AD8325ARUZ

Overview

The AD8325ARUZ is a digitally controlled variable gain amplifier optimized 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 133 mA in transmit enable mode. The device provides a programmable gain range of 59.45 dB, scaled at 0.7526 dB per LSB via an 8-bit serial interface. It maintains a differential output impedance of 75 Ω ± 20% across all gain settings and supports SPI interfaces.

Feature Summary

• Digitally controlled variable gain amplifier with 0.75 dB step resolution over a 59.45 dB range
• Maintains constant 75 Ω differential output impedance during both transmit enable and disable modes
• Integrated sleep mode reduces quiescent current to approximately 4 mA
• Supports DOCSIS standard for reverse path transmission with low distortion performance

Applications

• DOCSIS high-speed data modems
• Interactive cable set-top boxes
• PC plug-in cable modems
• Gain-programmable line drivers

Procurement Notes

Verify the specific ordering suffix against official Analog Devices documentation to confirm package type and lead-free status. Confirm that the component meets RoHS compliance requirements for the intended application. Check for any recent product change notices or lifecycle status updates directly from the manufacturer before finalizing procurement plans.

Selection Notes

Select this component for upstream power amplification in cable modem designs requiring precise digital gain control. Ensure the design accommodates the 5 V single-supply requirement and the 133 mA typical current consumption. Verify that the PCB layout supports the required decoupling capacitors and ground plane connections to maintain signal integrity and thermal performance within the specified temperature range.

Part Context

The AD8325ARUZ belongs to the AD8325 family of special purpose amplifiers manufactured by Analog Devices. It is specifically engineered as a CATV line driver with fine-step output power control capabilities. The ARUZ designation indicates a Pb-free version housed in a 28-lead TSSOP package, suitable for surface-mount assembly in compact electronic devices.

Replacement Considerations

Publicly confirmed substitutes include the MA/COM ETC-1-IT-15 transformer for output coupling tasks. For direct functional replacement, verify compatibility with other AD8325 variants such as the AD8325ARU or reel-packaged versions like the AD8325ARUZ-REEL, ensuring pinout and electrical specifications remain identical.