ADT7490_15 Datasheet, PDF (7/76 Pages) Analog Devices – dBCool Remote Thermal Monitor and Fan Controller with PECI Interface

ADT7490
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
SDA 1
24 PWM1/XTO
SCL 2
GND 3
V_CC 4
GPIO1 5
GPIO2 6
PECI 7
23 V_CCP
22 +2.5V_IN/THERM
21 +12V_IN
ADT7490
TOP VIEW
(Not to Scale)
20 +5V_IN
19 I_MON
18 D1+
V_TT 8
TACH3 9
17 D1–
16 D2+
PWM2/SMBALERT 10
15 D2–
TACH1 11
TACH2 12
14 _{TACH4/THERM/SMBALERT/ADDR SELECT}
13 PWM3/ADDREN
Figure 3.Pin Configuration
Table 4. Pin Function Descriptions
Pin No. Mnemonic
Type
1
SDA
Digital I/O
2
SCL
Digital Input
3
GND
Ground
4
VCC
Power Supply
5
GPIO1
Digital Input/Output
6
GPIO2
Digital Input/Output
7
PECI
Digital Input
8
VTT
Analog Input
9
TACH3
10
PWM2/
Digital Input
Digital Output
SMBALERT
11
TACH1
12
TACH2
13
PWM3/
Digital Input
Digital Input
Digital Output
ADDREN
14
TACH4/
THERM/
Digital Input/Output
SMBALERT/
ADDR SELECT
15
D2−
Analog Input
16
D2+
Analog Input
17
D1−
Analog Input
18
D1+
Analog Input
19
IMON
Analog Input
Description
SMBus Bidirectional Serial Data. Open drain, requires SMBus pull-up.
SMBus Serial Clock Input. Open drain, requires SMBus pull-up.
Ground Pin.
3.3 V ± 10%.
General-Purpose Open-Drain Digital Input/Output. Frequently used for switching
loadline resistors into VR loadline circuitry or for switching LEDs using external FETs.
General-Purpose Open-Drain Digital Input/Output. Frequently used for switching
loadline resistors into VR loadline circuitry or for switching LEDs using external FETs.
PECI Input to Report CPU Thermal Information. PECI voltage level is referenced on the
VTT input
Voltage Reference for PECI. This is the supply voltage for the PECI interface and must be
present to measure temperature over the PECI interface. This voltage is also monitored
and presented in register 0x1E.
Fan Tachometer Input to Measure Speed of FAN 3 (Open-Drain Digital Input).
Pulse Width Modulated Output to Control FAN 2 Speed. Open drain requires 10 kΩ
typical pull-up.
Digital Output (Open Drain). This pin can be reconfigured as an SMBALERT interrupt
output to signal out-of-limit conditions.
Fan Tachometer Input to Measure Speed Of Fan 1 (Open-Drain Digital Input.).
Fan Tachometer Input To Measure Speed Of Fan 2 (Open-Drain Digital Input.).
Pulse Width Modulated Output to Control Fan 3 Speed. Open drain requires 10kΩ
typical pull-up.
If pulled low on power-up, the ADT7490 enters address select mode, and the state of
Pin 14 (ADDR SELECT) determines the ADT7490’s slave address.
Fan Tachometer Input to Measure Speed of Fan 4 (Open-Drain Digital Input).
May be reconfigured as a bidirectional THERM pin. Can be connected to PROCHOT
output of processor, to time and monitor PROCHOT assertions. Can be used as an
output to signal overtemperature conditions or for clock modulation purposes.
Active Low Digital Output. The SMBALERT Pin is used to signal out-of-limit comparisons
of temperature, voltage, and fan speed. This is compatible with SMBus alert.
Can also be used at device power-up to assign SMBus address.
Negative Connection for Remote Temperature Sensor 2.
Positive Connection to Remote Temperature Sensor 2.
Negative Connection for Remote Temperature Sensor 1.
Positive Connection to Remote Temperature Sensor 1.
Monitors Current Output of Analog Devices ADP319x family of VRD10/VRD11
controllers.
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