It passes signals across a 2500Vrms isolation barrier at data rates up to 25Mbps with typical rise/fall times of 1ns.
That figure matters in motor-drive environments where PWM switching couples fast voltage edges across the barrier — below that threshold, the output can glitch. The 25kV/µs rating is typical for this class and sufficient for most industrial drives; if you are working in a high-noise traction inverter or solar inverter, the ISO7721FBDWR offers 85kV/µs CMTI and 5kVrms isolation.
