ADT7463 Analog Devices, ADT7463 Datasheet - Page 16

• Manufacturer Part Number: ADT7463
• Description: Dbcool Thermal Management Controller And Voltage Monitor
• Manufacturer: Analog Devices

AN-613
STEP 8: DETERMINING THE OPERATING POINT FOR
EACH TEMPERATURE CHANNEL
The operating point for each temperature channel is the
optimal temperature for that thermal zone. The hotter
each zone is allowed to be, the quieter the system since
the fans are not required to run at 100% all of the time.
The ADT7460/ADT7463 will increase/decrease fan
speeds as necessary to maintain operating point tem-
perature. This allows for system-to-system variation
and removes the need for worst-case design. As long as
a sensible operating point value is chosen, any T
value can be selected in the system characterization. If
the T
required, and the temperature will be below the operat-
ing point. In response, the ADT7460/ADT7463 will
increase T
MIN
value is too low, the fans will run sooner than
MIN
AMBIENT TEMP
to keep the fans off for longer and allow
REMOTE 1 =
REMOTE 2 =
VRM TEMP
CPU TEMP
LOCAL =
Figure 21. Operating Point Value Dynamically Adjusts Automatic Fan Control Settings
THERMAL CALIBRATION
T
T
T
THERMAL CALIBRATION
THERMAL CALIBRATION
MIN
MIN
MIN
T
T
T
RANGE
RANGE
RANGE
100%
0%
100%
100%
0%
0%
OPERATING
POINT
MUX
MIN
PWM
MIN
–16–
PWM
MIN
PWM
MIN
TACHOMETER 1
RAMP CONTROL
ENHANCEMENT)
MEASUREMENT
RAMP CONTROL
RAMP CONTROL
ENHANCEMENT)
ENHANCEMENT)
TACHOMETER 2
MEASUREMENT
TACHOMETER 3
MEASUREMENT
(ACOUSTIC
the temperature zone to get closer to the operating
point. Likewise, too high a T
operating point to be exceeded, and in turn, the
ADT7460/ADT7463 will reduce T
earlier to cool the system.
PROGRAMMING OPERATING POINT REGISTERS
There are three operating point registers, one associ-
ated with each temperature channel. These 8-bit
registers allow the operating point temperatures to be
programmed with 1°C resolution.
OPERATING POINT REGISTERS
Reg. 0x33 Remote 1 Operating Point = 0x64 (100°C)
Reg. 0x34 Local Temp Operating Point = 0x64 (100°C)
Reg. 0x35 Remote 2 Operating Point = 0x64 (100°C)
(ACOUSTIC
(ACOUSTIC
AND 4
GENERATOR
GENERATOR
CONFIG
GENERATOR
PWM
CONFIG
CONFIG
PWM
PWM
PWM
PWM
PWM
PWM1
TACH1
PWM2
TACH2
PWM3
TACH3
MIN
MIN
value will cause the
to turn the fans on
CPU
FAN SINK
FRONT
CHASSIS
REAR
CHASSIS
REV. 0