TI公司的ADS8484 是取样速率1.25MSPS的微功耗18位模数转换器,集成了4.096V基准电压和假双极全差分输入,18位基于电容的SAR ADC和取样与保持电路. ADS8484的工作电压从2.7V到5.25V,SNR为99dB,THD为-117dB,SFDR为120dB,在取样1.25MSPS时的功耗为235mW,有高速并行接口,可用在医疗设备,光网络,传感器接口,高精度数据采集系统和磁力计.本文介绍了ADS8484的主要特性,方框图, 应用电路, 单端输入差分输出配置图和差分输入差分输出配置图,以及评估板ADS848xEVM的主要特性,详细电路图和材料清单(BOM).

    ADS8484:18-BIT,1.25-MSPS,PSEUDO-BIPOLAR,FULLY DIFFERENTIAL INPUT, MICROPOWER SAMPLING ANALOG-TO-DIGITAL CONVERTER WITH PARALLEL INTERFACE,REFERENCE

    The ADS8484 is an 18-bit, 1.25-MSPS A/C converter with an internal 4.096-V reference and a pseudo-bipolar, fully differential input. The device includes a 18-bit capacitor-based SAR A/D converter with inherent sample and hold. The ADS8484 offers a full 18-bit interface, a 16-bit option where data is read using two read cycles, or an 8-bit bus option using three read cycles.

    The ADS8484 is available in a 48-lead 7x7 QFN package and is characterized over the industrial -40℃ to 85℃ temperature range.

    ADS8484主要特性:

    1.25-MHz Sample Rate

    ±1.5 LSB Typ, ±2.5 LSB Max INL

    +0.8/-0.6 LSB Typ, +1.5/-1 LSB Max DNL

    18-Bit NMC Ensured Over Temperature

    ±0.5-mV Offset Error

    TBD-PPM/℃ Offset Error Drift

    ±0.1 %FSR Gain Error

    ±TBD-PPM/℃ Gain Error Drift

    99dB SNR, -117db THD, 120dB SFDR

    Zero Latency

    Low Power: 235 mW Typ at 1.25 MSPS

    Pseudo-Bipolar Fully Differential Input Range: Vref to -Vref

    Onboard Reference with TBD PPM/℃ Drift

    Onboard Reference Buffer

    High-Speed Parallel Interface

    Wide Digital Supply 2.7 V to 5.25 V

    8-/16-/18-Bit Bus Transfer

    48-Pin 7x7 QFN Package

    ADS8484应用:

    Medical Instruments

    Optical Networking

    Transducer Interface

    High Accuracy Data Acquisition Systems