The ISO654x devices are general purpose functional isolators for cost sensitive, space constrained applications that require isolation for non-safety applications. The isolation barrier supports a working voltage of 400VRMS / 566VDC and transient over voltages of 707VRMS / 1000VDC . The ISO654x devices provide high EMC performance while isolating CMOS or LVCMOS digital I/Os. ISO654x uses SiO2 as the isolation barrier. Each isolation channel has a logic input and output buffer separated by the insulation barrier. These devices come with enable pins that can be used to put the respective outputs in high impedance. The ISO6540 and ISO6540F devices have all channels in the forward direction. The ISO6541 and ISO6541F devices have one reverse-direction channel. The ISO6542 and ISO6542F devices have two reverse-direction channels. In the event of input power or signal loss, the default output is high for devices without the suffix F and low for devices with the suffix F. See Device Functional Modes for further details. These devices help prevent noise currents on GPIOs or data buses such as SPI, UART RS-485, RS-232, and CAN from causing data corruption or damaging sensitive circuitry. Through chip design and layout techniques, the electromagnetic compatibility of the devices have been significantly enhanced to ease system-level design.