Half-duplex RS-485 transceiver in 8-SOIC — what to know for the bus
25 Mbps — bus timing and cable-length trade-off
At 25 Mbps the driver edge rate is fast enough that stub lengths on the bus must be kept under 6 inches to avoid reflections; the half-duplex nature means direction control via a GPIO or DE signal is required. For slower speeds (e.g., 250 kbps) the same part works with relaxed layout constraints, but the 25 Mbps rating gives headroom for firmware-upgrade or high-throughput polling schemes.