ADT7460ARQZ-RL7 ONSEMI [ON Semiconductor], ADT7460ARQZ-RL7 Datasheet - Page 41

• Manufacturer Part Number: ADT7460ARQZ-RL7
• Description: dBCOOL Remote Thermal Monitor and Fan Controller
• Manufacturer: ONSEMI [ON Semiconductor]

1. This register becomes read−only when the Configuration Register 1 lock bit is set to 1. Further attempts to write to this register have no effect.
2. If any temperature measured exceeds its THERM limit, all PWM outputs drive their fans at 100% duty cycle. This is a fail−safe mechanism
1. This register becomes read−only when the Configuration Register 1 lock bit is set to 1. Further attempts to write to this register have no effect.
2. Each 4−bit value controls the amount of temperature hysteresis applied to a particular temperature channel. Once the temperature for that
1. This register becomes read−only when the Configuration Register 1 lock bit is set to 1. Further attempts to write to this register have no effect.
1. This register becomes read−only when the Configuration Register 1 lock bit is set to 1. Further attempts to write to this register have no effect.
1. This register becomes read−only when the Configuration Register 1 lock bit is set to 1. Further attempts to write to this register have no effect.
Table 61. THERM Limit Registers
Table 62. Temperature Hysteresis Registers
Table 63. XNOR Tree Test Enable Register (Power−On Default = 0x00)
Table 64. Remote 1 Temperature Offset Register (Power−On Default = 0x00)
Table 65. Local Temperature Offset Register (Power−On Default = 0x00)
Register Address
Register Address
Register Address
Register Address
Register Address
incorporated to cool the system in the event of a critical overtemperature. It also ensures some level of cooling in the event that software
or hardware locks up. If set to 0x80, this feature is disabled. The PWM output remains at 100% until the temperature drops below THERM
Limit – Hysteresis. If the THERM pin is programmed as an output, exceeding these limits by 0.25°C can cause the THERM pin to assert
low as an output.
channel falls below its T
of hysteresis may be assigned to any temperature channel. The hysteresis value chosen also applies to that temperature channel if its
THERM limit is exceeded. The PWM output being controlled goes to 100% if the THERM limit is exceeded and remains at 100% until the
temperature drops below THERM – Hysteresis. For acoustic reasons, it is recommended that the hysteresis value not be programmed less
than 4°C. Setting the hysteresis value lower than 4°C causes the fan to switch on and off regularly when the temperature is close to T
<7:0>
<7:0>
0x6A
0x6B
0x6C
0x6D
0x6E
0x6F
0x70
0x71
MIN
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
value, the fan remains running at PWM
(Note 1)
Remote 1 THERM Limit
Local THERM Limit
Remote 2 THERM Limit
Remote 1 Local Temperature Hysteresis
Remote 2 Temperature Hysteresis
XNOR Tree Test Enable
<7:1>
Remote 1 Temperature Offset
Allows a twos complement offset value to be automatically added to or subtracted from the
Remote 1 temperature reading. This is to compensate for any inherent system offsets such as
PCB trace resistance. LSB value = 0.25°C.
Local Temperature Offset
Allows a twos complement offset value to be automatically added to or subtracted from the
local temperature reading. LSB value = 0.25°C.
<0>
Bit
Mnemonic
(Note 1)
XEN
RES
http://onsemi.com
Description (Note 2)
Description (Note 2)
ADT7460
If the XEN bit is set to 1, the device enters the XNOR tree test mode.
Clearing the bit removes the device from the XNOR test mode.
Unused. Do not write to these bits.
41
MIN
duty cycle until the temperature = T
Description
Description
Description
(Note 1)
(Note 1)
(Note 1)
Description
MIN
Power−On Default
Power−On Default
– Hysteresis. Up to 15°C
0x64 (100°C)
0x64 (100°C)
0x64 (100°C)
0x44
0x40
MIN.