21 May
2013
21 May
'13
5:07 p.m.
On 05/21/2013 03:19 PM, Fred Cisin wrote:
Regardless, that was the nub of my comment. The WD1770 and 1772 are not
rated for 8" applications. Some late revisions will work at the higher
frequency. Note that the 1770 and -72 are a "one chip" FDC solution in
a 28-pin package; data separator, write precomp circuitry included under
the epoxy--there is no separate data clock. You're probably thinking of
the NEC 765 type chips.
--Chuck
In most cases
the FDC chip can remain the same, what it needs is a higher
data rate, A faster write clock and a modification to the dat separator
clock. If the FDC is campable of handlign 8" drives, then it can handle
HD 3.5" drives.
Minor nit: That should be clarified/limited as 8" DD
(Machines that handle only 8" SSSD would not be capable)