Tgp Chi Khoa Hpe Gido Due Ky Thugt (32/2015) Trudng Dgi Hpe SuPhgm Ky Thuat TR Hd ChiMinh
ITNG DVNG MEMRISTOR DE THIET KE MACH NHAN DANG KI Tif StT DyNG BO NHAN TIN HIEU
MEMRISTOR-BASED CHARACTER RECOGNITION USING SIGNAL MULTIPLICATOR
Huynh Ho^ng Ha, V6 Minh Huan Trudng Dgi hoc Suphgm Ky Thugt TP.HCM
Ngay toa scan nh$n bai 02/02/2015. ngay phan bi§n danh gi^ 8/3/2015. ngay chap nh$n dang 12/3/2015
TOM TAT
Thiit ki mgch nhdn dgng ki tu ung dung memristor thong qua phep nhdn tin hiiu dugc trinh bay trong bdi bdo. Mgch nhgn dgng su dung 7 congXOR dugc thiit ke tic memristor. Bdng each diiu khiin hogt dong cua memristor phu hop, ta se thu dugc dien dp ngd ra tuong ung vdi timg tap du lieu ngo vdo. Dua vdo dien dp ngo ra va tap mdu du lieu co san, ta xdc dinh dugc ki tu cdn nhgn dgng. Ddc biet, ngo ra dugc luu tr& trong cac phan hi memristor, khong bi mdt dir lieu ngay cd khi ngung cdp nguon va du" lieu ngo ra cd the truy cap lai dugc sau do. Cdu trite mgch nhgn dgng ki tu co ung diing memristor giup tiit kiem dugc ndng lugng tieu hao, qud trinh xu ly nhanh vd mat do tich hgp cao khi so ngo vdo cdng l&n. Bai bao sii dung md hinh memristor ly tudng. Tdt ca kdt qua nghiSn curu dugc md phdng bang cong cu Cadence.
Tir khda : memristor, congXOR, phep nhdn tin hieu, nhgn dgng ki tu.
ABSTRACT
A character recognition based on memristor via resistive logic signal multiplication is introduced. The integrated circuit uses seven memristor-based XOR gates and XOR gate is made by the combination of Memristors. By controlling the memristor's operation suitably, we obtain the corresponding output voltage according to the inputs. The interests of this circuit structure is the output registered in the nonvolatile memristors, so that the computed output can be stored without power supply and accessed anytime later This circuit structure saves energy, the processing speed is fast and the integration density is high for the large number of inputs. The report mainly focuses on the model of ideal memristor All the simula- tion results are studied using Cadence tool.
Index Terms: memristor, XOR, signal multiplication, character recognition.
L G l 6 l THIEU
Viec xu ly thdng tin ngay cang phirc tap ddi thiet bi memristor[l], [2] hoat ddng nhu cac hdi cac he thdng trong tuong lai phai cd do tich chuyen mach, cd kha nang dieu khien dugc hgp cao hon, de vugt qua dugc gidi ban hien bang dien ap ludng cue, da dugc sir dyng de tai cua cdng nghe CMOS truyen thdng, cimg xay dung len cac mach ban dan mat dd cao.
vdi gidi han ciia phuong phap "quang khde". Ngoai ra, memristor cdn cd mot dac tinh quan Dinh luat Moore's Law cung dang ddn tiSn trong nua la kha nang luu trii trang thai h d ddn gidi han cua mmh vi kha nang tich hgp khang trudc do, ngay ca khi ngung cdp ngudn cua cdng nghe CMOS la cd gidi han. Dd dat cho mach. Md ra kha nang ap dung cac thilt bj dugc yeu cdu vd do tich hgp ngay cang cao, memristor nay vao cac bp nhd khdng bay hoi, thi cac cong nghe, chdt lieu mdi cung da va cdng logic, FPGA vdi mat dp cao hon, quan dang dugc nghien ciiu nhigu vdi muc dich la trpng hon la cd kha nang thich nghi vdi cdng thay thd duoc cdng nghe CMOS hien nay. Cac nghe CMOS [3], [4]. Do dd, cac kien triic tinh
Tgp Chi Khoa Hpe Gido Dge Ky Thugt (32/2015) Trudng Dgi Hpe Su Phgm Ky Thugt TR Hd ChiMinh
toan nano dua tren memristors hiia hen se tao ra dugc cac ling dung tinh toan m$t dp cao va tieu thu cdng sudt thdp.
Cd rdt nhidu co hdi nghien ciru dugc md ra cho cdng nghe memristive (trd khang nhd).
