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ADM1029

Register 80h, 81h, 82h – Temp x

Bit

Name

R/W

Description

<7:0>

Temp x

R/W

This register contains the minimum temperature value for automatic fan speed

control based on the Temp x

* temperature. On power-up Pin 18 is sampled

by the ADC to determine the default value for Temp x

Speed Control is disabled. There are eight strappable options on Pin 18.

These options are used to set Temp x

Register (Reg 01h, Bit 0). The options are as follows:

ADC MSBs

R1

R2

Install

Temp x

111

0

∞

1

Disabled

101

18 kΩ

82 kΩ

1

48°C

110

22 kΩ

47 kΩ

1

40°C

100

12 kΩ

15 kΩ

1

32°C

011

15 kΩ

12 kΩ

0

32°C

010

47 kΩ

22 kΩ

0

40°C

001

82 kΩ

18 kΩ

0

48°C

000

∞

0

0

Disabled

*“x” denotes the number of the temperature channel. Register 80h is for the Local temperature channel, 81h is for Remote 1 Temp (D1), 82h is for Remote 2

Temp (D2).

Register 88h, 89h, 8Ah Temp x

Bit

Name

R/W

Description

<3:0>

Temp x

R/W

This nibble contains the temperature range over which automatic fan speed

control operates based on the Temp x

* measured temperature. Only a limited

number of temperature ranges are supported as follows:

Bits <3:0>

0000

5°C

0001

10°C

0010

20°C

0011

40°C

0100

80°C

<7:4>

Temp x

R/W

This nibble allows programmability of the Hysteresis level around the temperature

at which the fan being controlled by Temp x

* will switch on in automatic fan

speed control mode. Values from 0°C to 15°C are possible. If a value other than

0°C is programmed as a Hysteresis value, the fan will switch on when Temp x*

pulsewidth in the Fan x

* Speed 1 register.

*“x” denotes the number of the temperature channel. Register 88h is for the Local temperature channel , 89h is for Remote 1 Temp (D1), 8Ah is for Remote 2 Temp (D2).