerations

Public confirmed substitute part numbers: ADF4206BRUZ (for lower frequency applications).