SN75971B,pdf(SCSI Differential

The SN75971B SCSI differential converter-data is a 9-channel RS-485 transceiver. When used in conjunction with its companion control transceiver, the SN75970B, the resulting chip set provides the superior electrical performance of differential SCSI from a single-ended SCSI bus or controller. A 16-bit Ultra-SCSI (or Fast-20) SCSI bus can be implemented with just three devices (two data and one control) in the space efficient, 56-pin, shrink small-outline package (SSOP) or thin shink small outline package (TSSOP) and a few external components. An 8-bit SCSI bus requires only one data and one control transceiver.

The SN75971B is available in a B2 (20 Mxfer) version and a B1 (10 Mxfer) version.

In a typical differential SCSI node, the SCSI controller provides an enable for each external RS-485 transceiver channel.