Vi du nhu eac ung dyng; bp nhd khdng bay hoi tich hgp mat dp cao, bd xir Iy tin hieu [5], synaptic neuromorphic networks [6]... Dua vao cac bai bdo da nghien ciiu, bdi bdo ndy se gi&i thieu vi mgt kiin tnie tinh todn trd khdng nhd mat do cao de nhgn dgng cdc ki tu thong qua muc dien dp ngo ra tinh toan dugc, dua tren nguyen ly cua bp nhan tin hieu co ban.
Trong nghien ciiu nay, thi bd nhan trd khang nhd se duge nhiing vao trong mach tieh hgp lai, gdm cd cac phan tir memristor 2 trang thai va chuyen mach CMOS. Mach nh^n dang ndy se difa tren nhieu cong logic XOR, dong vai tro nhw bp nhan trd khang, dugc kit noi v&i nhau. Cu the Id, mot day song song cdc cong XOR dugc ket hgp vdi nhau di tinh todn cdc phep nhdn mdt each ddng thdi va dugc tdng hgp kdt qua d ngo ra ciia mach.
Bai bao nay dugc trinh bay nhu sau. Phan I gidi thieu tdng quan ve bai bao. Phan II se trinh bay ve dac tinh cua memristor. Phan III trinh bay nguyen ly hoat dgng cua cdng log- ic XOR sir dyng memristor. Phdn IV la thiet kd mach nhan dang ki tu su dung memristor.
Phan V md phong mach bang cdng cu Ca- dence. Theo sau do, phan VI se ket luan de tdi.
II. TINH C H A T CUA MEMRISTOR Memristor dugc phat hien bdi Leon Chua vao nam 1970, ddng vai trd nhu nguyen td
mach CO ban cdn thiSu, ben canh dien trd, cugn day va tu dien. Memristor the hien mdi quan he giiia didn tich va tu thdng nhu hinh 1 [8]. Nhung den nam 2008, mdt nhdm nghien Cliu ciia R.Stanley Williams d phdng nghien Cliu HP mdi cdng bd su tdn tai ciia nguyen td mach nay. Nguyen lieu chinh su dung xay dung memristor la mpt lop titan oxit mdng.
Khdng gidng nhu eac nguyen td co ban khac, memristor cd the thay ddi dugc tr^ng thai trd khang. Ngay ca khi ngimg cung cap ngudn thi memristor van ghi nhd dugc lugng dien tich da ehay qua. Neu su dung mdt ngudn dien ap nhd de dieu khien, thi chiing ho^t ddng nhu cac thiet bi m^ch tuong tu; nguge lai, neu sir dung ngudn dien ap Idn, thi chiing hoat ddng nhu cac thiet bi sd vdi 2 miic trgng thai trd khang va dugc dieu khien bang 2 miic dien ap ludng cue [8], [9], cd dac tuyen 1-V nhu hinh 2(b).
Hinh 1: Md ta mdi quan he giiia dien tich, ddng di$n, dien ap, tir thdng
(a)
Hinh 2: (a) Memristor; (b) Dac tuyen I-V cua memristor khi sii dung dien ap Idn
Tgp Chi Khoa Hpc Gido Dgc Ky Thudt (32/2015) Trudng Dgi Hpe Su Phgm Ky Thugt TR Hd Chi Minh
Bai bao nay chi tap trung phan tich vao khia canh hoat dgng nhu mdt thiet bi sd cua memristor. Nen dac tuyen I-V trong trudng hgp nay gidng nhu hinh 2(b). Hinh nay the hien mdi quan he giiia ddng dien va dien ap, thdng qua dd cho thdy tinh chat trd khang ciia memristor. Trd khang se dugc giii khdng ddi khi didn ap dat vao (V^^^^) khdng vugt ra ngoai nguong [VQP^^, V^^^og^] va dao trang thai trd khang khi sir dung dien ap ngoai nguong \y^
V 1
PEN' 'CLOSE-I"
Khi dd, memristor dugc xem nhu mdt thiet hi trd khang nhd luong cue, gdm cd 2 trang thai h d khang. Trd khang d miic thap dugc ki hieu RQJ^, h d khang d miic eao dugc ki hieu la RQPP [10]. Trd khang gia dinh se chuyen hang thai hi R^^^p sang R^^ (hay R^^^ sang R^^^) vdi khoang thdi gian chuyen mach Tg = 0 khi dat vao 2 dau memristor mot mirc dien ap V^^.^
(hay V^.^) vdi bien dp Idn hon (hay nhd hon) mire dien ap ngudng V^^^g^ (hay V^p^^). Ddng thdi, qua hinh nay can phai thuc hien hong mdt khoang thdi gian T^j^^p phu hgp [11], [12]. Md hinh dac tinh ciia memristor dugc md ta bang ngdn ngii Verilog-A. Cac thdng sd thiet hi dugc sii dung trong phan sau cua bai bao nay: R^^p - 5 kH, R „ , = 1 kH, V,^^^^ - 3-5 V, V , p , , - -3.5 V, 1 - 0, T „ , , , - 10 us, R3
= 1 k n , Vgp^ = 5 V, Vj,g.p = -5 V. Vdi qui udc:
miic logic ' 1 ' nghTa la: V^= V^^^, R ^ - R^^,
and Rp= R^^. Miic logic ' 0 ' nghTa la: V ^ ^ 0, R , = RoPP,andR,-R^Pp.
