adt7476a Analog Devices, Inc., adt7476a Datasheet - Page 41

• Manufacturer Part Number: adt7476a
• Description: Dbcool Remote Thermal Controller And Voltage Monitor
• Manufacturer: Analog Devices, Inc.

Mux Configuration Example
This is an example of how to configure the mux in a system
using the ADT7476A to control three fans. The CPU fan sink
is controlled by PWM1, the front chassis fan is controlled by
PWM2, and the rear chassis fan is controlled by PWM3. The
mux is configured for the following fan control behavior:
•
•
•
PWM1 (CPU fan sink) is controlled by the fastest speed
calculated by the local (VRM temperature) and Remote 2
(processor) temperature. In this case, the CPU fan sink is
also being used to cool the VRM.
PWM2 (front chassis fan) is controlled by the Remote 1
temperature (ambient).
PWM3 (rear chassis fan) is controlled by the Remote 1
temperature (ambient).
AMBIENT TEMP
REMOTE 2 =
REMOTE 1 =
VRM TEMP
CPU TEMP
LOCAL =
THERMAL CALIBRATION
THERMAL CALIBRATION
THERMAL CALIBRATION
T
T
T
MIN
MIN
MIN
T
T
T
RANGE
RANGE
RANGE
100%
100%
100%
0%
0%
0%
Figure 52. Mux Configuration Example
MUX
Rev. 0 | Page 41 of 72
PWM
PWM
PWM
MIN
MIN
MIN
CONFIG
CONFIG
CONFIG
Example Mux Settings
[7:5] (BHVR), PWM1 Configuration Register (0x5C).
[7:5] (BHVR), PWM2 Configuration Register (0x5D).
[7:5] (BHVR), PWM3 Configuration Register (0x5E).
These settings configure the mux, as shown in Figure 52.
TACHOMETER 1
MEASUREMENT
TACHOMETER 2
MEASUREMENT
TACHOMETER 3
MEASUREMENT
PWM
PWM
PWM
GENERATOR
GENERATOR
GENERATOR
101 = Fastest speed calculated by local and Remote 2
temperature controls PWM1
000 = Remote 1 temperature controls PWM2
000 = Remote 1 temperature controls PWM3
AND 4
PWM
PWM
PWM
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
ADT7476A