Models: DFMS-Sxx

Power Connector

The DC power connector used on all models (50, 68, and 80 pin SCA) are an integral portion of the 50/68 pin SCSI unitized connectors or the 80 pin single connector attachment (SCA) connector.

Power connector pin assignments

SCSI bus connectors

DFMS has different model types that support 50 or 68 pin SCSI connectors in either single-ended or differential driver/receiver configurations. Also supported is the 80 pin SCA in a single-ended driver/receiver configuration.

50 pin signal connector

50 pin models use an AMP PN 84160-1 connector. The connector is compatible with the ANSI SCSI "A" connector specifications. It is limited to 8-bit data transfer only.

Electrical connectors (rear view) 50 pin models

68 pin signal connector

68 pin models use AMP connector (PN 786963-1) that is compatible with the ANSI SCSI "P" connector specifications. It can transfer data in both 8-bit (narrow) and 16-bit (wide) modes.

Electrical connectors (rear view) 68 pin models

Note: The "P" connector is not mechanically compatible with the 50-pin "A" connector as defined in the ANSI SCSI-2 standard. Therefore system cables used with 50 pin products cannot be plugged directly into 68 pin models. Despite the difference in connector, the differential 68 pin models are electrically compatible with differential 50 pin models and other 50 pin differential SCSI products and therefore can coexist on the same bus. In order to do so, the differences in connector types would need to be accounted for in the cable. The same can be said for connecting 68 and 50 pin single-ended models to the same bus. But differential and single-ended models do not work connected to the same bus.

80 Pin (single connector attachment) connector

80 pin SCA models use a molex connector (PN 87091-0001) that is compatible with the specification of: single connector attachment for Small SCSI Disk Drives'. It can transfer data in both 8-bit (narrow) and 16-bit (wide) modes.

Electrical connectors (rear view) 80 pin SCA models

Note: The 'SCA' connector is not mechanically compatible with the 50 pin 'A' connector or the 68 pin 'P' connector as defined in the ANSI SCSI standard. This connector is intended for direct backplane attachment and is not intended to be cable attached to the bus.