基于ADS1298设计的8路24位精度心电图(ECG)前端技术

基于ADS1298设计的8路24位精度心电图(ECG)前端技术摘要：实现了一种全集成可变带宽中频宽带低通滤波器，讨论分析了跨导放大器-电容(OTA—C)连续时间型滤波器的结构、设计和具体实现，使用外部可编程电路对所设计滤波器带宽进行控制，并利用ADS软件进行电路设计和仿真验证。仿真结果表明，该滤波器带宽的可调范围为1～26MHz，阻带抑制率大于35dB，带内波纹小于0．5dB，采用1．8V电源，TSMC0．18μmCMOS工艺库仿真，功耗小于21mW，频响曲线接近理想状态。关键词：ButteADS1298集成了心电图(ECG)前端的8路24位精度delta-sigma(ΔΣ)模/数转换器,具有同时取样和内置的可编增益放大器(PGA),基准电压和振荡器,包含了医疗心电图(ECG)和脑电图(EEG)所有的功能.本文介绍了ADS1298主要特性和优势,功能方框图,以及每路输入复接器方框图,单电源连接框图,双电源连接框图与心电图(ECG)总体方框图.

8-Channel,24-BitAnalog-To-DigitalConverterWithIntegratedECGFrontEnd

TheADS1294/6/8areafamilyofmultichannel,simultaneoussampling,24-bit,delta-sigma(ΔΣ)analog-to-digitalconverters(ADCs)withabuilt-inprogrammablegainamplifier(PGA),internalreference,andanonboardoscillator.TheADS1294/6/8incorporateallofthefeaturesthatarecommonlyrequiredinmedicalelectrocardiogram(ECG)andelectroencephalogram(EEG)applications.

ADS1298主要特性和优势:

Simplifiesdesignandsavesboardspace,usingupto95percentfewercomponents,byintegratingallcommonfeaturesrequiredforECGandEEGfrontends,includingthefollowing:

eightlow-noiseprogrammablegainamplifiers(PGAs).

eighthigh-resolution,simultaneoussamplinganalog-to-digitalconverters(ADCs).

integratedamplifierforright-legdrive.

integratedamplifiersforWilsonCentralTerminal(WCT)andGoldbergerTerminals(GCT).

digitalpacedetectioncapability.

continuouslead-offdetection.

onboardoscillatorandreferenceforsmallerfootprintandlow-powerapplications.

Powerconsumptionof1mW/channelresultsinupto95percentlesspowerusethandiscreteimplementations,increasingequipmentportabilityandimprovingpatientmobility.

TheADS1298’s4-uVpp(typical)input-referrednoiseisfarsuperiortothelimitssetinIEC60601-2-27/51,formoreaccuratemeasurementsinportableequipmentandhighchannel-density,high-endECGandEEGequipment.

Complementingtheanalogfrontend’sleadingpowerconsumptionisthelow-powerTMS320C5505DSPfamily.Atlessthan0.15-mW/MHzpowerconsumption,theTMS320C5505maximizesbatterylifeforportablepatientmonitoringapplications.TogetherwithTI’sfullportfolioofanalogsignalchainandpowermanagementsolutions,thesedevicesoffercustomersacompletesignalchainforECGandEEGapplicationstospeedtheirtimetomarket.

ADS1298应用:

•MedicalInstrumentation(ECGandEEG)including:

–Patientmonitoring;Holter,event,stress,andvitalsignsECG,AED,telemedicine,

fetalECG

–Bispectralindex(BIS),Evokedaudiopotential(EAP),Sleepstudymonitor

•High-Precisio