RHF350 STMICROELECTRONICS [STMicroelectronics], RHF350 Datasheet - Page 16

• Manufacturer Part Number: RHF350
• Description: Rad-hard 550 MHz low noise operational amplifier
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

Inverting amplifier biasing
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Inverting amplifier biasing
A resistance is necessary to achieve good input biasing, such as resistance R shown in
Figure 28
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:
Equation 11
Figure 28. Compensation of the input bias current
.
I
ib
-
R
in
Doc ID 15604 Rev 4
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
Load
AM00839
RHF350