Texas Instruments' ISO734x provides galvanic isolation up to 3000 VRMS for 1 minute per UL and 4242 VPK per VDE. These devices have four isolated channels comprised of logic input and output buffers separated by a silicon dioxide (SiO2) insulation barrier. ISO7340 has four channels in forward-direction, ISO7341 has three forward and one reverse-direction channels; and ISO7342 has two forward- and two reverse-direction channels. In case of input power or signal loss, default output is ‘low’ for devices with suffix ‘F’ and ‘high’ for devices without suffix ‘F’.
Used in conjunction with isolated power supplies, these devices prevent noise currents on a data bus or other circuits from entering the local ground and interfering with or damaging sensitive circuitry. ISO734x has integrated noise filtering for harsh industrial environment where short noise pulses may be present at the device input pins. ISO734x has TTL input thresholds and operates from 3 V to 5.5 V supply levels. Through innovative chip design and layout techniques, electromagnetic compatibility of ISO734x has been significantly enhanced to enable system-level ESD, EFT, surge and emissions compliance.