SN75970B,pdf(SCSI Differential

The SN75970B SCSI differential converter-control, when used in conjunction with one or more of its companion data transceiver(s), provides the superior electrical performance of differential SCSI from a single-ended SCSI bus controller. A 16-bit, Fast-SCSI bus can be implemented with just three devices (two for data and one for control) in the space-efficient, 56-pin, shrink small-outline package (SSOP) as well as the even smaller TSSOP and a few external components.

The SN75970B is available in a B2 (20 Mxfer) version and a B1 (10 Mxfer) version.

In a typical differential SCSI node, the SCSI controller provides the enables for each external RS-485 transceiver. This could require as many as 27 additional terminals for a 16-bit differential bus controller or relegate a 16-bit single-ended controller to only an 8-bit differential bus.