REV. C

–44–

ADT7463

Table XXII. Register 0x63 – Enhance Acoustics Reg 2 (Power-On Default = 0x00)

Bit

Name

R/W*

Description

<2:0>

ACOU3

Read/Write

These bits select the ramp rate applied to the PWM3 output. Instead of PWM3 jump-

ing instantaneously to its newly calculated speed, PWM3 ramps gracefully at the rate

determined by these bits. This effect enhances the acoustics of the fan being driven by the

PWM3 output.

Time Slot Increase

Time for 33% to 100%

000 = 1

35 s

001 = 2

17.6 s

010 = 3

11.8 s

011 = 5

7 s

100 = 8

4.4 s

101 = 12

3 s

110 = 24

1.6 s

111 = 48

0.8 s

<3>

EN3

Read/Write

When this bit is 1, acoustic enhancement is enabled on PWM3 output.

<6:4>

ACOU2

Read/Write

These bits select the ramp rate applied to the PWM2 output. Instead of PWM2

jumping instantaneously to its newly calculated speed, PWM2 ramps gracefully at the

rate determined by these bits. This effect enhances the acoustics of the fans being driven

by the PWM2 output.

Time Slot Increase

Time for 33% to 100%

000 = 1

35 s

001 = 2

17.6 s

010 = 3

11.8 s

011 = 5

7 s

100 = 8

4.4 s

101 = 12

3 s

110 = 24

1.6 s

111 = 48

0.8 s

<7>

EN2

Read/Write

When this bit is 1, acoustic enhancement is enabled on PWM2 output.

*This register becomes read-only when the Configuration Register 1 Lock bit is set to 1. Any further attempts to write to this register will have no effect.

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