Input

20 k

Ω

Output

LM111, LM211, LM311

SLCS007I – SEPTEMBER 1973 – REVISED JUNE 2015

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9 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. Validate and test

the design implementation to confirm system functionality.

9.1 Application Information

A typical LMx11 application compares a single signal to a reference or two signals against each other. Many

users take advantage of the open-drain output to drive the comparison logic output to a logic voltage level to an

MCU or logic device. The wide supply range and high voltage capability makes LMx11 optimal for level shifting to

a higher or lower voltage.

9.2 Typical Application

Figure 13. Zero-Crossing Detector

9.2.1 Design Requirements

For this design example, use the parameters listed in Table 1 as the input parameters.

Table 1. Design Parameters

PARAMETER

MIN

TYP

MAX

UNIT

Input voltage range

–15

13

V

Positive supply voltage

15

V

Negative supply voltage

–15

Output current

20

mA

9.2.2 Detailed Design Procedure

When using LMx11 in a general comparator application, determine the following:

•

Input voltage range

•

Minimum overdrive voltage

•

Output and drive current

•

Response time

9.2.2.1 Input Voltage Range

outside of this range can yield incorrect comparisons.

The following list describes the outcomes of some input voltage situations.

12

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