1. Default Channel Output State: When the input side is powered down or left floating, the corresponding channel of the BB variant defaults to a low-level output, whereas the EB variant defaults to a high-level output. This is fundamentally a difference in failsafe logic—the BB features a low‑active safe state, while the EB implements a high‑active safe state. 2. In applications involving safety shutdown, enable control, or status monitoring, the acceptability of the logic polarity inversion must be evaluated. If the original circuit relies on the default low level as the safe state, direct replacement may lead to abnormal power‑up behavior or failure of the safety logic. Note: Both devices are identical in electrical parameters, package, temperature rating, and reliability certifications. The difference lies solely in the internal logic design, making them functional variants within the same product family.