1 Introduction
This User’s Guide details the ISO154x Evaluation Module (EVM) operation of the factory-installed ISO1540 and
ISO1541 I
2
C-compatible bidirectional isolators. The EVM may be reconfigured for use with two ISO1540 or two
ISO1541 instead of one of each.
This Guide presents a typical laboratory setup used with this EVM.
CAUTION
This Evaluation Module (EVM) is made available for isolator parameter performance evaluation
only and is not intended for isolation voltage testing. To prevent damage to the EVM, any voltage
applied as a supply or digital input/output must be maintained within the 0 V to 5.5 V recommended
operating range.
Exceeding the specified input voltage range may cause unexpected operation and irreversible damage to
the EVM. If there are questions concerning the input voltage range, contact a TI field representative prior to
connecting power.
Applying loads outside the specified output range may result in unintended operation and possible permanent
damage to the EVM. If there is uncertainty as to the load specification, contact a TI field representative.
1.1 Overview
The ISO154x devices are low-power, bidirectional isolators that are compatible with I
2
C interfaces. The logic
input and output buffers on these devices are separated by TI’s Isolation technology utilizing a silicon dioxide
(SiO
2
) barrier. When used in conjunction with isolated power supplies, these devices block high voltages, isolate
grounds and prevent noise currents from entering the local ground and interfering with or damaging sensitive
circuitry.
The ISO1540 has two isolated bidirectional channels for clock and data lines and is fit for multi-master
applications. The ISO1541 has a bidirectional data and a unidirectional clock channel and is useful in
applications that have a single master.
These devices achieve isolated bidirectional communication by introducing an offset, making the side 1 low-level
output greater than the side 1 low-level input and thus preventing an internal logic latch that otherwise would
occur with standard digital isolators.
1.2 ISO154xEVM Kit Contents
1. ISO154xEVM Circuit Board (PWB P/N 6547206)
2. ISO154xEVM User’s Guide (
- this document)
3. ISO154x Datasheet (
1.3 Functional Configuration
The pinouts of ISO1540 and ISO1541 are displayed in
. These devices have an input noise-filter that
prevents transient pulses of up to 5 ns from being passed to the output of the device.
Introduction
2
ISO154xEVM Low-Power Bidirectional I
2
C Isolators Evaluation Module
SLLU166A – JUNE 2012 – REVISED SEPTEMBER 2022
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