Seagate ST43401N/ND, ST43402ND user manual Grounding the system, Synchronizing the spindle

ST43401N/ND, ST43402ND User’s Manual, Rev. B 37

Grounding the system

Grounding the system through the power cables and I/O cables is usually sufficient to protect against noise and emissions.

Synchronizing the spindle

The spindle sync feature makes it possible to synchronize the spindle rotation of a group of disc drives. This reduces the latency normally encountered when the initiator switches between multiple disc drives.

Figure 19 shows two system configurations. In one type of system, one of the disc drives in the system provides the reference clock. In the other type, an external signal source provides the reference clock.

Internal Source

Spindle

SyncJ05

Cable

T

Drive

SP

Select

Plug

J05

Drive

(master)

✴

J05

Drive

SP

32 loads

maximum

J05

Drive

	T
Terminator
	SP

	External Source
Spindle
			Signal Source
Sync
Cable
		T

J05

Drive

SP

J05

Drive

SP

32 loads

maximum

J05

Drive

	T
Terminator
	SP

✴Master designated by jumper or by initiator

Figure 19. System diagram for spindle sync