Grounding - Seagate ST11200N Product Manual

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10.2.1.2 Termination
The reference index signal (REFIND+) is terminated with a 7.5 K ohm resistor. Each drive has a termination
resistor located on the Main PCB. The terminator resistor is not removable and is always in the circuit.
10.2.1.3 Physical interface
The dimensions of the connector (J6) mounted on the Main PCB to interconnect the drives is shown in
Figure 10.2.1-2. It is a 12 pin, 6 jumper position gold header type connector. Only pins 5 and 6 are used for
connecting the Reference Index signal cable, as shown in Figure 10.2.1-2. Pin 6 is REFIND+ and Pin 5 is
ground.
.157
+/- .010
Figure 10.2.1-2. Configuration select header specification. (Connector used has 12 pins).
The interface physical characteristics for the "NC" models are given in Figure 11.6.3-1b and Table 11.6.3-1c.
The "Sync" signal is included among the 80 pins of the I/O connector.
10.3

Grounding

Signal ground (PCB) and HDA ground are connected together in the Hawk 1 drive and cannot be separated
by the user. The equipment in which the drive is mounted is connected directly to the HDA and PCB with no
electrically isolating shock mounts. If it is desired for the system chassis to not be connected to the HDA/
PCB ground, the systems integrator or user must provide a nonconductive (electrically isolating) method of
mounting the drive in the host equipment.
Product Manual - Hawk 1 Family SCSI-2 (Volume 1), Rev. D
.485 max
.020 +/- .001
(square)
.0787 typ
.0787
typ
.394 +/- .010
.157
+/- .010
.236 max .090
-.128
.048 min
.033 +/- .004