Analog Devices Inc. ADF4355BCPZ-RL7

Overview

ADF4355BCPZ-RL7 from Analog Devices is a microwave wideband fractional-N/integer-N PLL frequency synthesizer with integrated VCO, supporting RF output from 54 MHz to 6800 MHz. It features 38-bit frequency resolution, programmable output dividers (÷1/2/4/8/16/32/64), and dual-mode lock detection. Used in wireless infrastructure base stations for W-CDMA and WiMAX local oscillator generation.

For engineers reviewing the ADF4355BCPZ-RL7 datasheet, ADF4355BCPZ-RL7 pinout, ADF4355BCPZ-RL7 application, or ADF4355BCPZ-RL7 equivalent, key selection criteria include VCO frequency range (3400–6800 MHz), phase noise performance (−138 dBc/Hz @ 1 MHz offset, 3.4 GHz carrier), 3-wire SPI interface timing (50 MHz max CLK), and dual RF outputs (RFOUTA±/RFOUTB±) with independent mute control.

Technical Context

The ADF4355BCPZ-RL7 implements a third-order fractional interpolator with 38-bit modulus for ultra-fine frequency resolution and low in-band phase noise (−221 dBc/Hz normalized floor). Its dual-modulus prescaler (4/5 or 8/9) enables wide N-divider range while maintaining PFD frequencies up to 125 MHz.

It integrates a high-linearity VCO core with KV = 15 MHz/V and open-loop pushing/pulling of ≤15 MHz/V and ≤0.5 MHz respectively. Output stages support independent power programming and hardware/software RF mute via PDBRF pin and register control.

Key Specifications

Pinout & Package

The ADF4355BCPZ-RL7 is housed in a 32-lead LFCSP (5 mm × 5 mm, 0.5 mm pitch) with exposed thermal pad requiring connection to AGND.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar frequency synthesizer applications.

Compared with ADF4356BCPZ-RL7, the ADF4355BCPZ-RL7 trades 1.3 GHz upper-frequency margin for proven stability in 6 GHz-class infrastructure deployments; versus LMS8001-SYNTH, it delivers standalone synthesizer flexibility, wider bandwidth, and superior phase noise-critical for carrier-grade wireless systems.

Availability

ADF4355BCPZ-RL7 is available at Aetrix Electronics and suitable for wireless infrastructure, point-to-point microwave links, and satellite communication terminals requiring stable component supply across extended temperature ranges (−40°C to +85°C).

Supply support for ADF4355BCPZ-RL7 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices is a global leader in high-performance analog, mixed-signal, and RF ICs, serving precision instrumentation, communications, and industrial markets since 1965.

The ADF4355BCPZ-RL7 belongs to Analog Devices' ADF435x family of microwave PLL synthesizers, engineered specifically for carrier-grade wireless infrastructure and test equipment demanding ultra-low phase noise and wideband agility.

FAQ

What is the maximum RF output frequency supported by the ADF4355BCPZ-RL7?

The ADF4355BCPZ-RL7 supports an RF output frequency range of 54 MHz to 6800 MHz. This is achieved using its integrated VCO (3400–6800 MHz fundamental) followed by programmable dividers (÷1 to ÷64). At 6800 MHz, the device operates in fundamental VCO mode with ÷1 output; lower frequencies use division without external components. Performance data confirms −22 dBc third harmonic at 4.4 GHz and −12 dBc at divided outputs.

Does the ADF4355BCPZ-RL7 support both fractional-N and integer-N PLL modes?

Yes, the ADF4355BCPZ-RL7 natively supports both fractional-N and integer-N PLL operation. Its third-order fractional interpolator enables fine frequency resolution (sub-Hz steps) with normalized in-band phase noise floors of −221 dBc/Hz (fractional) and −223 dBc/Hz (integer). Mode selection is register-controlled; integer mode reduces fractional spurs but sacrifices resolution-ideal for fixed-frequency LOs in broadcast or radar.

How is RF output muting implemented on the ADF4355BCPZ-RL7?

The ADF4355BCPZ-RL7 provides dual RF mute capability: hardware control via the PDBRF pin (active-low) and software control via register bit. Both paths independently disable RFOUTA± and RFOUTB± outputs, reducing residual signal to −60 dBm (at 1 GHz) or −30 dBm (at 4.4 GHz). This feature enables fast TDD switching, power-saving sleep cycles, and isolation during calibration-without disrupting PLL lock state.

What are the power supply requirements for the ADF4355BCPZ-RL7?

The ADF4355BCPZ-RL7 requires three distinct supply domains: analog/digital core (AVDD/DVDD/VRF = 3.15–3.45 V), charge pump (VP = 4.75–5.25 V), and VCO (VVCO = 4.75–5.25 V). VP must equal VVCO. Each domain needs dedicated low-ESR decoupling (e.g., 100 nF + 10 nF ceramics) placed within 2 mm of respective pins. Grounds (AGND, CPGND, AGNDVCO, AGNDRF, SDGND) must be isolated on PCB and joined only at a single star point.

Can the ADF4355BCPZ-RL7 generate two independent RF outputs simultaneously?

Yes, the ADF4355BCPZ-RL7 provides two fully independent differential RF outputs: RFOUTA± and RFOUTB±. Each supports the full 54–6800 MHz range via internal dividers and has separate output power programming and mute control. They share the same VCO core but drive separate output stages-enabling dual-LO architectures (e.g., I/Q upconversion), diversity receivers, or redundant signal paths without external splitters or amplifiers.