L7250
Table 2. Register map content description (continued)
Bit
SPI field name
Content
REGISTER SR, ADDRESS: 00H
[2:0]
[3]
Rev[2:0]
Revision number of the device, set internally
Thermal warning
ThWarn
ThShutdown
ZCbad
[4]
Thermal shutdown
[5]
Signals a problem with spindle speed loop synchronism
VCM error output in calibration mode
[6]
VCMcalOut
SPNCurrSign
[7]
Spindle current sign to implement adaptive torque optimizer
control
REGISTER VCM1, ADDRESS: 01H
[0]
NoBrake
0=VCM active brake phase enabled
1= VCM active brake phase disabled
[3:1]
Rltimer[2:0]
000 = only Unload1 is enabled
001 = threshold set to 0.4V
010 = threshold set to 0.8V
011 = threshold set to 1.2V
100 = threshold set to 1.6V
101 = threshold set to 2V
110 = threshold set to 2.4V
111 = only Unload2 is enabled
[5:4]
[7:6]
Rlvoltage2[1:0]
Rlvoltage1[1:0]
Selects between 4 values of unload voltage in Unload2 phase:
00 = 1V
01 = 1.125V
10 = 1.250V
11 = 1.375V
Selects between 4 values of unload voltage in Unload1 phase:
00 = 0.375V
01 = 0.5V
10 = 0.625V
11 = 0.75V
REGISTER VCM2, ADDRESS: 02H
[3:0] Rlcalib[3:0]
0111 = 29.4%
0110 = 25.2%
0101 = 21%
0100 = 16.8%
0011 = 12.6%
0010 = 8.4%
0001 = 4.2%
0000 = 0%
1111 = -4.2%
1110 = -8.4%
1101 = -12.6%
1100 = -16.8%
1011 = -21%
1010 = -25.2%
1001 = -29.4%
1000 = -33.6%
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STMICROELECTRONICS [ ST ]
