ADT7473 Analog Devices, Inc., ADT7473 Datasheet - Page 7

• Manufacturer Part Number: ADT7473
• Description: Dbcool Remote Thermal Monitor And Fan Controller
• Manufacturer: Analog Devices, Inc.

PIN CONFIGURATION AND FUNCTION DESCRI
Table 4. Pin Function Descriptions
Pin No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Mnemonic
SCL
GND
V
TACH3
PWM2
SMBALERT
TACH1
TACH2
PWM3
TACH4
GPIO
THERM
SMBALERT
D2−
D2+
D1−
D1+
V
PWM1
XTO
SDA
CC
CCP
Description
Digital Input (Open Drain). SMBus serial clock input. Requires SMBus pull-up.
Ground Pin for the ADT7473.
Power Supply. Powered by 3.3 V.
Digital Input (Open Drain). Fan tachometer input to measure speed of Fan 3.
Digital Output (Open Drain). Requires 10 kΩ typical pull-up. Pulse-width modulate
Can be configured as a high or low frequenc
Digital Output (Open Drain). Can be reconfigured as an SMBALERT interrupt output to signal out-of-limit
conditions.
Digital Input (Open Drain). Fan tachometer input to measure speed of Fan 1.
Digital I put (Open Drain). Fan tachometer input to measure speed of Fan 2.
Digital I/O (Open Drain). Pulse-width modulated output to control the speed of Fan 3 and Fan 4. Requires 10 kΩ
typical pull-up. Can be configured as a high or low frequency drive.
Digital Input (Open Drain). Fan tachometer input to measure speed of Fan 4.
General-Purpose Open Drain Digital I/O.
Bidirectional THERM pin. Can be used to time and monitor assertions on the THERM input as well as to assert when
an ADT7473 THERM overtemperature limit is exceeded. For example, the pin can be connected to the PROCHOT
output of an Intel Pentium 4 processor or to the output of a trip point temperature sensor. Can be used as an
output to signal overtemperature conditions.
Digital Output (Open Drain). This pin can be reconfigured as an SMBALERT interrupt output to signal out-of-limit
conditions.
Cathode Connection to Second Thermal Diode.
Anode Connection to Second Thermal Diode.
Cathode Connection to First Thermal Diode.
Anode Connection to First Thermal Diode.
Analog Input. Monitors processor core v
Digital Output (Open Drain). Pulse-width modulated output to control Fan 1 speed. Requires 10 kΩ typical pull-up.
Also functions as the output from the XNOR tree in XNOR test mode.
Digital I/O (Open Drain). SMBus bidirectional serial data. Requires 10 kΩ typical pull-up.
n
PWM2/SMBALERT
TACH3
TACH1
TACH2
PWM3
GND
SCL
V
CC
1
2
3
4
5
6
7
8
(Not to Scale)
ADT7473
Figure 3. Pin Configuration
TOP VIEW
Rev. A | Page 7 of 76
oltage (0 V to 3 V).
16
15
14
13
12
11
10
9
y drive.
PTIONS
SDA
PWM1/XTO
D1+
D1–
D2+
TACH4/GPIO/THERM/SMBALERT
V
D2–
CCP
d output to c
ontrol Fan 2 speed.
ADT7473