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.
PART NUMBER | PACKAGE | BODY SIZE (NOM) |
---|---|---|
ISO1540 ISO1541 | SOIC (8) | 4.90 mm × 3.91 mm |
Changes from Revision E (March 2019) to Revision F (December 2022)
Changes from Revision D (December 2016) to Revision E (March 2019)
Changes from Revision C (June 2015) to Revision D (December 2016)
Changes from Revision B (May 2013) to Revision C (June 2015)
Changes from Revision A (October 2012) to Revision B (May 2013)
Changes from Revision * (July 2012) to Revision A (October 2012)