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