Hi:
I am a consultant looking at the Savvio 10k.5 SAS HDD. I am studying Fig. 4 in
http://www.seagate.com/staticfiles/support/docs/manual/enterprise/savvio/10K.5/100628561f.pdf. I have a few questions. If you wouldn't mind, please answer them.
Does C2 represent the current pulses out of the 12 DC supply at the terminal of the HDD? It looks like F1 is an averaged value of C2; is this correct? What does "eres" stand for?
At about 1.3 s after the red diamond location the average current does a kind of dying oscillation. Does this correspond to initiating a rotor position before beginning the spin up? The F1 current kind of jumps up and then rises with a slope to a peak current. I guess the current is gradually increasing while the motor spins up. Why does one do that? Following the current peak at about 1.9 s, the current gradually decreases; is this due to the back emf build up? At about 2.15 s the red F1 current reaches zero. Is this the point where spindle motor spin-up is complete?
Thank you very much for your attention,
Art Wagner
