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ISO1640 ACTIVE Hot-swappable, robust-EMC bidirectional I2C isolator with bidirectional clock Pin-to-pin upgrade with hot-swap capability and improved EMC

Product details

Rating Catalog Isolation rating Basic Number of channels 2 Serial data Bidirectional Serial clock Bidirectional Data rate (max) (Mbps) 1 Working isolation voltage (VIOWM) (Vrms) 400 Surge isolation voltage (VIOSM) (VPK) 4000 Transient isolation voltage (VIOTM) (VPK) 4242 Withstand isolation voltage (VISO) (Vrms) 2500 CMTI (min) (kV/µs) 25 Supply voltage (max) (V) 5.5 Supply voltage (min) (V) 3 Operating temperature range (°C) -40 to 125
Rating Catalog Isolation rating Basic Number of channels 2 Serial data Bidirectional Serial clock Bidirectional Data rate (max) (Mbps) 1 Working isolation voltage (VIOWM) (Vrms) 400 Surge isolation voltage (VIOSM) (VPK) 4000 Transient isolation voltage (VIOTM) (VPK) 4242 Withstand isolation voltage (VISO) (Vrms) 2500 CMTI (min) (kV/µs) 25 Supply voltage (max) (V) 5.5 Supply voltage (min) (V) 3 Operating temperature range (°C) -40 to 125
SOIC (D) 8 29.4 mm² 4.9 x 6
  • Isolated bidirectional, I2C compatible, communication
  • Supports up to 1-MHz operation
  • 3-V to 5.5-V supply range
  • Open-drain outputs With 3.5-mA Side 1 and 35-mA Side 2 sink current capability
  • –40°C to +125°C operating temperature
  • ±50-kV/µs transient immunity (Typical)
  • HBM ESD protection of 4 kV on all pins; 8 kV on bus pins
  • Safety-related certifications:
    • 4242-VPK isolation per DIN EN IEC 60747-17 (VDE 0884-17)
    • 2500-VRMS isolation for 1 minute per UL 1577
    • CSA approval per IEC 62368-1 end equipment standard
    • CQC basic insulation per GB4943.1-2011
  • Isolated bidirectional, I2C compatible, communication
  • Supports up to 1-MHz operation
  • 3-V to 5.5-V supply range
  • Open-drain outputs With 3.5-mA Side 1 and 35-mA Side 2 sink current capability
  • –40°C to +125°C operating temperature
  • ±50-kV/µs transient immunity (Typical)
  • HBM ESD protection of 4 kV on all pins; 8 kV on bus pins
  • Safety-related certifications:
    • 4242-VPK isolation per DIN EN IEC 60747-17 (VDE 0884-17)
    • 2500-VRMS isolation for 1 minute per UL 1577
    • CSA approval per IEC 62368-1 end equipment standard
    • CQC basic insulation per GB4943.1-2011

The ISO1540 and ISO1541 devices are low-power, bidirectional isolators that are compatible with I2C interfaces. These devices have logic input and output buffers that are separated by Texas Instruments Capacitive Isolation technology using a silicon dioxide (SiO2) barrier. When used 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.

This isolation technology provides for function, performance, size, and power consumption advantages when compared to optocouplers. The ISO1540 and ISO1541 devices enable a complete isolated I2C interface to be implemented within a small form factor.

The ISO1540 has two isolated bidirectional channels for clock and data lines while the ISO1541 has a bidirectional data and a unidirectional clock channel. The ISO1541 is useful in applications that have a single controller while the ISO1540 is suitable for multi-controller applications. For applications where clock stretching by the target is possible, the ISO1540 device should be used.

Isolated bidirectional communication is accomplished within these devices by offsetting the low-level output voltage on side 1 to a value greater than the high-level input voltage on side 1, thus preventing an internal logic latch that otherwise would occur with standard digital isolators.

The ISO1540 and ISO1541 devices are low-power, bidirectional isolators that are compatible with I2C interfaces. These devices have logic input and output buffers that are separated by Texas Instruments Capacitive Isolation technology using a silicon dioxide (SiO2) barrier. When used 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.

This isolation technology provides for function, performance, size, and power consumption advantages when compared to optocouplers. The ISO1540 and ISO1541 devices enable a complete isolated I2C interface to be implemented within a small form factor.

The ISO1540 has two isolated bidirectional channels for clock and data lines while the ISO1541 has a bidirectional data and a unidirectional clock channel. The ISO1541 is useful in applications that have a single controller while the ISO1540 is suitable for multi-controller applications. For applications where clock stretching by the target is possible, the ISO1540 device should be used.

Isolated bidirectional communication is accomplished within these devices by offsetting the low-level output voltage on side 1 to a value greater than the high-level input voltage on side 1, thus preventing an internal logic latch that otherwise would occur with standard digital isolators.

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Technical documentation

Design & development

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Evaluation board

ISO154XEVM — ISO154xEVM Evaluation Module

The ISO154xEVM Evaluation Module has been designed to allow the user to evaluate the electrical parameter performance and features of TI's ISO154x family of 3kV I2C isolators which are based on TI's capacitive isolation technology. The ISO154xEVM Evaluation Module provides for the evaluation of:

(...)
User guide: PDF | HTML
Not available on TI.com
Daughter card

MSP-ISO — Isolation Adapter for MSP LaunchPad Development Kits

The MSP-ISO Isolation board is an easy-to-use plug-in module that offers galvanic isolation between the Debug and Target circuits for MSP430 LaunchPad developers. This is important in cases where the debug circuitry may adversely affect the quality of analog signal measurements made by the MSP430 (...)

User guide: PDF
Simulation model

ISO1540 IBIS Model

SLLM189.ZIP (31 KB) - IBIS Model
Reference designs

TIDA-00018 — Temperature Sensor Interface Module for Programmable Logic Controllers (PLC)

The TIDA-00018 reference design enables faster development of high precision temperature measurement solutions using 24-Bit delta-sigma ADC and most widely used temperature sensors like thermocouple and RTD. The design guide will address the sensor signal conditioning, thermocouple cold junction (...)
Design guide: PDF
Schematic: PDF
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