6.
6.1.
6.2.
6.3.
6.4.
6.5.
6.6.
(sensor) , . (transducer) .
(, , , , ). , . () / .
. , . , , .
, . , .
. 2.1 .
, , (, , . .), , .
, , .
, , . , . , .
2.1
/ | |||
/ | |||
. 2.1.
(. 2.1).
(). () - (). () -
|
|
, . , . , ( ) .
, (smartsensor), , . , . (AnalogDevices, TexasInstruments, Philips .) ( ) , , , flash-, .
. . 2.2 .
2.2
120 , 350 , 3500 | |
3503500 | |
3503500 | |
100 10 M | |
1001000 | |
100 10 M |
, , , .
. 2.2.
Vout = I R (R +∆)
. 2.2.
, , , . .
, , (. 2.3).
R 1 − R 2
Vout = R R 1 R +1 4 V − R R 2 R +2 3 V = 1+ R R R R 1 41+3 R R 3 2 V
4
V 0 = 0, R R R 1 4 = R 3 2
. 2.3.
(R 1/ R 4 = R 2/ R 3), ().
R 1 , R 2/ R 3 = K, R 4, (, ), / R 1. , , .
|
|
(. 2.4). , , ( V = 10 ).
() (). , 10 , 10 , 1 /.
V ∆ R 4 R + ∆ R | V ∆ R 2 R + ∆ R | V ∆ R 2 R | V ∆ R R |
2 2
. 2.4. ( )
, . , (. 2.5), .
, . 2.6. (). RF (). . .
I R ∆ R ∆ R I 2 ∆ R I 2 ∆ R I ∆ R
4 R + 4
. 2.5. ( )
Vout = V 4 R +∆ R ∆ R
2
. 2.6.
Vout = − V ∆2 R R
. 2.7.
, . 2.7. . , , (∆ R). .
().
, . , . . (, ). , . . 2.3 .
2.3
, | |
() | |
, | |
|
|
( ), .
, - (. 2.8). , ( , L, ρ), , :
R =ρ L,
A
∆ R = GF ∆ L,
R L
GF ( 2.04.5 , 150 ).
, , ∆ L/L, (. . .). , , , , .
. 2.8.
, .
(. 2.9).
. 2.9.
, (, , . .). , .
2.4
0.140,000 ε | 0.0013000 ε | |
2.04.5 | 50200 | |
, | 120, 350, 600,..., 5000 | 10005000 |
0. 1 %0.2 % | 12 % | |
, | 0.4150 ( 36) | 15 |
(), . , () . , .
(, ), , . (. 2.4).
(. 2.10). , .
, , . 350 , . , (. 2.11).
|
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. 2.10.
. 2.11.
10 3 / 30 .
, . (, ) .