General Description
The MAX19708 is an ultra-low-power, mixed-signal analog front-end (AFE) designed for TD-SCDMA handsets and data cards. Optimized for high dynamic performance at ultra-low power, the device integrates a dual 10-bit, 11Msps receive (Rx) ADC; dual 10-bit, 11Msps transmit (Tx) DAC with TD-SCDMA baseband filters; three fast-settling 12-bit aux-DAC channels for ancillary RF front-end control; and a 10-bit, 333ksps housekeeping aux-ADC. The typical operating power in Tx-Rx FAST mode is 36.9mW at a 5.12MHz clock frequency.
The Rx ADCs feature 55dB SNR and 77.4dBc SFDR at a 1.87MHz input frequency with an 11MHz clock frequency. The analog I/Q input amplifiers are fully differential and accept 1.024VP-P full-scale signals. Typical I/Q channel matching is ±0.08° phase and ±0.02dB gain.

FEATUREs
♦ Dual 10-Bit, 11Msps Rx ADC and Dual 10-Bit,
   11Msps Tx DAC
♦ Ultra-Low Power
   36.9mW at fCLK = 5.12MHz, Fast Mode
   19.8mW at fCLK = 5.12MHz, Slow Mode
   Low-Current Standby and Shutdown Modes
♦ Integrated TD-SCDMA Filters with > 55dB
   Stopband Rejection
♦ Programmable Tx DAC Common-Mode DC Level
   and I/Q Offset Trim
♦ Excellent Dynamic Performance
   SNR = 55dB at fIN = 1.87MHz (Rx ADC)
   SFDR = 73dBc at fOUT = 620kHz (Tx DAC)
♦ Three 12-Bit, 1µs Aux-DACs
♦ 10-Bit, 333ksps Aux-ADC with 4:1 Input Mux and
   Data Averaging
♦ Excellent Gain/Phase Match
   ±0.08° Phase, ±0.02dB Gain (Rx ADC) at
   fIN = 1.87MHz
♦ Multiplexed Parallel Digital I/O
♦ Serial-Interface Control
♦ Versatile Power-Control Circuits
   Shutdown, Standby, Idle, Tx/Rx Disable
♦ Miniature 48-Pin Thin QFN Package
   (7mm x 7mm x 0.8mm)

APPLICATIONs
   TD-SCDMA Handsets
   TD-SCDMA Data Cards
   Portable Communication Equipment