MAX31785 MAXIM [Maxim Integrated Products], MAX31785 Datasheet - Page 43

• Manufacturer Part Number: MAX31785
• Description: 6-Channel Intelligent Fan Controller
• Manufacturer: MAXIM [Maxim Integrated Products]

The TEMPERATURE STEP sets the temperature in degrees Celsius and represents a threshold level at which the
device updates the fan PWM duty cycle setting. The 2 data bytes are in DIRECT format. The valid temperature range
depends on the temperature sensor.
The MFR_FAN_LUT command is used to configure the LUT that controls the fan. The fan has an LUT that maps eight
programmable temperature levels to eight programmable fan PWM duty-cycle levels (bit 6 in FAN_CONFIG_1_2 is
zero) or eight programmable target fan speeds (bit 6 in FAN_CONFIG_1_2 is one). The LUT allows a wide variety of
profiles to be used.
USER NOTE: The programmable configuration of MFR_FAN_LUT must be monotonic.
Table 27. MFR_FAN_LUT
Table 28. Valid Temperature Range
Page 12: Internal Temp Sensor
Pages 13 to 16: I
Page 6 to 11: Remote Thermal Diode Temp Sensor
BYTE NUMBER
10-11
12-13
14-15
16-17
18-19
20-21
22-23
24-25
26-27
28-29
30-31
0-1
2-3
4-5
6-7
8-9
2
C Remote Temp Sensor
TEMPERATURE SENSOR
6-Channel Intelligent Fan Controller
SPEED STEP 0
SPEED STEP 1
SPEED STEP 2
SPEED STEP 3
SPEED STEP 4
SPEED STEP 5
SPEED STEP 6
SPEED STEP 7
WORD NAME
TEMP STEP 0
TEMP STEP 1
TEMP STEP 2
TEMP STEP 3
TEMP STEP 4
TEMP STEP 5
TEMP STEP 6
TEMP STEP 7
TEMPERATURE STEP: Temperature Level Setting
Temperature for step 0.
Fan PWM duty cycle or fan speed for step 0.
Temperature for step 1.
Fan PWM duty cycle or fan speed for step 1.
Temperature for step 2.
Fan PWM duty cycle or fan speed for step 2.
Temperature for step 3.
Fan PWM duty cycle or fan speed for step 3.
Temperature for step 4.
Fan PWM duty cycle or fan speed for step 4.
Temperature for step 5.
Fan PWM duty cycle or fan speed for step 5.
Temperature for step 6.
Fan PWM duty cycle or fan speed for step 6.
Temperature for step 7.
Fan PWM duty cycle or fan speed for step 7.
-55NC to +125NC
-40NC to +120NC
VALID RANGE
-40NC to +85NC
MEANING
MFR_FAN_LUT (F2h)
43