资 源 简 介
The ADM307xE are 3.3 V, low power data transceivers with ±15 kV ESD protecTIon suitable for full- and half-duplex communicaTIon on mulTIpoint bus transmission lines. They are designed for balanced data transmission, and they comply with TIA/EIA standards: RS-485 and RS-422. The devices have a ⅛ unit load receiver input impedance, which allows up to 256 transceivers on a bus. Because only one driver should be enabled at any time, the output of a disabled or powereddown driver is tristated to avoid overloading the bus. The receiver inputs have a true fail-safe feature, which eliminates the need for external bias resistors and ensures a logic high output level when the inputs are open or shorted. This guarantees that the receiver outputs are in a known state before communication begins and when communication ceases.