W83792G Nuvoton Technology Corporation of America, W83792G Datasheet - Page 59

• Manufacturer Part Number: W83792G
• Description: IC MONITOR H/W 48-LQFP
• Manufacturer: Nuvoton Technology Corporation of America

Specifications of W83792G

• Function: Hardware Monitor
• Topology: ADC, Fan Control, Register Bank
• Sensor Type: External
• Sensing Temperature: External Sensor
• Output Type: I²C™
• Output Alarm: Yes
• Output Fan: Yes
• Voltage - Supply: 4.5 V ~ 5.5 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 48-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Fan 1/2/3 Smart Fan II Temperature/ Duty Cycle setups -- Index E0h~EBh 5Fh(Bank 0), continued.
Reset Condition: Resume Reset, INIT.
W83792D also provides a special mode for FAN. It’s called Smart Fan II mode. In this mode,
W83792D will output fix cycles when related temperature sensors detects the temperature in preset
temperature region. Their relation looks like the following figure.
5Fh specifies a temperature point, if any temperature sensor is sensed above this, all FAN will be
push to full speed. Default is 127 degree, that means, this is disabled, since no temperature can
higher than 127 degree in W83792D.
In Register E0h-EBh defines the relationship of temperature and duty cycle. Also previous Target
Temperature and Non-Stop Duty Cycle are used as Temperature Point 1 and minimum duty cycle.
To prevent FAN Duty Cycle from throttling at Temperature Point, Temperature Tolerances(87h, 97h)
are used to provide a hysterisis mechanism. When temperature is going up (Blue Line), duty cycle
changes only when temperature reaches Temperature Point + Tolerance. On the contrary, when
temperature is going low (Green Line), duty cycle changes only when sensor temperature down to
Temperature Point – Tolerance.
FAN 3 Temperature Point 2
FAN 3 Temperature Point 3
FAN 3 Temperature Point 4
All FAN on Temperature
Mnemonic
Point
Non-Stop Duty Cycle
Fan Duty Cycle 100%
Fan Duty Cycle Level 3
Fan Duty Cycle Level 2
Fan Duty Cycle Level 1
Fan Duty Cycle
Bank
0
0
0
0
Index
EA
EB
E9
5F
Temp. Tolerance
Temp. 1
Attr
RW
RW
RW
RW
reserve
reserve
reserve
reserve
BIT 7
0
0
0
0
Temp.2
- 53 -
BIT 6
Temperature point above this will turn all FAN to full
Temp.3
BIT 5
Publication Release Date: April 26, 2006
W83792AD/AG/D/G
BIT 4
Temperature Point 2
Temperature Point 3
Temperature Point 4
Temp.4
speed
BIT 3
3Ch
7Fh
28h
50h
BIT 2
Temperature
BIT 1
Revision 0.9
BIT 0