Yuav ua li cas diodes tiv thaiv kev sojntsuam circuits hauv cov khoom siv kho mob ultrasound?

Ib, Kev tiv thaiv yooj yim: Thaiv rov qab tam sim no thiab voltage spikes
1. Rov qab kev sib cais tam sim no thiab kev tiv thaiv rov qab
Ultrasound sojntsuam txais ntau lub ntsiab lus sib xyaw ua ke thiab kev txais tos, tsuas yog qee lub ntsiab lus koom nrog hauv txhua qhov haujlwm. Hauv kev tsim qauv, ntau pua ntawm cov xov hlau yuav tsum tau nruab nrab ntawm kev sojntsuam thiab tus tswv tsev, thaum cov khoom siv niaj hnub no txo ​​cov xov hlau mus rau kaum ob los ntawm diode hloov matrix. Piv txwv li, EUB-240 B-ultrasound siv 16 kis / tau txais circuits thiab ua tiav kev xaiv excitation ntawm array ntsiab los ntawm diode array. Lub diode ua lub luag haujlwm unidirectional coj hauv qhov xwm txheej no:

Launch theem: High voltage pulses them tus sojntsuam array ntsiab los ntawm diodes, tsim ultrasonic tsis;
Tau txais theem: Lub diode raug tua nyob rau hauv thim rov qab los tiv thaiv tsis muaj zog ncha teeb liab los ntawm kev hloov pauv los ntawm kev xa xov hluav taws xob.
Qhov kev tsim no zam kev rov qab mus rau qhov kev sojntsuam thaum lub zog loj tsis ua haujlwm, tiv thaiv lub piezoelectric nti los ntawm qhov cuam tshuam rov qab. Schottky diodes (xws li BAT85) tau dhau los ua qhov kev xaiv zoo tshaj plaws rau siab - zaus sojntsuam circuits vim lawv qhov qis qis rau pem hauv ntej poob (0.15-0.45V) thiab nanosecond rov qab lub sijhawm.

2. Transient Voltage Suppression (TVS)
Thaum lub sijhawm ntawm cov khoom siv ultrasound pib lossis kev sojntsuam hloov pauv, qhov hluav taws xob ntawm ntau pua volts yuav raug tsim tawm hauv Circuit Court. TVS diodes clamp lub voltage mus rau ib qho kev nyab xeeb nyob rau hauv picoseconds los ntawm avalanche tawg nyhuv. Piv txwv li:

SSD-256 yam khoom siv: cov khoom sib txuas TVS nyob rau hauv kev sib kis / txais tos hloov hluav taws xob kom nqus cov hluav taws xob rov qab;
Wireless sojntsuam tsim: Siv SiC TVS diodes, nws tuaj yeem tiv taus qhov kub thiab txias ntawm -200℃txog 500℃thiab hloov mus rau qhov chaw huab cua.
Lub clamping voltage (Vc) thiab peak pulse tam sim no (Ipp) tsis tau ntawm TVS raj yuav tsum tau ua kom raug raws li kev sojntsuam tiv thaiv qhov ntsuas hluav taws xob kom ntseeg tau tias muaj kev tiv thaiv zoo hauv ESD (electrostatic paug) lossis xob laim induction scenarios.

2, Dynamic adjustment: optimizing teeb liab zoo thiab lub zog efficiency
1. Kev tsim kho ntawm qhov siv hluav taws xob siv hluav taws xob siv hluav taws xob tswj hluav taws xob diode
Ultrasonic sojntsuam txais Circuit Court yuav tsum muaj siab -precision reference voltage los xyuas kom meej cov teeb liab kev ruaj ntseg. Zener diodes (xws li 1N4742A) muab qhov kev siv hluav taws xob nrog nanometer qib raug (± 0.1%) los ntawm cov nyhuv Zener, thiab lawv cov dynamic tsis kam (Rz) tsawg li 0.1 Ω, kom ntseeg tau tias cov zis fluctuation tsawg dua 0.1% thaum lub load tam sim no hloov. Hauv ECG saib xyuas module, kev sib xyaw ua ke ntawm lub zog tswj hluav taws xob diode thiab lub tshuab ua haujlwm ua haujlwm tuaj yeem tshem tawm qhov cuam tshuam ntawm lub zog hluav taws xob nrov ntawm cov teeb liab electrocardiogram tsis muaj zog.

