tổng quan về tương tự số

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môc lôc
I. Tæng quan vÒ biÕn ®æi t¬ng tù-sè (ADC) 3
I. Tæng quan vÒ biÕn ®æi t¬ng tù-sè (ADC) 3
II. C¸c ph¬ng ph¸p biÕn ®æi t¬ng tù – sè (ADC) 5
II. C¸c ph¬ng ph¸p biÕn ®æi t¬ng tù – sè (ADC) 5
  
!"#"$%&'()*+,*-./'01
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
 !"#$%
&'#()*%
+ #,-./)0%
III. Sai sè trong biÕn ®æi t¬ng tù – sè (ADC) 15
III. Sai sè trong biÕn ®æi t¬ng tù – sè (ADC) 15
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Më ®Çu
Trong ba thập kỷ qua, kỹ thuật xử lý thông tin đã phát triển mạnh. Hệ thống
truyền tin được tổ chức theo các lớp chức năng: định dạng và mã hoá nguồn tin, điều
chế, mã hoá kênh, ghép kênh và đa truy nhập, trải phổ tần số, mật mã hoá và đồng
bộ. ?@&,A"'B,A@"'CDE#F'G
,: G/#HB,A,)I J@@K$ 
L'&=MM' .JNA@"#OJ"&

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J A"@'#JR#D+ S$
T@'CDE>@''CJM'UH@+ 
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+ W&/&>@'HDAH$XB"-G&'Y
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&&  #+S$
Bài viết này sẽ trình bày lý thuyết tổng quan và phân tích các kĩ thuật biến đổi
đồng thời đánh giá sai số trong biến đổi tương tự - số ADC.
I. Tæng quan vÒ biÕn ®æi t¬ng tù-sè (ADC)
\H["@# RFHS"
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H×nh 1. S¬ ®å khèi bé biÕn ®æi t¬ng tù - sè ADC
Nguyªn t¾c:
V>@'HU&,:,AI,E'>@'&,AI,E'U&
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B¶ng 1: Sù biÕn ®æi tr¹ng th¸i trong bé biÕn ®æi A/D song song
tuú thuéc vµo ®iÖn ¸p lèi vµo.
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M'Q&U*FiW*'.i:$%H.&'#CW&O
(&:IFW&R.+SQ&,E'$XB,pF"Q&,d

>  ,PN"IKDP: .=,p
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&I$
2.2. Ph¬ng ph¸p song song c¶i biÕn
XB,AQ&  %"U: =
+ ,,}#N:DQ&1$tA"#N:nM322:
 $B,.B',p":$b'"#0[
W&U  #N!"$
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Q&@# $W,::q&),:@&& d$
X@# U+,1@$5MD`A)UB'DODNA"
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W&O#.KDP@)UG.JRW
,::N[>,E'S .0U :"$
H×nh 4: Bé biÕn ®æi A/D thùc hiÖn theo ph¬ng ph¸p song song c¶i biÕn.
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3.3. Ph¬ng ph¸p träng sè
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H×nh 5: Bé biÕn ®æi A/D lµm viÖc theo ph¬ng ph¸p träng sè
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6

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