Table 9. pwm duty vs register setting, 18 registers 67-69h: temperature limit, Table 10. temperature limit vs register setting – Rainbow Electronics LM85 User Manual
Page 21: Functional description
Functional Description
(Continued)
TABLE 9. PWM Duty vs Register Setting
Current Duty
Value (Decimal)
Value (Hex)
0%
0
00h
0.3922%
1
01h
.
.
.
.
.
.
.
.
.
25.098%
64
40h
.
.
.
.
.
.
.
.
.
50.196%
128
80h
.
.
.
.
.
.
.
.
.
100%
255
FFh
4.18 Registers 67-69h: Temperature Limit
Register
Address
Read/
Write
Register
Name
Bit 7
(MSB)
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
(LSB)
Default
Value
Lock?
67h
R/W
Zone1 Fan Temp Limit
7
6
5
4
3
2
1
0
5Ah
U
68h
R/W
Zone2 Fan Temp Limit
7
6
5
4
3
2
1
0
5Ah
U
69h
R/W
Zone3 Fan Temp Limit
7
6
5
4
3
2
1
0
5Ah
U
These are the temperature limits for the individual zones. When the current temperature equals this limit, the fan will be turned
on if it is not already. When the temperature exceeds this limit, the fan speed will be increased according to the algorithm set forth
in the Auto Fan Range, PWM Frequency register description. Default = 90˚C = 5Ah
This register becomes Read Only when the Ready/Lock/Start/Override register Lock bit is set. Any further attempts to write to this
register shall have no effect. After power up the default value is used whenever the Ready/Lock/Start/Override register Start bit
is cleared even though modifications to this register are possible.
TABLE 10. Temperature Limit vs Register Setting
Temperature
Reading (Decimal)
Reading (Hex)
−127˚C
−127
81h
.
.
.
.
.
.
.
.
.
−50˚C
−50
CEh
.
.
.
.
.
.
.
.
.
0˚C
0
00h
.
.
.
.
.
.
.
.
.
50˚C
50
32h
.
.
.
.
.
.
.
.
.
127˚C
127
7Fh
LM85
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