API7721FS-13

API7721FS-13 combines the two API772X options that matter for bidirectional safety links: the 7721 channel split (channel A reversed, 1 forward / 1 reverse) plus the F fail-safe option, so both outputs default low when an input is open or the input side loses power. For isolated CAN, UART or transceiver interfaces this means a dead controller side cannot leave the isolated side driving a false active level. The device sits in the narrow SO-8 (Type CJ2) with 3750VRMS UL 1577 isolation, more than 4mm creepage and clearance, a comparative tracking index above 600 and barrier capacitance of only about 0.5pF, which keeps common-mode coupling low. Speed and drive are unchanged from the family: 100Mbps maximum, 2.5V to 5.5V supplies on both sides, 150kV/us minimum CMTI, 11ns typical propagation delay, plus/minus 15mA output drive limits and -40 to +125C operation. Selection advice: choose this code when a 1/1 isolated link must fail low; choose API7721S-13 for the same pinout with default-high behaviour, or API7722FS-13 if the reverse channel has to be B instead of A. It is ordered as 4000 pieces per 13-inch tape and reel with marking 7721F. Parameters verified against Diodes Incorporated documentation.