Analog Devices Inc. ADRF6655-EVALZ

Overview

ADRF6655-EVALZ from Analog Devices is an evaluation board for the ADRF6655 broadband up/downconverting mixer with integrated fractional-N PLL and VCO. It enables RF system validation of 100–2500 MHz RF input, 1050–2300 MHz internal LO generation, and differential 200 Ω IF output in both upconversion (e.g., 340 MHz RF → 1200 MHz IF) and downconversion (e.g., 1880 MHz RF → 140 MHz IF) modes. The board supports SPI programming, external loop filter configuration, and IP3SET bias optimization.

For engineers reviewing the ADRF6655-EVALZ datasheet, ADRF6655-EVALZ pinout, ADRF6655-EVALZ application, or ADRF6655-EVALZ equivalent, this board provides full access to all ADRF6655 control registers, calibrated RF/IF/LO paths, thermal grounding per JESD51-2, and documented layout practices for high-frequency mixer + synthesizer integration in wireless infrastructure and test equipment.

Technical Context

The ADRF6655-EVALZ implements the complete signal chain of the ADRF6655 IC: RF input via TC1-1-13M+ balun, LO path with VTUNE loop filter interface and LOP/LON access, differential IF output matched to 200 Ω using TC4-1W transformer, and SPI-controlled register bank (24-bit, 20 MHz max clock). All power domains (VCC1, VCC2, VCCLO, VCCMIX, VCCV2I) are independently decoupled with 100 pF / 0.1 µF / 10 µF networks per datasheet Figure 3 and Table 4.

It supports both high-side and low-side LO injection, external VCO operation, and dual-mode divider selection (÷2 or ÷3) for internal LO synthesis. The board includes MUXOUT routing for lock detect, temperature sensing (VPTAT), or scaled reference output - all configurable via Register 4 as defined in the ADRF6655 register map.

Key Specifications

Availability

ADRF6655-EVALZ is available at Aetrix Electronics and suitable for RF transceiver development, wireless infrastructure prototyping, and test equipment design requiring stable component supply, repeatable high-frequency characterization, and validated PLL/mixer co-design practices.

Supply support for ADRF6655-EVALZ 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, Inc. is a global leader in high-performance analog, mixed-signal, and RF ICs, serving communications, industrial, automotive, and instrumentation markets with precision signal processing solutions.

The ADRF6655-EVALZ belongs to Analog Devices' RF & Microwave Evaluation Platform family, designed specifically to accelerate time-to-test for highly integrated transceiver ICs combining active mixers, synthesizers, and digital control in single-chip architectures.

FAQ

What is the primary function of the ADRF6655-EVALZ?

The ADRF6655-EVALZ is an evaluation board for the ADRF6655 integrated broadband mixer and fractional-N PLL/VCO. It provides full hardware access to all ADRF6655 pins, calibrated RF/IF/LO signal paths, SPI programming interface, and thermal/mechanical implementation per datasheet specifications - enabling rapid validation of up/downconversion performance, PLL lock behavior, and system-level integration before custom PCB design.

Does the ADRF6655-EVALZ support both upconversion and downconversion testing?

Yes, the ADRF6655-EVALZ supports both modes. Downconversion is demonstrated with 1880 MHz RF input and 140 MHz IF output using 1740 MHz LO; upconversion uses 340 MHz RF input and 1200 MHz IF output with 1540 MHz LO. The board includes matching networks and baluns optimized for each mode per Figures 56 and 57 in the ADRF6655 datasheet.

How is the PLL on the ADRF6655-EVALZ configured and tuned?

The ADRF6655-EVALZ exposes VTUNE (Pin 39) for external loop filter connection and provides test points for REFIN (Pin 6), CP (Pin 3), and MUXOUT (Pin 8). PLL parameters - including PFD frequency (10–40 MHz), charge pump current (250–1000 µA), and integer/fractional divide values - are programmed via the 24-bit SPI interface to Registers 0–6 as defined in the ADRF6655 datasheet.

Can the ADRF6655-EVALZ be used with an external VCO instead of the internal one?

Yes. The ADRF6655-EVALZ supports external VCO operation via the LOP/LON pins (Pins 37/38), which accept 2×fLO or 3×fLO inputs depending on the selected divider mode. Register 7 controls external VCO enable/disable, and the board provides SMA connectors and AC-coupling capacitors compatible with standard VCO outputs per Section "Using an External VCO" in the ADRF6655 datasheet.

What power supply requirements does the ADRF6655-EVALZ have?

The ADRF6655-EVALZ requires a single 5 V supply (4.75–5.25 V) delivered to the board's main power header. Internally, it generates three regulated rails - 3.3 V (VCC1), 2.5 V (VCC2), and VCO LDO - per the ADRF6655's architecture. Total supply current ranges from 15 mA (power-down) to 310 mA (TX mode, IP3SET = 3.2 V, fLO ≤1530 MHz) as specified in Table 1 of the ADRF6655 datasheet.