AD8322ARUZ-REEL

Overview

The AD8322ARUZ-REEL is a digitally controlled variable gain amplifier designed for coaxial line driving applications. It operates from a single 5 V supply with an operating range of 4.75 V to 5.25 V and draws 100 mA to 126 mA in power-up mode. The device provides a programmable gain range of 41.0 dB to 43.2 dB, scaling by 6.02 dB per major carry. It features a 180 MHz bandwidth and maintains a differential output impedance of 75 Ω ± 20% during both power-up and power-down states.

Feature Summary

• Digitally controlled variable gain amplifier optimized for DOCSIS reverse path transmission
• Maintains constant 75 Ω differential output impedance during power-up and power-down conditions
• Supports SPI interface for 8-bit serial gain control with low distortion performance
• Asynchronous power-down mode reduces quiescent current consumption significantly

Applications

• DOCSIS-compliant data modems for upstream transmission
• Gain programmable line drivers for CATV systems
• Interactive set-top boxes requiring precise signal level control
• PC plug-in modems utilizing coaxial cable interfaces
• General-purpose digitally controlled variable gain blocks

Procurement Notes

Verify component authenticity through authorized Analog Devices channels or certified distributors. Confirm the specific REEL packaging suffix matches design requirements. Check for obsolete status indicators as this part may be discontinued. Ensure ESD precautions are followed during handling due to sensitivity. Validate RoHS compliance documentation against current regulatory standards before integration.

Selection Notes

Select this component when a fixed 5 V supply is available and precise digital gain control is required. The internal 75 Ω output impedance simplifies PCB layout by eliminating external termination resistors. Consider the 180 MHz bandwidth sufficient for upstream cable modem frequencies up to 65 MHz. Evaluate thermal dissipation capabilities within the TSSOP-28 package for the expected power levels.

Part Context

This component belongs to the AD8322 family of CATV line drivers manufactured by Analog Devices. It is specifically engineered for low-cost implementation in cable modem architectures. The ARUZ suffix indicates a 28-lead TSSOP package suitable for surface mount assembly. The REEL designation specifies tape-and-reel packaging for automated placement processes.

Replacement Considerations

Public confirmed substitutes include the AD8323 for fine step output power control and the AD8326 for high output power applications. The AD8325 offers fine step control similar to the AD8323. Verify pin compatibility and gain step resolution differences when transitioning between these variants.