III. NGUYfeN LY H O A T BQ^G CUA C O N G X O R Sty DUNG M E M R I S T O R
Cau tnie mach XOR sir dyng 2 memristor, 3 ehuydn mach CMOS va 1 dien trd [13]. Vi kha nang tich hgp cao ciia nguyen td memris- tor nen cau tnie mach cd m^t dp tich hgp cao hon cdng nghe CMOS truyen thdng. Cau tnie mach chi tiet dugc trinh bay trong hinh 3(a), vdi 2 ngo vao: ngo vao di^n ap Vj^ (x) va ngo vao memristor R^ (y), 1 ngo ra la memristor Rp (p'). Khac vdi cdng XOR truyen thdng, qua trinh xii ly cua mach thyc thi qua 2 budc nhu trong hinh 3(b). Va bang su that tuong img giua 2 ngo vao vdi 1 ngo ra dugc trinh bay nhu trong hinh 3(c). Ngo ra d budc 1 la p, ngd ra 0 budc 2 la p ' , day la ket qua cudi cimg cua ngd ra. De mach hogt dgng hieu qua, thi gia tri cua Vp, V^ phai dugc lua chpn phu hgp va thda man 4 rang budc [7] ( vdi a = K^^J R „ , a n d p = R „ / R 3 ) :
KjEr < 2 X VciosE (1)
I ' s n . X l + W x l ' ^ i - C a + fflxVnoK (3)
Vx Rp
-ffi
(a)
Ys ISx
Rs:
- u - t sT
(b)
Step-I Step-II
Vp
VRST
VsET Si S2
1 0 0 I ( c ) X y
0 0 0 1 1 0 1 1
P P 0 fo\
0 1 1 ; 0 i l : 0 1,0,'
Mode p'=y p'=y
Hinh 3: (a) Mach cdng XOR sir dung memristor, (b) Qua hinh xu ly, (c) Bang su that ciia cdng XOR
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Trudc khi qua trinh xii ly xay ra 2 budc, 2 ngo vao dugc gan gia tri trudc. Sau dd, trong budc
^' ^p " '^Rsp S, - ' 1 ' , S, - '0', nen Rp dugc ndi tat xudng ddt, va vdi miie dien ap V^.j. d chan Vp dugc dat hoan toan len Rp, lam cho trd khang eiia memristor Rp dugc dua ve miic '0' (R(jFp), bat chap ngd vao x, y dang d trang thai nao.
Trong budc 2, Vp = V^^ S, = '0', S, - ' 1'.
Khi X = '0', thi S^ khdng ddn, Rp va R^, dugc mac ndi tiep va ndi xudng dat thong qua S, nhu hinh 4(a), V^^^V^X R/(R^-i-R^.muy
= '0', till V^ = 2.5 V, h-d khang Rp khdng ddi, nen p' = 'C. N^u y - ' 1', thi V^ - 4.16 V, trd khang Rp dao trang thai, nen p' = ' 1'.
Giai
Nguge lai, khi x = ' 1', hay V^ .(>0), thi Sj^ din, Rp va Ry se duac mac song song va noi tiep vod R^ nhu hinh 4(b).
Neu y = '0' thi ta co he phuong trinh (5):
(il + i2-h = 0 I 5ii + 13 = 5
(5)
Giai phuong trinh 5 thu dugc: ij = 0.77 mA;
i,-0.37mA;i3= 1.14 mA.
