12-Bit, 3-MSPS A/D Converter Cleans Up Modems' Signals

High-speed DSL modem designs with cleaner signals over greater distances are made possible by the LTC1412, a 12-bit A/D converter that samples at a 3-MSPS rate with excellent dynamic specifications. The converter features a SINAD specification of 72 dB. And its high-speed parallel interface and bipolar ±2.5V input range make it well suited for telecommunication applications.Other features include internal or external reference operation and a 40-MHz bandwidth sample-and-hold that achieves outstanding ac performance beyond the Nyquist input frequency of 1.5 MHz. The chip's SAR architecture is inherently cleaner than pipelined architectures, even as it delivers the speed necessary for DSL applications. Operation is from ±5V supplies with an internal reference. The device also allows direct coupling to most high-performance op amps without special translation circuitry.