Datasheet
V
RF
A
RI
V
1.8
A 3.6
0.5
V
VOUT
A
VIN
Vsup+
+
VOUT
RF
VIN
RI
Vsup-
19
LM158, LM158A
,
LM258
,
LM258A
LM358
,
LM358A
,
LM358B
,
LM2904
,
LM2904B
,
LM2904V
www.ti.com
SLOS068V –JUNE 1976–REVISED SEPTEMBER 2018
Product Folder Links: LM158 LM258 LM258A LM358 LM358A LM358B LM2904 LM2904B LM2904V
Submit Documentation FeedbackCopyright © 1976–2018, Texas Instruments Incorporated
10 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
10.1 Application Information
The LMx58 and LM2904 operational amplifiers are useful in a wide range of signal conditioning applications.
Inputs can be powered before V
S
for flexibility in multiple supply circuits.
10.2 Typical Application
A typical application for an operational amplifier is an inverting amplifier. This amplifier takes a positive voltage on
the input, and makes it a negative voltage of the same magnitude. In the same manner, it also makes negative
voltages positive.
Figure 13. Application Schematic
10.2.1 Design Requirements
The supply voltage must be chosen such that it is larger than the input voltage range and output range. For
instance, this application scales a signal of ±0.5 V to ±1.8 V. Setting the supply at ±12 V is sufficient to
accommodate this application.
10.2.2 Detailed Design Procedure
Determine the gain required by the inverting amplifier using Equation 1 and Equation 2:
(1)
(2)
Once the desired gain is determined, choose a value for R
I
or R
F
. [Subscripts should be fixed in the
accompanying figures and equations also.] Choosing a value in the kilohm range is desirable because the
amplifier circuit uses currents in the milliampere range. This ensures the part does not draw too much current.
This example uses 10 kΩ for R
I
which means 36 kΩ is used for R
F
. This was determined by Equation 3.
(3)