RHF330 STMICROELECTRONICS [STMicroelectronics], RHF330 Datasheet - Page 18

• Manufacturer Part Number: RHF330
• Description: Rad-hard 1 GHz low noise operational amplifier
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

Bias of an inverting amplifier
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Bias of an inverting amplifier
A resistance is necessary to achieve good input biasing, such as resistance R shown in
Figure
The value of this resistance is calculated from the negative and positive input bias current.
The aim is to compensate for the offset bias current, which can affect the input offset voltage
and the output DC component. Assuming I
resistance R is:
Figure 32. Compensation of the input bias current
32.
I
ib
-
R
in
Doc ID 15576 Rev 3
I
ib
+
R
_
+
R
=
ib-
R
----------------------- -
R
, I
R
in
in
V
V
fb
ib+
+
CC
CC
R
R
, R
+
-
fb
fb
in
, R
fb
and a zero volt output, the
Output
Load
AM00839
RHF330