ADF4208BRUZ-R7

Overview

The ADF4208BRUZ-R7 is a dual RF PLL frequency synthesizer from Analog Devices, designed for local oscillator implementation in wireless transceivers. It features two independent synthesizers: RF1 operating up to 2.0 GHz and RF2 (IF) up to 1.1 GHz. The device supports a supply voltage range of 2.7 V to 5.5 V with selectable charge pump currents (1.25 mA or 5 mA). Key internal components include a digital phase frequency detector, programmable counters (R, A, B), and a dual modulus prescaler (32/33 or 64/65). It utilizes a 3-wire serial interface for control and includes power-down capabilities.

Feature Summary

• Dual synthesizers with RF1 input up to 2.0 GHz and IF input up to 1.1 GHz
• Selectable dual modulus prescaler options: 32/33 or 64/65 for both channels
• Configurable charge pump currents: 1.25 mA (low) or 5 mA (high)
• Integrated on-chip oscillator circuitry for crystal reference inputs

Applications

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

Procurement Notes

Verify the specific suffix '-R7' indicates reel packaging when sourcing. Confirm the 'B' grade designation corresponds to the industrial temperature range of -40°C to +85°C. Ensure compatibility with the 20-lead TSSOP package outline for PCB layout. Cross-reference the datasheet revision to confirm pinout consistency.

Selection Notes

Select this model over the ADF4206 if higher frequency coverage is required, specifically for RF1 signals up to 2.0 GHz. The ADF4208 provides an IF section capable of handling frequencies up to 1.1 GHz. Consider the selectable prescaler values (32/33 vs 64/65) based on the desired division ratios and loop bandwidth requirements for the target application.

Part Context

This component belongs to the ADF420x family of dual frequency synthesizers, which also includes the ADF4206 and the discontinued ADF4207. The ADF4208 variant is distinguished by its extended upper frequency limits for both the RF and IF sections compared to the ADF4206. It shares the same architectural foundation, including the 3-wire interface and low-noise PFD design.

Replacement Considerations

The ADF4206BRUZ-R7 is a functional substitute within the same family but offers lower maximum input frequencies (0.55 GHz for RF1 and IF). Direct replacement requires verifying that the system's frequency requirements do not exceed the ADF4206's specifications.