ADT7470 Analog Devices, Inc., ADT7470 Datasheet - Page 6

• Manufacturer Part Number: ADT7470
• Description: Temperature Sensor Hub And Fan Controller
• Manufacturer: Analog Devices, Inc.

ADT7470
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
Table 3. Pin Function Descriptions
Pin No.
1
2
3
4
5
6
7
8
9
10
11
12
13
13
14
15
16
Mnemonic
SCL
GND
V
TACH3
PWM2
TACH1
TACH2
PWM3
TACH4
PWM4
ADDR
TMP_IN
FULL_SPEED
TMP_START
SMBALERT
PWM1
SDA
CC
Description
Digital Input (Open Drain). SMBus serial clock input. Requires SMBus pull-up.
Ground Pin.
Power Supply Pin. Can be powered by 3.3 V standby if operation in low power states is required.
Digital Input (Open Drain). Fan tachometer input to measure the speed of Fan 3.
Digital I/O (Open Drain). Requires 10 kΩ typical pull-up. Pulse-width modulated output to control
the speed of Fan 2. Can be configured as GPIO by setting Bit 0x7F<2> = 1.
Digital Input (Open Drain). Fan tachometer input to measure the speed of Fan 1.
Digital Input (Open Drain). Fan tachometer input to measure the speed of Fan 2.
Digital I/O (Open Drain). Pulse-width modulated output to control the speed of Fan 3.
Requires 10 kΩ typical pull-up. Can be configured as GPIO by setting Bit 0x7F<1> = 1.
Digital Input (Open Drain). Fan tachometer input to measure the speed of Fan 4.
Digital I/O (Open Drain). Pulse-width modulated output to control the speed of Fan 4.
Requires 10 kΩ typical pull-up. Can be configured as GPIO by setting Bit 0x7F<0> = 1.
Three-state Input. Used to set the SMBus device address.
Digital Input (Open Drain). PWM input to PWM processing engine that interprets daisy-chained output
from multiple TMP05 temperature sensors. Readings from individual TMP05 temperature sensors are
available by reading the temperature reading registers over the SMBus.
Digital Input Active Low (Open Drain). This input blasts the fans to PWMMAX when the pin is pulled low
externally.
Digital Output (Open Drain). This pin can be used as an output to start daisy-chained temperature
measurements from TMP05 or TMP06 temperature sensors.
Digital Output Active Low (Open Drain). This pin can be reconfigured as an SMBALERT interrupt output
to signal out-of-limit conditions such as fan failures.
Digital I/O (Open Drain). Pulse-width modulated output to control the speed of Fan 1.
Requires 10 kΩ typical pull-up. Can be configured as GPIO by setting Bit 0x7F<3> = 1.
Digital I/O (Open Drain). SMBus bidirectional serial data. Requires SMBus pull-up.
TACH3
TACH1
TACH2
PWM2
PWM3
GND
SCL
V
CC
1
2
3
4
5
6
7
8
(Not to Scale)
ADT7470
TOP VIEW
Figure 3. Pin Configuration
Rev. B | Page 6 of 40
15
14
13
12
11
10
16
9
SDA
PWM1
SMBALERT
FULL_SPEED/TMP_START
TMP_IN
ADDR
PWM4
TACH4