ADT7476ARQH ONSEMI [ON Semiconductor], ADT7476ARQH Datasheet - Page 36

• Manufacturer Part Number: ADT7476ARQH
• Description: dBCOOL Remote Thermal Controller and Voltage Monitor
• Manufacturer: ONSEMI [ON Semiconductor]

Step 2—Configuring the Mux
the fans can be assigned to particular temperature channels.
Not only can fans be assigned to individual channels, but the
behavior of the fans is also configurable. For example, fans
can be run under automatic fan control, manually (under
software control), or at the fastest speed calculated by
multiple temperature channels. The mux is the bridge
between temperature measurement channels and the three
PWM outputs.
Register 0x5E (PWM configuration registers) control the
behavior of the fans connected to the PWM1, PWM2, and
PWM3 outputs. The values selected for these bits determine
how the mux connects a temperature measurement channel
to a PWM output.
Automatic Fan Control Mux Options
[7:5] (BHVR), Register 0x5C, Register 0x5D, Register
0x5E.
After the system hardware configuration is determined,
Bits [7:5] (BHVR) of Register 0x5C, Register 0x5D, and
AMBIENT TEMP
REMOTE 1 =
REMOTE 2 =
VRM TEMP
CPU TEMP
LOCAL =
THERMAL CALIBRATION
THERMAL CALIBRATION
THERMAL CALIBRATION
T
T
T
MIN
MIN
MIN
Figure 51. Assigning Temperature Channels to Fan Channels
T
T
T
RANGE
RANGE
RANGE
100%
100%
100%
0%
0%
0%
MUX
http://onsemi.com
MUX
36
PWM
PWM
PWM
MIN
MIN
MIN
one PWM output based on multiple temperature channels.
The thermal characteristics of the three temperature zones
can be set to drive a single fan. An example would be the fan
turning on when Remote 1 temperature exceeds 60°C or if
the local temperature exceeds 45°C.
Other Mux Options
[7:5] (BHVR), Register 0x5C, Register 0x5D, Register 0x5E.
CONFIG
CONFIG
CONFIG
The fastest speed calculated options pertain to controlling
TACHOMETER 1
MEASUREMENT
TACHOMETER 2
MEASUREMENT
TACHOMETER 3
MEASUREMENT
PWM
PWM
PWM
000 = Remote 1 temperature controls PWMx
001 = Local temperature controls PWMx
010 = Remote 2 temperature controls PWMx
101 = Fastest speed calculated by local and Remote 2
110 = Fastest speed calculated by all three
011 = PWMx runs full speed
100 = PWMx disabled (default)
111 = Manual mode. PWMx is running under
GENERATOR
GENERATOR
GENERATOR
AND 4
PWM
PWM
PWM
temperature controls PWMx
temperature channels controls PWMx
software control. In this mode, PWM current
duty cycle registers (0x30 to 0x32) are writable
and control the PWM outputs.
ENHANCEMENT)
ENHANCEMENT)
ENHANCEMENT)
(ACOUSTIC
(ACOUSTIC
(ACOUSTIC
CONTROL
CONTROL
CONTROL
RAMP
RAMP
RAMP
PWM1
TACH1
PWM2
TACH2
PWM3
TACH3
FRONT CHASSIS
REAR CHASSIS
CPU FAN SINK