Operational Amplifier Circuits

Offset

Errors

43

R

f2

1-1

c

o

7fr

itr

Figure

3-3.

Two-stage operational amplifier circuit with blocking capacitor

C.

1.

The

offset, even within

a

single stage, must not

be so

great that satura-

tion

can

occur with

the

peak values

of the

anticipated alternating signal.

The

computer programs Offset Error Determination

and

Worst Case Drift Perfor-

mance (Appendix A.5 and A.6)

can be

used

to

check

for

this.

2.

The

blocking capacitors must have sufficiently high values that

the

lowest required signal frequency

is not

attenuated excessively.

The

second

stage

of

Figure

3-3 has

effectively become

the

high pass filter

of

Figure

5-3,

which will

be

discusse ...