Лекции ЭЦМ часть1
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111
. 5.13. : — -
; — -
m .
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m,
9 .
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T 10 %, I0 — 10 .
5.14,
I0. VT1 VT2
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. 5.14.
VT1 VT2
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R4 .
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0,3% .
( . 5.13, ) -
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U = -I R = - I0R exp(U / T).
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. 5.15.
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. 5.15. I0
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I 1=U /R1; I 2 = U /R2; |
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U1 = U R4/(R3 + R4). |
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I 0 , .
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.
113
I2=U1/R1. ,
R2. ,
, ( . 8).
. 8.
KU ,
U . -
. 8 :
I1 = I2 = (U1–U )/R1,
U = –(U /KU),
U2= U – U .
:
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R = – ( U2/ I2) = KUR1.
. -
. 8 .
. -
(
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. -
.
114
, . 9, ,
R1.
, R1 -
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. 9. , ,
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n- :
(U – Un)/R2 – Un/R3 = 0,
(U1 – Up)/R2 + (U2 – Up)/R2 = 0,
(U – U2)/R1 – (U2 – Up)/R2 – I2 = 0. /p>
, Un=Up, :
U2, -
– R3 =(R2)2/(R1 + R2).
:
I2= U1/ (R1||R2).
R3,
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U1 (8) ( -
, ). ,
. -, R , , , , .
115
, . 10. -
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U4 = – U3 = U1 + (R2/R3) U2 .
.
. 10.
(U4 – U2)/R1 – U2/R3 – I2 = 0.
U4, :
I2 =U1/R>1 + U2[( R2 – R3 – R1)/R1R3],
, ,
R3 =R2 – R1.
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( -
). ( -
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, (8).
– -
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116
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, -
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( . 11 ).
. 11.
, R1 U1.
, ).
R1 U1/R1. -
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I2 =(U1/R1 )[1 –(1/B)]. |
(9) |
B. -
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I2 =(U1/R1).
. 11
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I2 = – (U1/R1)[(1 – (1/B)],
117
. .
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. 11 , -
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1. .
: I =(U -U )/R2 . -
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h21 U
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2. .
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3. .
4. .
: I =0.66/R2 ; 3 VT2 -
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119
5. .
6. .
R =R , I =I h21 /(h21 +2) -
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( - 25% -
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7. .
I =const , . I 2 , I 1 . -
: R =h21 R ,
1/h21 ^2. -
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8. .
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9. .
VT3 (
VT2) VT4.
10. .
VT1, VT3, VT4...VTn. - -
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