Datasheet

6-Channel Intelligent Fan Controller
MAX31785
4
TABLE OF CONTENTS (continued)
MFR _DATE (9Dh) ...........................................................................34
MFR_SERIAL (9Eh)
..........................................................................34
MFR_MODE (D1h)
...........................................................................35
MFR_VOUT_PEAK (D4h)
.....................................................................36
MFR_TEMPERATURE_PEAK (D6h)
.............................................................36
MFR_VOUT_MIN (D7h)
.......................................................................36
MFR_FAULT_RESPONSE (D9h)
................................................................36
MFR_NV_FAULT_LOG (DCh)
..................................................................37
MFR_TIME_COUNT (DDh)
....................................................................40
MFR_TEMP_SENSOR_CONFIG (F0h)
...........................................................40
MFR_FAN_CONFIG (F1h)
.....................................................................41
MFR_FAN_LUT (F2h)
........................................................................43
TEMPERATURE STEP: Temperature Level Setting
..................................................43
FAN SPEED STEP: Fan PWM Duty Cycle or Fan Speed Setting
.......................................44
MFR_READ_FAN_PWM (F3h)
.................................................................45
MFR_FAN_FAULT_LIMIT (F5h)
.................................................................45
MFR_FAN_WARN_LIMIT (F6h)
.................................................................45
MFR_FAN_RUN_TIME (F7h)
...................................................................46
MFR_FAN_PWM_AVG (F8h)
...................................................................46
MFR_FAN_PWM2RPM (F9h)
..................................................................46
Applications Information
........................................................................ 46
Power-Supply Decoupling
.....................................................................46
Open-Drain Pins
............................................................................46
Typical Operating Circuit
....................................................................... 47
Package Information
........................................................................... 47
Revision History
.............................................................................. 48
Figure 1. Automatic Fan Control
.................................................................. 23
Figure 2. Fan Speed Example
................................................................... 23
Figure 3. Fan Spin-Up
......................................................................... 24
Figure 4. Fan PWM to RPM Example
.............................................................. 25
Figure 5. MFR_NV_FAULT_LOG
................................................................. 37
Figure 6. Fan Lookup Table (LUT) Format
..........................................................44
LIST OF FIGURES