2. Zoo tagnrho diode maub los tshem tawm voltage poob poob
Ib txwm diode conduction voltage poob (0.3-}0.7V) tuaj yeem ua rau muaj kev siv hluav taws xob tseem ceeb hauv cov hluav taws xob qis qis. Qhov zoo tshaj plaws diode maub los (xws li LTC4412) simulates lub diode muaj nuj nqi los ntawm ib tug sab nraud MOSFET, txo qhov conduction voltage poob rau hauv qab no 10mV, thaum tseem muaj kev tiv thaiv rov qab, tshaj kub kaw, thiab raws li txoj cai indications functions. Hauv cov khoom siv ultrasound portable, cov thev naus laus zis no txhim kho kev ua haujlwm ntawm 3.3V tshuab los ntawm 15% thiab txuas ntxiv roj teeb lub neej.

3, Tsim kev ntseeg siab: yoog raws cov kev cai nruj ntawm cov xwm txheej kho mob
1. Dav kub thiab hluav taws xob tiv thaiv qhov cuab lub zog
Cov cuab yeej siv hauv chav ua haujlwm yuav tsum ua haujlwm ruaj khov hauv ib puag ncig ntawm -20℃txog 50 degree, thiab qee yam khoom siv (xws li xov tooj cua kho qhov chaw ultrasound) yuav tsum tau tiv thaiv hluav taws xob. Kev kho mob qib diodes tau ua tiav los ntawm cov txheej txheem tshwj xeeb:

Iav passivation ntim (GP): txo cov xau tam sim no thiab txhim kho siab - qhov kub thiab txias;
Silicon carbide (SiC) khoom: Hauv CT cov cuab yeej X-ray detectors, SiC photodiodes tuaj yeem ua haujlwm ruaj khov ntawm 175℃thaum tiv thaiv hluav taws xob- cuam tshuam kev puas tsuaj.
2. Rov ua dua thiab ua txhaum - tsim qauv tsim
Nyob rau hauv ib tug dual fais fab mov system, diodes ua tiav tsis siv neeg lub hwj chim hloov thiab txhaum cais. Piv txwv li:

LOSSIS ing diode: saib xyuas cov xwm txheej ntawm cov khoom siv hluav taws xob tseem ceeb thiab cov khoom siv thaub qab, seamlessly hloov mus rau lub zog thaub qab thaum muaj lub zog loj tsis ua haujlwm, nrog lub sijhawm hloov ntawm tsawg dua 1 μs;
Kev sib cais ntau channel: Hauv 128 lub ntsiab lus sojntsuam, 128 ywj siab diode cais circuits yog siv los xyuas kom meej tias ib qho kev tsis ua haujlwm tsis cuam tshuam rau tag nrho cov duab.
4, Cov ntaub ntawv siv tshuaj ntsuam xyuas
Case 1: Da Vinci phais neeg hlau ultrasound sojntsuam
Da Vinci phais neeg hlau yog tsav los ntawm ntau lub cev muaj zog thiab yuav tsum muaj lub zog ruaj khov heev. Nyob rau hauv nws ultrasound sojntsuam Circuit Court:

Cov tswv yim kawg: TVS diode (SMAJ5.0A) suppresses transient overvoltage hauv daim phiaj fais fab;
Cov theem nruab nrab: Schottky diode (MBR1045CT) ua hauj lwm raws li ib tug freewheeling tivthaiv kom txo tau lub cev muaj zog rov qab electromotive quab yuam cuam tshuam;
Output davhlau ya nyob twg: Ideal diode maub los (LTC4412) paub txog kev hloov hluav taws xob tsis siv neeg thiab tshem tawm qhov poob qis.
Qhov kev tsim no ua kom ntseeg tau tias qhov kev hloov pauv ntawm qhov hluav taws xob tsawg dua 2% thaum lub sijhawm hloov pauv tam sim ntawd, kom ntseeg tau qhov tseeb ntawm kev txav ntawm caj npab robotic.

Case 2: Gradient amplifier rau MRI khoom
Lub gradient amplifier ntawm MRI cov cuab yeej xav tau los tsim kom muaj lub zog sib nqus, thiab nws cov khoom siv hluav taws xob ntsib teeb meem ntawm qhov hluav taws xob siab thiab tam sim no. Cov kev tiv thaiv tseem ceeb muaj xws li:

Fast Recovery Diode (FRD): xws li MUR1560, nrog lub sij hawm rov qab los ntawm tsawg dua 50ns, suppresses thim rov qab high voltage thaum lub sij hawm inductor coil hloov;
Zener diode array: muab qhov kev siv hluav taws xob ruaj khov rau kev tswj xyuas Circuit Court, tsis txhob teeb liab distortion los ntawm magnetic teb fluctuations.
Los ntawm cov qauv tsim saum toj no, gradient amplifier tuaj yeem ua tiav qhov tseeb ntawm ± 0.1%, kom ntseeg tau cov duab daws teeb meem.