AD9868

Broadband Modem Mixed-Signal Front End AD9868 FEATURES Low cost 3.3 V CMOS MxFE for broadband modems 10-bit DAC converter 2×/4× interpolation filter 200 MSPS DAC update rate Integrated 17 dBm line driver with 19.5 dB gain control 10-bit, 80 MSPS, ADC converter −12 dB to +48 dB low noise RxPGA (<3 nV/√Hz) Third-order, programmable low-pass filter Flexible digital data path interface Half- and full-duplex operation Pin compatible with the AD9865 Various power-down/reduction modes Internal clock multiplier (PLL) 2 auxiliary programmable clock outputs Available in a 64-lead LFCSP_VQ FUNCTIONAL BLOCK DIAGRAM IOUTP+ IOUTP– AD9868 PWRDWN MODE TXEN/TXSYNC TXCLK/TXQUIET ADIO[9:4]/ Tx[5:0] 10 2-4X TxDAC 0 TO –7.5dB IAMP 0 TO –12dB IOUTN+ IOUTN– CLK SYNC. 2M CLK MULTIPLIER CLKOUT1 CLKOUT2 OSCIN XTAL ADIO[3:0]/ Rx[5:0] 10 RXEN/RXSYNC RXCLK AGC[5:0] PORT SPI PORT 6 06733-001 ADC 80MSPS 0 TO 6dB 2-POLE LPF RX+ 1-POLE LPF APPLICATIONS Broadband wireline networking RX– 4 REGISTER Δ = 1dB CONTROL –6 TO +18dB –6 TO +24dB Δ = 6dB Δ = 6dB Figure 1. www.DataSheet4U.com GENERAL DESCRIPTION The AD9868 is a mixed-signal front-end (MxFE®) IC for transceiver applications requiring Tx path and Rx path functionality with data rates up to 80 MSPS. A lower cost, pincompatible version of the AD9865, the AD9868 removes the current amplifier (IAMP) IOUTP functionality and limits the PLL VCO operating range of 80 MHz to 200 MHz. The part is well-suited for half- and full-duplex applications....