Analog Devices Inc. AD8348-EVALZ

Overview

AD8348-EVALZ from Analog Devices is an evaluation board for the AD8348 broadband quadrature demodulator IC, supporting 50 MHz to 1000 MHz IF input and delivering I/Q baseband outputs with 75 MHz demodulation bandwidth, 44 dB linear-in-dB AGC range, and ±0.5° phase accuracy - used in W-CDMA, GSM, and LMDS receiver development.

For engineers reviewing the AD8348-EVALZ datasheet, AD8348-EVALZ pinout, AD8348-EVALZ application, or AD8348-EVALZ equivalent, this board enables rapid characterization of the AD8348's VGA-controlled demodulation performance, mixer linearity (IIP3 up to +28 dBm), noise figure (11 dB), and baseband amplifier interface to dual-channel ADCs such as AD9201 and AD9283.

Technical Context

The AD8348-EVALZ implements the full signal path of the AD8348 IC: differential LO input (760 MHz) drives a divide-by-2 phase splitter feeding two Gilbert-cell mixers; IF input (50–1000 MHz) passes through a 44 dB-range X-AMP® VGA before quadrature downconversion; baseband outputs (IMXO/QMXO → IAIN/QAIN → IOPP/IOPN & QOPP/QOPN) support direct connection to ADCs with user-configurable VCMO biasing.

Board-level features include on-board balun for single-ended LO drive, SMA connectors for IF/LO inputs and I/Q outputs, jumper-selectable VGA enable (ENVG), gain control voltage (VGIN) test points, offset nulling (IOFS/QOFS) capacitor pads, and decoupled 2.7–5.5 V supply rails - all optimized for evaluating demodulator accuracy, AGC settling (45 μs power-up), and spectral purity under real-world RF conditions.

Key Specifications

Availability

AD8348-EVALZ is available at Aetrix Electronics and suitable for wireless infrastructure prototyping, RF receiver design verification, and academic communications labs requiring stable component supply and documented evaluation platform support.

Supply support for AD8348-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 digital signal processing semiconductors, headquartered in Norwood, MA.

The AD8348-EVALZ belongs to Analog Devices' RF receiver evaluation platform family, designed specifically to accelerate development of high-linearity, wideband quadrature demodulators for cellular, point-to-point, and broadband wireless systems.

FAQ

What is the primary function of the AD8348-EVALZ?

The AD8348-EVALZ is an evaluation board for the AD8348 quadrature demodulator IC. It provides a complete, ready-to-use platform to characterize the AD8348's performance-including IF-to-baseband conversion, VGA gain control, I/Q accuracy, and ADC interface-using standard lab equipment. The AD8348-EVALZ does not operate standalone; it requires the AD8348 IC mounted and powered per its datasheet specifications.

Does the AD8348-EVALZ support both VGA-enabled and VGA-bypassed modes?

Yes, the AD8348-EVALZ supports both operational modes via the ENVG jumper. When ENVG is high, the AD8348's internal IF VGA is active (44 dB gain range); when ENVG is low, the VGA is bypassed and signals route directly through MXIP/MXIN inputs - allowing users to evaluate mixer-only performance or integrate external gain stages. This configuration is fully implemented and tested on the AD8348-EVALZ board.

Which ADCs are compatible with the AD8348-EVALZ baseband outputs?

The AD8348-EVALZ baseband outputs (IOPP/IOPN and QOPP/QOPN) are designed to interface directly with dual-channel ADCs requiring 2 V p-p differential input swing and VCMO-referenced biasing - specifically validated with AD9201, AD9283, and AD9218. Output common-mode voltage is set by the VCMO net, which can be tied to the onboard VREF (1 V) or driven externally, ensuring optimal dynamic range into these ADCs.

How is LO signal applied to the AD8348-EVALZ?

The AD8348-EVALZ accepts a 760 MHz single-ended LO signal via SMA connector J2, which feeds an on-board balun to generate the required differential 760 MHz drive for the AD8348's LOIP/LOIN pins. The board also supports direct differential LO injection at test points TP1/TP2 if external phase-matched sources are used - maintaining the AD8348's specified ±0.5° quadrature accuracy across 50–1000 MHz IF.

What power supply requirements does the AD8348-EVALZ have?

The AD8348-EVALZ requires a single 2.7 V to 5.5 V DC supply, delivered via screw terminal block P1. On-board decoupling (0.1 µF + 100 pF per VPOS rail) and dedicated ground planes (COM1/COM2/COM3) ensure stable operation per AD8348's absolute maximum ratings. Total enabled current draw is 38–58 mA at 5 V, dropping to 75 µA in standby - fully supported by the AD8348-EVALZ power architecture.