基于ADS1298設計的8路24位精度心電圖(ECG)前端技術摘要：實現了一種全集成可變帶寬中頻寬帶低通濾波器，討論分析了跨導放大器-電容(OTA—C)連續時間型濾波器的結構、設計和具體實現，使用外部可編程電路對所設計濾波器帶寬進行控制，并利用ADS軟件進行電路設計和仿真驗證。仿真結果表明，該濾波器帶寬的可調范圍為1～26MHz，阻帶抑制率大于35dB，帶內波紋小于0．5dB，采用1．8V電源，TSMC0．18μmCMOS工藝庫仿真，功耗小于21mW，頻響曲線接近理想狀態。關鍵詞：ButteADS1298集成了心電圖(ECG)前端的8路24位精度delta-sigma(ΔΣ)模/數轉換器,具有同時取樣和內置的可編增益放大器(PGA),基準電壓和振蕩器,包含了醫療心電圖(ECG)和腦電圖(EEG)所有的功能.本文介紹了ADS1298主要特性和優勢,功能方框圖,以及每路輸入復接器方框圖,單電源連接框圖,雙電源連接框圖與心電圖(ECG)總體方框圖.

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主要特性和優勢:

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應用:

?MedicalInstrumentation(ECGandEEG)including:

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

fetalECG

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

?High-Precisio