GENERAL DESCRIPTION
The AD9877 is a single-supply set-top box and cable modem mixed-signal front end. The device contains a transmit path interpolation filter, complete quadrature digital upconverter, and transmit DAC. The receive path contains a 12-bit ADC and dual 8-bit ADCs. All internally required clocks and an output system clock are generated by the phase-locked loop (PLL) from a single crystal or clock input.

FEATURES
   Low cost 3.3 V CMOS MxFE™ for
      MCNS-DOCSIS-, DVB-, DAVIC-compliant
      set-top box and cable modem applications
   232 MHz quadrature digital upconverter
      12-bit direct IF DAC (TxDAC+®)
      Up to 65 MHz carrier frequency DDS
      Programmable sampling clock rates
      Selectable interpolation filter
      Analog Tx output level adjust
      12-bit, 33 MSPS direct IF ADC
   Dual 8-bit, 16.5 MSPS sampling IQ ADCs
   Two 12-bit Σ-Δ auxiliary DACs
   Direct interface to AD8321/AD8325 or
      AD8322/AD8327 PGA cable driver

APPLICATIONS
   Cable modems
   Set-top boxes
   Wireless modems