GENERAL DESCRIPTION
The AD8322 is a low-cost, digitally controlled variable gain amplifier optimized for coaxial line driving applications such as cable modems that are designed to the MCNS-DOCSIS upstream standard. An 8-bit serial word determines the desired output gain over a 42.14 dB range, with gain steps of 6.02 dB/major carry.

FEATURES
   Supports DOCSIS Standard for Reverse Path
      Transmission
   Gain Programmable in 6 dB Steps Over a 42 dB
      Range
   Low Distortion at 60 dBmV Output
      –58 dBc SFDR at 21 MHz
      –56 dBc SFDR at 42 MHz
   Output Noise Level
      –46 dBmV in 160 kHz Bandwidth
   Maintains 75 Ω Output Impedance
      Power-Up and Power-Down Condition
   180 MHz Bandwidth
   5 V Supply Operation
   Supports SPI Interfaces

APPLICATIONS
   Gain Programmable Line Driver
   DOCSIS-Compliant Data Modems
   Interactive Set-Top Boxes
   PC Plug-in Modems
   General-Purpose Digitally Controlled Variable Gain Block