DocID022943 Rev 3

13/25

LMX321, LMX358, LMX324

Application information

4

Application information

4.1

Operating voltages

The LMX321, LMX358, and LMX324 can operate from 2.3 V to 5.5 V. The devices’

parameters are fully specified for 2.7 V and 5 V power supplies. Additionally, the main

specifications are guaranteed in extended temperature ranges from -40° C to +125° C.

4.2

Input common-mode range

The LMX321, LMX358, and LMX324 have an input common-mode range that includes

output phase reversal.

4.3

Rail-to-rail output

The operational amplifiers’ output levels can go close to the rails: to a maximum of 180 mV

above and below the rail when connected to a 10 k

4.4

Input offset voltage drift over temperature

The maximum input voltage drift over the temperature variation is defined in Equation 1.

Equation 1

4.5

PCB layouts

For correct operation, it is advised to add 10 nF decoupling capacitors as close as possible

to the power supply pins.

4.6

Macromodel

Accurate macromodels of the LMX321, LMX358, and LMX324 are available on

STMicroelectronics’ web site at www.st.com. These models are a trade-off between

accuracy and complexity (that is, time simulation) of the LMX321, LMX358, and LMX324

operational amplifiers. They emulate the nominal performances of a typical device within the

specified operating conditions mentioned in the datasheet. They also help to validate a

design approach and to select the right operational amplifier, but they do not replace

on-board measurements.

ΔVio

ΔT

------------

max Vio T

() Vio 25° C

()

–

T25

° C

–

----------------------------------------------------

=