8-channel SPI isolator with 500VAC isolation
The Infineon ISOFACE™ ISO1I811TXUMA1 is an 8-channel digital isolator with an SPI interface, using magnetic coupling technology for the isolation barrier. It provides unidirectional signal transfer across a 500VAC isolation rating, with all eight channels on the input side (side 1) and none on side 2 — this is a pure SPI master-side isolator, not a bidirectional transceiver.
25kV/µs common-mode transient immunity — motor-drive fit
A fast-switching IGBT or SiC MOSFET stage can slam the isolation barrier with dv/dt rates in the tens of kV/µs; if the isolator's CMTI is too low, data corruption or latch-up follows. At 25kV/µs minimum, this ISOFACE™ part clears the requirement for most industrial drives up to several hundred volts DC bus, though a 600V+ SiC half-bridge running at 50+ kV/µs would need a part with higher margin. The magnetic coupling technology handles this transient without the pulse-width distortion that can plague optocoupler-based designs at high slew rates.
The 2.85V to 5.5V supply span lets it interface directly with 3.3V MCUs on one side and 5V peripherals on the other, though the unidirectional channel arrangement means you need to plan the SPI signal direction: the 8/0 input-side count tells you all eight channels face the same way, so the SPI bus's MISO line must be on the same side as MOSI, SCK, and CS — not a problem for a master-side isolator where the MCU drives everything, but worth flagging if your bus has bidirectional data lines.
Package, compliance, and lifecycle
The 48-TSSOP supplier device package is the same 6.10mm-wide body used across Infineon's ISOFACE™ family, which means a layout designed for one member can often accommodate a pin-compatible sibling if a second-source or higher-channel-count variant is needed later. No isolated power is integrated — the part is a signal-only isolator, so the SPI-side and isolated-side circuits each need their own local supply rail.