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176

CAPITOLO 6

Ampli!catori

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6.3.2 Proprietà dei circuiti reazionati ideali

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rimento è

A s

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F(s

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X

e genera

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S

f

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YDORUH GHOOD JUDQGH]]D G¶LQJUHVVR

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in

attraverso

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d’errore

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A s

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A s

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F s

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S

u

S

in

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FRQR DOOH VHJXHQWL UHOD]LRQL

İ

=

S

in

+

S

f

=

S

in

+

S

u

·

F s

S

u

=

İ

·

A s

[

S

in

+

S

u

·

F s

]

·

A s

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1

1

1

1

1 1

G s

S

S

A s

A s F s

A s

G F s

G

( )

( )

( ) ( )

( )

( )

u

in

loop

loop

= =

− ⋅

=

= − ⋅

Eq. 6.6

4XHVWH HVSUHVVLRQL YDOJRQR TXDQGR LO

guadagno di anello

G

loop

=

A s

·

F s

ULVXOWD HVVHUH

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1

1

S

A s F s

S

G s

( ) ( )

( )

in

in

loop

ε

=

− ⋅

=

Eq. 6.7

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ε

= ⋅

=

1

S

A s F s

S G s

G s

( ) ( )

( )

( )

f

in loop

loop

Eq. 6.8