GENERAL DESCRIPTION

The AD9878 is a single-supply, cable modem/set-top box, mixed-signal front end. The device contains a transmit path interpolation filter, a complete quadrature digital upconverter, and a transmit DAC. The receive path contains dual 12-bit ADCs and a 10-bit ADC. All internally required clocks and an output system clock are generated by the phase-locked loop (PLL) from a single crystal oscillator or clock input.

FEATURES

Low cost 3.3 V CMOS MxFE™ for broadband applications

DOCSIS, EURO-DOCSIS, DVB, DAVIC compliant

232 MHz quadrature digital upconverter

12-bit direct IF DAC (TxDAC+®)

Up to 65 MHz carrier frequency DDS

Programmable sampling clock rates

Analog Tx output level adjust

Dual 12-bit, 29 MSPS direct IF ADCs with video clamp input

10-bit, 29 MSPS sampling ADC

8-bit ∑-∆ auxiliary DAC

Direct interface to AD832x family of PGA cable drivers

APPLICATIONS

Cable set-top boxes

Cable and wireless modems