Hitachi HDS723020BLA642 Specifications page 27

6.1.2.4
12V PRECHARGE
+12 Vdc power that is available on the extended pins. This is used for pre-charging the 12V circuitry in the I/O Option slot
module.
The enclosure shall be capable of supplying 2.4 A peak on each 12 V pre-charge pin (R=5 Ohms). These signals are the
inbound high-speed differential signals that are connected to the serial ATA cable.
Hitachi hard disk drive specifications
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