ADT7467 Analog Devices, Inc., ADT7467 Datasheet - Page 69

• Manufacturer Part Number: ADT7467
• Description: Dbcool Remote Thermal Monitor And Fan Controller
• Manufacturer: Analog Devices, Inc.

Table 35. Register 0x62—Enhanced Acoustics Register 1 (Power-On Default = 0x00)
Bit
<2:0>
<3>
<4>
<5>
<6>
<7>
1
This register becomes a read-only register when the Configuration Register 1 lock bit is set to 1. Any subsequent attempts to write to this register fail.
Name
ACOU
EN1
SYNC
MIN1
MIN2
MIN3
R/W
Read/write
Read/write
Read/write
Read/write
Read/write
Read/write
1
Description
These bits select the ramp rate applied to the PWM1 output. Instead of PWM1 jumping instantaneously to
its newly calculated speed, PWM1 ramps gracefully at the rate determined by these bits. This feature
enhances the acoustics of the fan being driven by the PWM1 output.
Time Slot Increase
000 = 1
001 = 2
010 = 3
011 = 4
100 = 8
101 = 12
110 = 24
111 = 48
When this bit is 1, acoustic enhancement is enabled on PWM1 output.
SYNC = 1 synchronizes fan speed measurements on TACH2, TACH3, and TACH4 to PWM3. This allows up to
three fans to be driven from PWM3 output and their speeds to be measured.
SYNC = 0 synchronizes only TACH3 and TACH4 to PWM3 output.
When the ADT7467 is in automatic fan control mode, this bit defines whether PWM1 is off (0% duty cycle) or
at PWM1 minimum duty cycle when the controlling temperature is below its T
0 = 0% duty cycle below T
1 = PWM1 minimum duty cycle below T
When the ADT7467 is in automatic fan speed control mode and the controlling temperature is below its
T
0 = 0% duty cycle below T
1 = PWM 2 minimum duty cycle below T
When the ADT7467 is in automatic fan speed control mode, this bit defines whether PWM3 is off (0% duty
cycle) or at PWM3 minimum duty cycle when the controlling temperature is below its T
value.
0 = 0% duty cycle below T
1 = PWM3 minimum duty cycle below T
MIN
– hysteresis value, this bit defines whether PWM2 is off (0% duty cycle) or at PWM2 minimum duty cycle.
MIN
MIN
MIN
Time for 33% to 100%
35 sec
17.6 sec
11.8 sec
7 sec
4.4 sec
3 sec
1.6 sec
0.8 sec
– hysteresis.
– hysteresis.
– hysteresis.
Rev. A | Page 69 of 80
MIN
MIN
MIN
– hysteresis.
– hysteresis.
– hysteresis.
MIN
– hysteresis value.
MIN
– hysteresis
ADT7467