Vjy. = i, X Rp = 3.85 V. Nen Rp se chuyin trang thai tii 'O'sang ' 1 ' , hay p ' ^ ' 1 ' . Tuong tu, neu y = ' 1' thi ta cd he phucmg trinh (6):
il + 12 - ia = 0 Sil - iz = 2
Sil + 13 = 5 (6)
he 6 thu dugc: i, 0.64 mA;
i, = 1.18 mA; i^ = 1.82 mA. Nen V^ ^ i, X Rp = 3.2 V. Nen Rp se giii nguyen trang thai '0' hay p' ^ '0'.
Vp=VsET Vp=VsET V X = V E V L
V R Y
Hmh 4: Mach hmh 3 dugc ve lai: (a) Budc 2 vdi Vx = 0; (b) Budc 2 vdi Vx = V^^ > 0
rV. THIET KE M^CH NHAN DANG KI TU" SU" D VNG MEMRISTOR Trong nhieu ling dung nhan dang mau cua am thanh, ki tu, hinh anh, hay trong nhieu phan tich dii Ueu khoa hpc ciia khi hau, khdng gian, y hpe..., phep nhan giua mau du lieu ngo vao va dii lieu tham chieu dugc luu tru trudc la mdt phucmg phap nham xac dinh su ddng dang ca ban de nhan dang cac mau dii lieu ngo vao.
Cdng XOR xay dung hi memristor dugc sii dung nhu la mdt phan tir nhan, dimg de thiet ke mach nhan dang ki ty. Mdt trong hai ngo vao ciia cdng XOR dugc dimg de luu trii du lieu tham chidu (R^), ngo vao cdn lai (Vj^) dung lam ngo vao cua mach. L phan hi nhan XOR dugc su dyng de xay dung mach nhan dang ki tu nhu hinh 5. Ngd ra ciia mach la dien ap VjjY dat hen dien trd R^. Ngoai ra, mach cd them mdt ngd vao dieu khien ap Vp Vi vay, ndu dimg L cdng XOR, thi mach se gdm L+1 ngo vao va mdt ngo ra nhu hinh 5(b).
Tgp Chi Khoa Hoc Gido Bgc Ky Thugt (32/2015) Trucmg Bgi Hoc SuPhgm Ky Thudt TR Hd ChiMinh
3 ^ ^ ^ — ' -
•
(a) (b)
Hinh 5: Mach nh$n d?ng ki tu sir dyng bd nhan: (a) Vdi cdng XOR thdng thudng;
(b) Vdi cdng XOR su dyng memristor Hinh 5(a) la mpt dang mach nhan dang, sir
dung cac phdn hi nhan XOR theo cdng nghe CMOS truyen thdng. Ngd ra cua cac cdng XOR nay la di€n ap, mang 2 muc logic '0' va ' 1 ' , khdng the ket hgp trye tiep vdi nhau, vi v|iy phai su dyng them mpt bd cdng ngo ra.
Sd ngo vao cua mach cang Idn, thi cau tnie bd epng cang phiic t^p, thdi gian xii ly eang lau.
Trong khi do, hinh 5.1(b) la mach nhan dang sir dyng eae phan tii nhan XOR ed chiia mem-
ristor. Ngd ra cua cac cdng XOR nay la trd khang Rp^, nen cd the ket hgp vdi nhau, tdng trd cua cac ngo ra cua cac cdng XOR dugc tinh thdng qua didn ap Vp ma khdng can diing thdm bd cpng. Vdi kien tnie mach nay, thi tdc dp xii ly hoan toan khdng phy thupe vao sd lugng ngd v^o, vi^c them, bdt ngo vao ciing khdng gay anh hudng den toan mach. Cau tnie chi tidt cua mdt cdng XOR dua tren memris- tor dugc sir dyng trong m^ch nhan dang nhu hinh 6.
Xi \
"p -
mW\
pyy ^-.
Hinh 6: Cau trie cong XOR su dung memristor
C4u trie c6ng XOR trong hinh 6 tuong tu qua 3 budc, va co them 2 chuy6n mjch Sj va nhu cdng XOR trong hinh 3, dugc thuc thi S^, dimg da tinh dien ap ng6 ra cua m^ich o
buoc III nhu trong bang 1.
