AD8321ARZ-REEL

Overview

The AD8321ARZ-REEL is a digitally controlled variable gain amplifier optimized for coaxial line driving. It operates from a single +9 V supply and provides a linear-in-dB gain range of 53.4 dB with 0.7526 dB/LSB resolution via an SPI-compatible interface. The device maintains a constant 75 Ω output impedance during power-up and power-down states, eliminating the need for external matching components. It supports differential or single-ended inputs and delivers low distortion performance.

Feature Summary

• Digitally programmable gain control over a 53.4 dB range using an 8-bit serial word
• Maintains constant 75 Ω output impedance during both active and power-down modes
• Integrated reverse amplifier enables low-power operation when powered down
• Supports SPI-compatible digital interface for gain adjustment

Applications

• Gain programmable line drivers for cable modems
• HFC high-speed data modem upstream paths
• Interactive CATV set-top boxes
• CATV plant test equipment
• General purpose IF variable gain blocks

Procurement Notes

Verify component authenticity through authorized Analog Devices distributors or direct manufacturer channels. Confirm package integrity and pin alignment upon receipt. Ensure proper ESD handling procedures are followed during storage and assembly to prevent damage to the sensitive internal circuitry.

Selection Notes

Select this component for applications requiring precise digital gain control in RF signal chains. It is specifically suited for DOCSIS-compliant cable modem designs where maintaining 75 Ω impedance across varying gain settings is critical. Ensure the system design accommodates the required +9 V single supply voltage and provides adequate decoupling for stable operation.

Part Context

This part belongs to the AD8321 family of variable gain amplifiers manufactured by Analog Devices Inc. It is designed as a cost-effective solution for driving coaxial cables in broadband communication systems. The REEL suffix indicates the component is supplied in tape-and-reel packaging for automated surface-mount assembly processes.

Replacement Considerations

Public documentation identifies the AD8321AR as a compatible alternative within the same product family. Verify that any substitute maintains the required 53.4 dB gain range, 75 Ω output impedance, and SPI compatibility to ensure functional equivalence in existing designs.