y*m
发帖数: 144 | 1 let opampA(s) be in a unit feedback config, the transfer function is A(s)/(1
+A(s)).
What is the transfer function if putting the impedence Z(s) between opamp
inverting input port and the opamp output? | l*****i
发帖数: 296 | 2 depends on the input impedance of opamp.
suppose the input impedance is Zin
then
A(s)(vin-Zin/(Zin+Z(s))vout)=vout
H(s)=A(s)/(1+Zin*A(s)/(Zin+Z(s)))
(1
【在 y*m 的大作中提到】
: let opampA(s) be in a unit feedback config, the transfer function is A(s)/(1
: +A(s)).
: What is the transfer function if putting the impedence Z(s) between opamp
: inverting input port and the opamp output?
| y*m
发帖数: 144 | 3 if we consider Zin as mentioned, it simply gives a feedback factor beta= Zin
/(Zin+Z(s)), then the transfer function is H(s)=A(s)/(1+beta*A(s)).
for unit feedback, beta=1,H(s)=1 given A(s) is large within the frequency of
interested.
What is the transfer function if only Z(s) here?
【在 l*****i 的大作中提到】
: depends on the input impedance of opamp.
: suppose the input impedance is Zin
: then
: A(s)(vin-Zin/(Zin+Z(s))vout)=vout
: H(s)=A(s)/(1+Zin*A(s)/(Zin+Z(s)))
:
: (1
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