The high density 68 pin SCSI II/III connector is being used for purposes other than SCSI interfaces because of board and front panel space limitations. For example in the PMC environment the SCSI connector provides an excellent size and pin count for the front panel space allowed. The SCSI connector while dense, is not easy to connect to with wiring intended to go to multiple locations.
HDEterm68 terminal provides an easy way to get from a high density SCSI connector to discrete wires. For example with the PMC-Parallel-TTL design a standard SCSI II cable can be used to connect the PMC to the HDEterm68, and then to the system wiring via the terminal strips provided. HDEterm68 provides a space efficient, low cost method of interconnecting the control electronics to the rest of the sensors, IO, machinery etc.
HDEterm68 comes with two SCSI II/III compatible connectors. One connector could be used for a termination plug or for a second SCSI cable. The screw terminals could then be used as testpoints. The SCSI connectors are connected to the screw terminals and to each other 1:1. The "in" SCSI connector is connected to the screw terminals and then to the "out" connector. The SCSI connectors can be right angle "-H" or verticle "V" or mixed "-M".
The SCSI connectors and terminal block are interconnected with differentially routed matched length traces. The traces have two sets of resistor packs in series to allow isolation of the terminal block or second SCSI connector from the "input" connector [P1]. The standard configuration is to have both sets installed with all three devices connected. The routing is matched from P1 to the terminal block and from P1 to P2 or from the terminal block to P2.
In addition two header strips are available to allow for loop-back and custom terminations. The first header "TP1" is tied via 0805 resistors to P1 [primary SCSI connector]. The resistors are optionally installed to allow direct connection or terminated connection, resistive, capacitative etc. to the header strip. The second header strip "TP2" is tied to the terminal block. The isolation resistors between P1 and the terminal block can be left uninstalled and the path through the TP1 header used to allow for wiring options and other added circuitry. Please note that TP1 and TP2 are installed by customer request.
Additional features include: power entry and distribution posts, oscillator, regulator, LED and transceiver positions. Please send us your specifications. We will assign a modified part number and build a custom terminal block for you.
Connectors
2 - SCSI II/III compatible with cable locks
SCSI connectors can be vertical, horizontal or mixed. Please specify -V, -H or -M
2 row by 34 terminal strip with side entry wires and top screw lock. Rows are offset for ease of access.
Available with plastic and DIN rails -P or as shown for bench top operation.
Also available without the plastic and terminal block for a low cost loop-back fixture.
Weight:
With plastic: 10.5oz
Without plastic: 6.5oz
The HDEterm68 mechanical mouting data is available with the HDEterm68 Mechanical Dimensions drawing. Locations and dimensions of the mounting holes and board, height with and without plastic are included.
A schematic for the HDEterm68 is provided to show the possibilities for terminations, loop-back, signal sources etc.
Reference HDEterm68 Schematic
