EVAL-ADT7467EBZ ON Semiconductor, EVAL-ADT7467EBZ Datasheet - Page 50

• Manufacturer Part Number: EVAL-ADT7467EBZ
• Description: BOARD EVALUATION FOR ADT7467
• Manufacturer: ON Semiconductor
• Series: dBCool®r

Specifications of EVAL-ADT7467EBZ

• Sensor Type: Temperature
• Sensing Range: -40°C ~ 120°C
• Interface: SMBus (2-Wire/I²C)
• Sensitivity: ±1.5°C
• Voltage - Supply: 3 V ~ 5.5 V
• Embedded: No
• Utilized Ic / Part: ADT7467
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

ADT7467
Enhanced Acoustics Register 1 (0x62)
Bit 7 (MIN3) = 0, PWM3 is off (0% PWM duty cycle) when the
temperature is below T
Bit 7 (MIN3) = 1, PWM3 runs at PWM3 minimum duty cycle
below T
Bit 6 (MIN2) = 0, PWM2 is off (0% PWM duty cycle) when the
temperature is below T
Bit 6 (MIN2) = 1, PWM2 runs at PWM2 minimum duty cycle
below T
Bit 5 (MIN1) = 0, PWM1 is off (0% PWM duty cycle) when the
temperature is below T
Bit 5 (MIN1) = 1, PWM1 runs at PWM1 minimum duty cycle
below T
STEP 9: OPERATING POINTS FOR
TEMPERATURE CHANNELS
The operating point for each temperature channel is the
optimal temperature for that thermal zone. The hotter each
zone is allowed to be, the more quiet the system, because the
fans are not required to run as fast. The ADT7467 increases or
decreases fan speeds as necessary to maintain the operating
point temperature, allowing for system-to-system variations
MIN
MIN
MIN
− T
− T
− T
AMBIENT TEMP
HYST
HYST
HYST
REMOTE 2 =
REMOTE 1 =
VRM TEMP
CPU TEMP
.
.
.
LOCAL =
MIN
MIN
MIN
− T
− T
− T
THERMAL CALIBRATION
THERMAL CALIBRATION
THERMAL CALIBRATION
HYST
HYST
HYST
T
T
T
Figure 69. Operating Point Value Dynamically Adjusts Automatic Fan Control Settings
MIN
MIN
MIN
.
.
.
T
T
T
RANGE
RANGE
RANGE
100%
100%
100%
0%
0%
0%
Rev. 3 | Page 50 of 77 | www.onsemi.com
MUX
OPERATING
POINT
PWM
PWM
PWM
MIN
MIN
MIN
and eliminating the need to design for the worst case. If a
sensible operating point value is chosen, any T
selected in the system characterization. If the T
low, the fans run sooner than required and the temperature is
below the operating point. In response, the ADT7467 increases
T
zone to approach the operating point. Likewise, too high a T
value causes the operating point to be exceeded, and, in turn,
the ADT7467 reduces T
the system.
Programming Operating Point Registers
There are three operating point registers, one for each tempera-
ture channel. These 8-bit registers allow the operating point
temperatures to be programmed with 1°C resolution.
Operating Point Registers
Register 0x33, Remote 1 operating point = 0xA4 (100°C default)
Register 0x34, local temperature operating point = 0xA4 (100°C
default)
Register 0x35, Remote 2 operating point = 0xA4 (100°C default)
MIN
ENHANCEMENT)
ENHANCEMENT)
ENHANCEMENT)
to keep the fans off longer and to allow the temperature
TACHOMETER 1
MEASUREMENT
TACHOMETER 2
MEASUREMENT
TACHOMETER 3
MEASUREMENT
(ACOUSTIC
(ACOUSTIC
(ACOUSTIC
CONTROL
CONTROL
CONTROL
RAMP
RAMP
RAMP
AND 4
GENERATOR
GENERATOR
GENERATOR
CONFIG
CONFIG
CONFIG
MIN
PWM
PWM
PWM
PWM
PWM
PWM
to turn the fans on sooner to cool
PWM1
TACH1
PWM2
TACH2
PWM3
TACH3
FRONT CHASSIS
REAR CHASSIS
CPU FAN SINK
MIN
MIN
value can be
value is too
MIN