RHF310 STMICROELECTRONICS [STMicroelectronics], RHF310 Datasheet - Page 17

• Manufacturer Part Number: RHF310
• Description: Rad-hard 400 ?A high-speed operational amplifier
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

RHF310
6
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
R is:
Figure 26. Compensation of the input bias current
26.
I
ib
-
R
in
Doc ID 15577 Rev 3
I
ib
+
R
R
_
+
=
R
---------------------- -
R
ib-
in
in
, I
R
×
+
V
V
fb
ib+
R
R
CC
CC
fb
fb
, R
+
-
in
, R
fb
and a 0 V output, the resistance
Output
Bias of an inverting amplifier
Load
AM00839
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