W83782D Datasheet, PDF (24/73 Pages) Winbond – MONITORING IC

Preliminary W83782D
The default divisor is 2 and defined at CR47.bit7~4, CR4B.bit7~6, and Bank0 CR5D.bit5~7 which are
three bits for divisor. That provides very low speed fan counter such as power supply fan. The
followed table is an example for the relation of divisor, PRM, and count.
Divisor
1
2 (default)
4
8
16
32
64
128
Nominal
PRM
8800
4400
2200
1100
550
275
137
68
Time per
Revolution
Counts
6.82 ms
153
13.64 ms
153
27.27 ms
153
54.54 ms
153
109.08 ms
153
218.16 ms
153
436.32 ms
153
872.64 ms
153
Table 1.
70% RPM
6160
3080
1540
770
385
192
96
48
Time for 70%
9.74 ms
19.48 ms
38.96 ms
77.92 ms
155.84 ms
311.68 ms
623.36 ms
1246.72 ms
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