Analog Devices dBCool ADT7476, Manual

Page: 67 / 72

ADT7476
Rev. B | Page 67 of 72
Table 47. Local Temperature Offset
Register Address Bit R/W
1
Description Power-On Default
0x71 [7:0] R/W Local temperature offset. 0x00
Allows a temperature offset to be applied automatically to the
local temperature measurement. Bit 1 of Configuration
Register 5 (0x7C) determines the range and resolution of this
register.
1 This register becomes read-only when the Configuration Register 1 LOCK bit is set to 1. Any subsequent attempts to write to this register fail.
Table 48. Remote 2 Temperature Offset
Register Address Bit R/W
1
Description Power-On Default
0x72 [7:0] R/W Remote 2 temperature offset. 0x00
Allows a temperature offset to be applied automatically to the Remote
2 temperature channel measurement. Bit 1 of Configuration Register 5
(0x7C) determines the range and resolution of this register.
1
This register becomes read-only when the Configuration Register 1 LOCK bit is set to 1. Any subsequent attempts to write to this register fail.
Table 49. Register 0x73—Configuration Register 2 (Power-On Default = 0x00)
Bit Name R/W 1 Description
[0] FanPresenceDT R/W When FanPresenceDT = 1, the state of Bits [3:1] of 0x73 reflects the presence of a 4-wire fan on
the appropriate TACH channel.
[1] Fan1Detect Read Fan1Detect = 1 indicates that a 4-wire fan is connected to the TACH1 input.
[2] Fan2Detect Read Fan2Detect = 1 indicates that a 4-wire fan is connected to the TACH2 input.
[3] Fan3Detect Read Fan3Detect = 1 indicates that a 4-wire fan is connected to the TACH3 input.
[4] AVG R/W AVG = 1, averaging on the temperature and voltage measurements is turned off. This allows
measurements on each channel to be made much faster (x16).
[5] ATTN R/W ATTN = 1, the ADT7476 removes the attenuators from the 2.5 V, V
CCP
, 5 V, and 12 V inputs. These
inputs can be used for other functions such as connecting up external sensors. It is also possible
to remove attenuators from individual channels using Bits [7:4] of Configuration Register 4
(0x7D).
[6] CONV R/W CONV = 1, the ADT7476 is put into a single-channel ADC conversion mode. In this mode, the
ADT7476 can be made to read continuously from one input only, for example, Remote 1
temperature. The appropriate ADC channel is selected by writing to Bits [7:5] of TACH 1
minimum high byte register (0x55).
Register 0x55, Bits [7:5]
000 2.5 V
001 V
CCP
010 V
CC
(3.3 V)
011 5 V
100 12 V
101 Remote 1 temperature
110 Local temperature
111 Remote 2 temperature
[7] Reserved This bit is reserved and should not be changed.
1 This register becomes read-only when the Configuration Register 1 LOCK bit is set to 1. Any subsequent attempts to write to this register fail.
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