FDD Timing
t3
nDIR
t4
t1
t2
nSTEP
nDS0-3
nINDEX
nRDATA
t5
t6
t7
t8
nWDATA
nIOW
t9
t9
nDS0-1,
nMTR0-1
(AT Mode timing only)
Parameter
min
typ
max
units
t1
t2
t3
t4
t5
t6
t7
t8
t9
nDIR Set Up to nSTEP Low
nSTEP Active Time Low
nDIR Hold Time After nSTEP
nSTEP Cycle Time
nDS0-1 Hold Time from nSTEP Low
nINDEX Pulse Width
nRDATA Active Time Low
nWDATA Write Data Width Low
nDS0-1, MTR0-1 from End of nIOW
4
24
96
132
20
2
40
.5
25
X*
X*
X*
X*
X*
X*
ns
Y*
ns
*X specifies one MCLK period and Y specifies one WCLK period.
MCLK = 16x Data Rate (at 500 Kbp/s MCLK = 8 MHz)
WCLK = 2x Data Rate (at 500 Kbp/s WCLK = 1 MHz)
FIGURE 8 - DISK DRIVE TIMING
SMSC DS – FDC37N769
Page 120 of 137
Rev. 02-16-07
DATASHEET
SMSC [ SMSC CORPORATION ]
