ADT7468 Analog Devices, Inc., ADT7468 Datasheet - Page 11

• Manufacturer Part Number: ADT7468
• Description: Dbcool Remote Thermal Controller And Voltage Monitor
• Manufacturer: Analog Devices, Inc.

Bit 1 = 1 switches the fan drive to low frequency PWM,
programmable between 10 Hz and 100 Hz, the same as the
ADT7463. The default = 0 = HF PWM.
Bit 2 sets the direction for the GPIO: 0 = input, 1 = output.
Bit 3 sets the GPIO polarity: 0 = active low, 1 = active high.
Setting the Functionality of Pin 14
Pin 14 on the ADT7468 has four possible functions:
SMBALERT , THERM , GPIO, and TACH4. The user chooses
the required functionality by setting Bit 0 and Bit 1 of
Configuration Register 4 at Address 0x7D.
Table 4. Pin 14 Settings
Bit 0
0
0
1
1
Bit 1
0
1
0
1
Function
TACH4
THERM
SMBALERT
GPIO
FRONT
CHASSIS
FAN
REAR
CHASSIS
FAN
AMBIENT
TEMPERATURE
CONTROLLER
ADP316x
VRM
V
COMP
Figure 15. ADT7468 Configuration
TACH2
PWM3
TACH3
D1+
D1–
3.3VSB
5V
12V/VID5
CURRENT
V
Rev. A | Page 11 of 84
CORE
ADT7468
VID[0:4]/VID[0:5]
GND
SMBALERT
THERM
RECOMMENDED IMPLEMENTATION
Configuring the ADT7468 as in Figure 15 allows the system
designer to use the following features:
•
•
•
•
•
•
TACH1
PWM1
SDA
SCL
D2+
D2–
Two PWM outputs for fan control of up to three fans (the
front and rear chassis fans are connected in parallel).
Three TACH fan speed measurement inputs.
V
CPU temperature measured using Remote 1 temperature
channel.
Ambient temperature measured through Remote 2
temperature channel.
Bidirectional THERM pin. This feature allows Intel
Pentium 4 PROCHOT monitoring and can function as an
overtemperature THERM output. Alternatively, it can be
programmed as an SMBALERT system interrupt output.
CC
5(VRM9)/6(VRM10)
measured internally through Pin 3.
PROCHOT
CPU FAN
CPU
ICH
ADT7468