SN75LBC775,pdf(Single-Chip App

The SN75LBC775 is a low-power LinBiCMOS^TM device that incorporates the drivers and receivers for an AppleTalk or a LocalTalk interface and a switched-capacitor voltage converter for a single 5-V supply operation. LocalTalk uses a hybrid of RS-422 with the transceiver connected to the network through a small isolation transformer. The AppleTalk mode provides point-to-point communications and uses the same differential driver and receiver as LocalTalk with the addition of a hybrid RS-423, single-ended handshake driver (HSK) and receiver. In the AppleTalk mode, the port connects directly to the receiver with no isolation transformer.

While the device power is turned off (V_CC = 0) or disabled in the LocalTalk mode, the outputs are in a high-impedance state.