Tgp Chi Khoa Hge Gido Bgc Ky Thugt (32/2015) Truimg Bgi Hge Su Phgm Ky Thudt TR Hd Chi Mmh
Bang 1: Trinh tu thg:c thi ciia mach n h ^ dang Id tu Budc
I 11
m
Vp
V V
SET
V
EVL
S, 1 0 0
Sa 0 1 0
s,
1 1 0
SB 0 0 1
Ch^dv Reset XOR Evaluate
Ngd vao R^j (y,) cua cac cdng XOR ddng vai trd luu trii dii lieu tham chieu, va dugc dat ed dinh la R^p^CO'). Cac ngo vao V^^^ (x^) la cac ngo vao ciia mgch. Qua trinh xir ly ciia mach n h ^ dang dien ra theo 3 budc nhu bang 1. Trong budc I va II, cac phan hi XOR thyc hien phep nhan mdt bit nhu cdng XOR trong hinh 3, de tinh toan trd khang ciia Rp^. Vdi ngo vao R^i deu dugc cd dinh la R^^^p, nen khi ngo vao Vj^j cd gia tri logic la ' 1 ' , thi Rp^ se dao hang thai len ' T (R^j^); nguge lai, khi V^^^ cd gia tri logic la '0', thi Rp, giu nguyen trang thai '0' (Rppp). O budc III, cac chuyen mach S,, S^, Sj deu ngung dan, S^ dan. Cac memristor Rp^
dugc each Iy vdi mach va ket ndi song song vdi nhau nhu hinh 7.
mm
-FTnm
¥ms
Hinh 7: Mach hinh 5(b) dugc ve lai d budc III Theo hinh 7 ta cd:
Rp Rpo Kpi " P i - i _ VpXRo _ VEVI,XRP
VxY = Rp+Rp Rp+Ro
(7) (8)
0 buac iil, Vp va Rp phai thoa man rang bupc sau:
V <(V -V ) < V (9)
OPEN V EVL XY' CLOSE '• '
K6t hop (8) va (9) ta dugc:
''OPEN ^ „ , „ ^ 'CLOSE (10) Vay khi Vp va R^ dugc lya chpn phu hgp vdi rang budc (10), ta se tinh dugc dien ap ngo ra VjfY (theo edng thiic (8)). Gia hi dien ap VjjY thay ddi theo ngd vao Vj^^ cua mach. Vdi so dd mach nay, ta cd the nhan dang dugc bat ki mdu ki ty nao, bang each quy udc mdi ki ty mudn nhan dang ling vdi mdt trudng hgp ngd vao. Va dya vao dien ap V^^^ do dugc d ngo ra, ta xac djnh dugc ki ty can dugc nhan dang.
V. MO PHONG: MACH NH^N DANG KI TU" BANG CONG CV CADENCE
Dd tai da dugc md phdng bang cdng cy Ca- dence, cdng cy chuyen sir dyng hong ITnh vyc thidt kd chdt ban ddn, vdi 7 cdng XOR (L=7), Rp = 1 kn, Vgyj^ sir dyng 2 miic dien ap 5 V va -5 V tuong ling vdi 2 miic logic ' 1 ' va '0' (trong budc III). Cac ngo vao R^^ da dugc d^t cd dinh miic '0'. Vl vay, mach cd 8 ngo vao va 1 ngd ra nhu hinh 8(a). Cau tnie ciia mdt cdng XOR hong Cadence dugc thi^t k6 nhu hinh 8(b). Trong md phdng nay, myc tieu la nhan dang cac ki ty hong tir "MEMRISTOR", nen d8 tai da ti§n hanh ma hda tuong img 16 ki ty chu vidt tir 'E' d§n 'T' trong bang chu cai. Bd 16 trudng hgp ngd vao cung vdi 16 miic dien ap ngo ra se tuong ling vdi 16 ki ty nhu hong bang 2.
Tgp Chi Khoa Hge Gido Bgc Ky Thudt (32/2015) Trudng Bgi Hge Su Phgm Ky Thugt TR Hd ChiMinh
(a) (b)
Hinh 8: (a) So dd mach nhan dang ki ty trong Cadence; (b) Cau tnie I cdng XOR Bang 2: 16 ki ty 'E' den 'T' tuong ling 16 trudng hgp ngo vao va ngd ra (theo tinh toan)
CHARACTER E F G H 1 J K L M N 0 P Q R S T
Vp 0 0 0 0 0 0 0 0
Vx.
