Univrsità dgli Studi di atania Facoltà di Inggnria Dipartimnto di Inggnria Elttrica Elttronica di Sistmi Rsidnc Tims Diffrnc (RTD) - Fluxgat Magntomtr Ing.. arlo Trigona A.A. 007/ Outlin lassification of magntomtrs Magntomtrs for biomdical applications RT-Fluxgat Working principl Exprssions of RTD and Snsitivity Fluxgat tchnology PB FR4 Wir Magntic particls and biosystms St-up Rsults Volcanic ash dtction St-up Rsults onclusion arlo Trigona A.A. 007-
Magntomtrs: classification Magntic fild snsors Vctor H < 1mT Magntomtrs Scalar SQUID Proton prcssion Fluxgat Optically pumpd Magntorsistanc H > 1mT Gaussmtrs Hall ffct Magntorsistiv Magntodiod Magntotransistor arlo Trigona A.A. 007- Magntomtrs: biomdical applications Magntorsistanc HTS SQUID (77 K) LTS SQUID (4. K) Fluxgat (300 K) 10-15 10-1 10-9 10-6 [T] Brain Hart Magntic immunoassay Earth fild arlo Trigona A.A. 007-
Magntomtrs: biomdical applications Magntorsistanc HTS SQUID (77 K) LTS SQUID (4. K) Fluxgat (300 K) 10-15 10-1 10-9 10-6 [T] Brain Hart Magntic immunoassay Earth fild arlo Trigona A.A. 007- Fluxgat vs. SQUID Fluxgat SQUID Rang [T]: 10-10 to 10-4 Rsolution [pt]: 100 Bandwidth: dc to x 10 3 Hz Low cost Low powr Robust and simpl systm Oprativ tmpratur: -50 to +80 Small siz and wight Rang [T]: 10-15 to 10-4 Rsolution [pt]: 0.1 Bandwidth: dc to 5 Hz High cost Low nois omplx systm Oprativ tmpratur: cryognic Sophisticatd applications arlo Trigona A.A. 007-
RTD-Fluxgat Vout (V) 0.5 0.4 0.3 0. 0.1 0-0.1-0. -0.3-0.4-0.5 T + T - 0 000 4000 6000 8000 1000 N (sampls) U x x + H + Hx k ( x, t) = k ln cosh dx τ dt x + H + Hx U ( x, t) = x + tanh k x arlo Trigona A.A. 007- RTD-Fluxgat RTD= T + -T - Rsidnc Tim Diffrnc Bias signal Hc -Hc +Msat -Msat Fluxgat output wavform Tim arlo Trigona A.A. 007-
RTD-Fluxgat Th principl of RTD Fluxgat is to xploit th information carrid by th tim position of spiks in th Vout signal. Tim intrvals, T+ and T-,, dfind by two succssiv paks rprsnt tims spnt by th cor magntization in th two stady stats. Ths tim intrvals ar calld Rsidnc Tims. Th Rsidnc Tim Diffrnc is th quantity RTD= T+ - T-. arlo Trigona A.A. 007- RTD-Fluxgat If w considr th tims: : t 1, t, t 3, it s possibl to writ: ( t1 ) ( t ) t1 : H + H = H t : H + H = H t3 = t1 +τ Wrting th quations in th cas of a sinusoidal bias signal of amplitud and frquncy 1 w obtain: Ĥ H H Invrting th functions w hav th xprssions: τ + Hˆ Hˆ sin ( ωt ) 1 = H τ sin ω t = H τ and sin ω t sin( ωt 1 ) arlo Trigona A.A. 007-
RTD-Fluxgat t t t 1 3 1 H H = arcsin ω Hˆ 1 H + = H arcsin ω Hˆ 1 H = arcsin ω H Hˆ τ + + τ T T + = t = t 3 t 1 t 1 H arcsin + H = ω ˆ H 1 H = arcsin ω H Hˆ H arcsin H Hˆ H + arcsin H ˆ H Th xprssions of Rsidnc Tim diffrnc and Snsitivity ar: + H + = = H RTD T T arcsin ω Hˆ 1/ Hˆ S = RTD = Hc + Hx 1 Hx ω ˆ H arlo Trigona A.A. 007- H H arcsin Hˆ 1/ Hˆ + Hc Hx 1 ˆ H τ + τ + Fluxgat: : PB FR4 tchnology Th pattrnd Mtglas is alignd rspct th two FR4 layrs Th pattrnd mtal layrs ar alignd to th structur according to layout dsign Finally th vias formation btwn th lowr and uppr layr lt to complt th windings for th coils Th whol fiv layrs ar prssd, whil hating th whol systm up to 00 Mtglas or arlo Trigona A.A. 007-
Fluxgat: : PB FR4 tchnology FR4 tchnology Snsibility: : 0.µs/nT Nois lvl: 5µs5 Absorbd currnt: 40 mapp arlo Trigona A.A. 007- Fluxgat: : PB FR4 tchnology haractrization 10 D Magntic shild Solnoid Fluxgat Rsolution [nt] 9 8 7 6 5 4 3 1 0 0 10 0 30 40 50 6 Obsrvation Tim [s] 5 Th Automatic calibration systm has bn implmntd with a st of instrumnt drivn by labviw Th RTD has bn calculatd by post laborat th output signals with MatLab Snsitivity [us/nt] 4 3 1 0 0 10 0 30 40 50 Obsrvation Tim [s] arlo Trigona A.A. 007-
