Hitachi HDS721050CLA362 Specifications page 26

The enclosure shall be capable of supplying 2.4 A peak on each 12 V pre-charge pin (R=5 Ohms).+5 Vdc power that is
available on the extended pins. This is used for pre-charging the I/O module.
The enclosure shall provide for a current limit of 4.5 A peak on each 5V pre-charge pin (R=1.1 Ohms).These signals are
the inbound high-speed differential signals that are connected to the serial ATA cable.
HITACHI Deskstar & CinemaStar 7K1000.B & Deskstar E7K1000 Hard Disk Drive specification
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