NS ADC083000 3GSPS ADC应用方案

liyf

                    　　NS公司的ADC083000是8位取样速率高达3.4GSPS高性能低功耗的模数转换器（ADC），1.9V电源和取样3GSPS时的功耗为1.9W。ADC083000在整个工作温度范围不会丢失码，广泛应用在直接RF下变换，数字示波器，卫星机顶盒，通信系统和测试仪表。本文介绍了ADC083000 3GSPS ADC的主要性能，方框图，应用以及评估板详细电路图。

??????? ADC083000 8-Bit, 3 GSPS, High Performance, Low Power A/D Converter

??????? 概述：

??????? The ADC083000 is a single, low power, high performance CMOS analog-to-digital converter that DIGItizes signals to 8 bits resolution at sAMPling rates up to 3.4 GSPS. Consuming a typical 1.9 Watts at 3 GSPS from a Single 1.9 Volt supply, this device is guaranteed to have no missing codes over the full operating temperature range. The unique folding and interpolating architecture, the fully differential comparator design, the innovative design of the internal sample-and-hold amplifier and the self-calibration scheme enable a very flat response of all dynamic parameters up to Nyquist, producing a high 7.0 Effective Number Of Bits, (ENOB) with a 748 MHz
input signal and a 3 GHz Sample Rate while providing a 10-18 Bit Error Rate, (BER). The ADC083000 achieves a 3 GSPS sampling rate by utilizing both the rising and falling edge of a 1.5 GHz input clock. Output formatting is offset binary and the LVDS Digital outputs are compatible with IEEE 1596.3-1996, with the exception of an adjustable common mode voltage between 0.8V and 1.15V.

??????? The ADC has a 1:4 demultiplexer that feeds four LVDS buses and reduces the output data rate on each bus to a quarter of the sampling rate. The converter typically consumes less than 25 mW in the Power Down Mode and is available in a 128-lead, thermally enhanced exposed pad LQFP and operates over the Industrial (-40°C ≤ TA ≤ +85°C) temperature range.

??????? 主要特性：

??????? ■ Internal Sample-and-Hold
??????? ■ Single +1.9V ±0.1V Operation
??????? ■ Choice of SDR or DDR output clocking
??????? ■ Guaranteed No Missing Codes
??????? ■ Serial Interface for Extended Control
??????? ■ Adjustment of Input Full-Scale Range and Offset
??????? ■ Duty Cycle Corrected Sample Clock
??????? ■ Test pattern

??????? 主要指标：
??????? ■ Resolution 8 Bits
??????? ■ Max Conversion Rate 3 GSPS (min)
??????? ■ Bit Error Rate (BER) 10-18 (typ)
??????? ■ ENOB @ 748 MHz Input 7.0 Bits (typ)
??????? ■ SNR @ 748 MHz 44.5 dB (typ)
??????? ■ Full Power Bandwidth 3 GHz (typ)
??????? ■ Power Consumption
??????? — Operating 1.9 W (typ)
??????? — Power Down Mode 25 mW (typ)

??????? 应用：
??????? ■ Direct RF Down Conversion
??????? ■ Digital Oscilloscopes
??????? ■ Satellite Set-top boxes
??????? ■ Communications Systems
??????? ■ Test Instrumentation
??????? ADC083000方框图：







??????? 以下是评估板的电路图：







图2。评估板电路图（2）







?????????????????????????????????????????????????????????????????????????? 图4。评估板电路图（4）







?????????????????????????????????????????????????????????????? 图6。评估板电路图（6）







?????????????????????????????????????????????????????????????????????????????????? 图7。评估板电路图（7）