Fluxgat: : PB FR4 tchnology haractrization D Magntic shild Solnoid Fluxgat Th Automatic calibration systm has bn implmntd with a st of instrumnt drivn by labviw Th RTD has bn calculatd by post laborat th output signals with MatLab arlo Trigona A.A. 007- Fluxgat: : wir wir tchnology or: 100 µm wir tchnology can b usd to localiz micro-ntitis and punctual magntic fild oils: : 100 µm arlo Trigona A.A. 007-
Fluxgat: : wir wir tchnology Primary: : 30+30 coils Scondary: 60 coils Primary: : 1000 coils Scondary: 1000 coils arlo Trigona A.A. 007- Fluxgat: : wir wir tchnology haractrization Th Automatic calibration systm has bn implmntd with a st of instrumnt drivn by labviw Th RTD has bn calculatd by post laborat th output signals with MatLab arlo Trigona A.A. 007-
Fluxgat: : wir wir tchnology haractrization Th Automatic calibration systm has bn implmntd with a st of instrumnt drivn by labviw Th RTD has bn calculatd by post laborat th output signals with MatLab arlo Trigona A.A. 007- Magntic particls: Immuno-assay Antibody Magntic or Dtction tchniqus Rmannc of magntic particls Rlaxation tim of magntic particls arlo Trigona A.A. 007-
Magntic particls: Immuno-assay arlo Trigona A.A. 007- Magntic particls: : M-10 10-10 Sphrotch Diamtr: : 1 1.41 1.4 µm unit: 10ml %W/V:.5 arlo Trigona A.A. 007-
Exprimntal St-up (I) arlo Trigona A.A. 007- Exprimntal St-up (I) arlo Trigona A.A. 007-
Exprimntal St-up (I): circuit arlo Trigona A.A. 007- Rsults Dtction of magntic particls RTD variation, function of distanc and numbr of particls arlo Trigona A.A. 007-
Rsults DRTD=7.143 µs ~800 particls ~53*53 particls 809 particls 1 particl M10-10 ~ 1 µm 1 µm * 53= 0.053 mm Surfac ara 1/0 mm arlo Trigona A.A. 007- Exprimntal St-up (II) Magntic particls for DNA squncing N S NS 1µl 1µl spot arlo Trigona A.A. 007-
Exprimntal St-up (II) Glass support for fluxgat coils arlo Trigona A.A. 007- Rsults Th xprimnt has bn conducd by taking svral obsrvations of th fluxgat output for various spot sizs (obtaind via th dposition ion of diffrnt known fluid volums ranging from 0.5µl l to 4µl). 4 Each spot is maintaind in th masuring position for 300 sconds. arlo Trigona A.A. 007-
Rsults RTD variation obtaind via th dposition of diffrnt known fluid volums ranging from 0µl 0 l to 4µl. 4 arlo Trigona A.A. 007- Exprimntal St-up (III) Systm for volcano particls dtction Magntic particls arlo Trigona A.A. 007-
Exprimntal St-up (III) Primary: 1000 coils 100 µm Scondary: 1000 coils 100 µm 100 µm cor arlo Trigona A.A. 007- Volcano particls Rsults With magntic particls Without magntic particls arlo Trigona A.A. 007-
Exprimntal St-up (IV) Th xprimntal st-up consists of a RTD-Fluxgat magntomtr, opratd with a sinusoidal bias signal @80Hz and 0 mapp of amplitud, a prmannt magnt is usd to polariz Etna volcanic ash (0.5 mm of diamtr-yar of ruption 001) containd in a plastic tub. Volcanic ash Fluxgat Prmannt Magnt arlo Trigona A.A. 007- Rsults Th xprimnt has bn conducd by obsrving th Fluxgat output t signal for diffrnt valus of volcanic particl numbrs. arlo Trigona A.A. 007-
Rsults Th nxt figur shows th volution of th Rsidnc Tims Diffrnc for diffrnt volcanic ash quantitis (from 0 ml to 3.5 ml) and th RTD variation. Variation of RTD as function of volcano particls quantitis Evolution of th Rsidnc Tims Diffrnc incrasing th volcanic ash quantitis. arlo Trigona A.A. 007- onclusions RT-Fluxgat Principl Exprssions of RTD and Snsitivity Fluxgat for biomdical applications St-up with PB FR4 St-up with Wir cor Fluxgat for volcanic ash dtction St-up with PB FR4 St-up with Wir cor arlo Trigona A.A. 007-