0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 I
Vx, 0 0 0 0 0 0 1 1 0 0 0 0 0 0 1 I
Vx, 0 0 0 0 0 1 1 1 0 0 0 0 0 1 1 1
Vx3 0 0 0 0 I I I 1 0 0 0 0 1 1 1 1
v„
0 0 0
0 0 0
V V
X5 X6
0 0 0 1 1 1 1 1 I 1 1 1 1 1 1 1 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1
V x v W -2.917 -3.438 -3.750 -3.958 -4.107 -4.219 -4.306 -4.375 2.917 3.438 3.750 3.958 4.107 4.219 4.306 4.375
Tgp Chi Khoa Hge Gido Bgc Ky Thudt (32/2015) Truing Bgi Hge Sir Phgm Ky Thudt TR Hd ChiMinh
So do mach dugc thi^t k^ nhu trong hinh 8 bang cong cu Cadence. Qua trinh thuc thi diln ra theo 3 buoc theo bang 1. Va vdi 16 lei tu chij da dugc ma hoa truoe nhu bang 2, de tai da tidn hanh nhan di$n 7 Iti tu: E, 1, M, O, R,
S, T trong tir "MEMRISTOR". Kgt qua dang song tra v6 chinh la dien ap ngo ra V ^ nhu trong hinh 9. Va dien ap do dugc (o buoc 111) tuong ung voi cac trudng hgp ngo vao dugc tong hgp trong bang 3.
__^_^ •
I I I I I I I M I I I I I I ~
I I ' , j I I I ^ I I I I I I I I i ~
Hinh 9: Dang song ngo ra cua mach nhan dang lei tu Bang 3: Dien ap ngo ra do dugc g buac 111 tuong img vdi cac ngo vao Kitv
Vxy do dugc (V) Vxy tinh toan (V) DO chinh xac (%)
M 2.917 2.917 100
E -2.917 -2.917 100
M 2.917 2.917 100
R 4.2 4.219 99
I -4.1 -4.107 99
S 4.3 4.306 99
T 4.4 4.375 99
O 3.75 3.75 100
R 4.2 4.219 99 Trong hinh 9, mdi bd ngo vao dugc thyc
thi qua mdt qua trinh hong 30 us gdm 3 budc, mdi budc thyc hien hong 10 us. Trong budc I va II, Sp = '0', ngd ra V^^y hi each ly, ndi xudng dat thdng qua dien trd R^ , nen V^^ = 0 V. 6 budc III, Sp = ' 1', dien ap ngd ra (V,^) cd gia tri va dugc diing de nhan d^ng ki tu trong mdi qua trinh (kdt qua do ludng cy the nhu bang 3). Cudi ciing, tra dien ap ngo ra V^^
do ludng dugc d bang 3 vdi kdt qua tinh toan theo ly thuydt d bang 2, ta xac dinh dugc ki hr cdn dugc nhan dang.
VI. KET LUi^N
Bai bao nghien ciiu tap trung vd cdu hiic, dac diem cua cdng ngh6 vi mach mdi - dien trd nhd (Memristor). Qua dd, ling dyng mem- ristor dl thiSt k6 mach nh|n d^g ki ty. Trong
dieu kien ly tudng, bd qua dien ap tieu hao ciia mach, thi ket qua nhan dang chinh xac den 99%. Nhung mach lai cd han che, dd la miic dp phi tuyen ciia ket qua Idn, vdi miic ngudng thap nhat giiia 2 gia tri ngo ra lien tiep ciia mach la 0.071(V). Tuy nhien, miic ngudng thap nay cd the khac phye dugc, bang each tang sd lugng ngo vao, lua chpn lai gia tri Vp va Rp phii hgp.
Vdi viec sii dung memristor, kich thudc mach nhd hon, sd lugng phan tii mach it hon, va nang lugng tieu hao thap hon vi cac phan tir memristor cd kha nang tich hgp cao, va duy tri dugc hang thai ngay ca khi ngung cap ngudn.
Tuy nhien, day la ITnh vyc kha mdi, tham chi mdi cd mdt vai cdng trinh nghien ciiu thye te va chi dugc nghien ciiu hong phdng thi
Tgp Chi Khoa Hge Gido Bgc Ky Thugt (32/2015) Trudng Bgi Hoc SuPhgm Ky Thugt TR Hd ChiMinh
nghiem la chinh. Nen day la mgt thach thtxc trien tiep theo se tap trung vao t6c do chuyen Idia Ion, d6ng thoi ciing chila nhiSu tiSm nang mach cua memristor, ling dung cdiig nghe moi dl phat tridn cong nghe vi mach hien nay. nay vao cac mjch 16 hgp truyen th6ng, va thiet Sau Idii hoan thanh ii tai nay, hudng phat kl cac bg nho vai do tich hgp cao hon.
TAI LIEU THAM KHAO
[I] L. O. Chua and S. M. Kang, "Memristive devices andsystems", Proc. IEEE, vol. 64, pp.
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