ADT7463ARQZ ON Semiconductor, ADT7463ARQZ Datasheet - Page 19

• Manufacturer Part Number: ADT7463ARQZ
• Description: IC REMOTE THERMAL CTRLR 24-QSOP
• Manufacturer: ON Semiconductor
• Series: dBCool®r

Specifications of ADT7463ARQZ

• Function: Fan Control, Temp Monitor
• Topology: ADC, Comparator, Fan Speed Counter, Multiplexer, Register Bank
• Sensor Type: External & Internal
• Sensing Temperature: -40°C ~ 120°C, External Sensor
• Output Type: SMBus™
• Output Alarm: No
• Output Fan: Yes
• Voltage - Supply: 3 V ~ 5.5 V
• Operating Temperature: -40°C ~ 120°C
• Mounting Type: Surface Mount
• Package / Case: 24-QSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

LIMITS, STATUS REGISTERS, AND INTERRUPTS
Limit Values
Associated with each measurement channel on the ADT7463
are high and low limits. These can form the basis of system
status monitoring: a status bit can be set for any out-of-limit
condition and detected by polling the device. Alternatively,
SMBALERT interrupts can be generated to flag a processor or
microcontroller of out-of-limit conditions.
8-Bit Limits
The following is a list of 8-bit limits on the ADT7463.
Voltage Limit Registers
Reg. 0x44 2.5 V Low Limit = 0x00 Default
Reg. 0x45 2.5 V High Limit = 0xFF Default
Reg. 0x46 V
Reg. 0x47 V
Reg. 0x48 V
Reg. 0x49 V
Reg. 0x4A 5 V Low Limit = 0x00 Default
Reg. 0x4B 5 V High Limit = 0xFF Default
Reg. 0x4C 12 V Low Limit = 0x00 Default
Reg. 0x4D 12 V High Limit = 0xFF Default
Temperature Limit Registers
Reg. 0x4E Remote 1 Temp Low Limit = 0x81 Default
Reg. 0x4F Remote 1 Temp High Limit = 0x7F Default
Reg. 0x6A Remote 1 THERM
Reg. 0x50 Local Temp Low Limit = 0x81 Default
Reg. 0x51 Local Temp High Limit = 0x7F Default
Reg. 0x6B Local THERM
Reg. 0x52 Remote 2 Temp Low Limit = 0x81 Default
Reg. 0x53 Remote 2 Temp High Limit = 0x7F Default
Reg. 0x6C Remote 2 THERM
THERM Limit Register
Reg. 0x7A THERM
16-Bit Limits
The fan TACH measurements are 16-bit results. The fan TACH
limits are also 16 bits, consisting of a high byte and low byte.
Since fans running under speed or stalled are normally the only
conditions of interest, only high limits exist for fan TACHs. Since
fan TACH period is actually being measured, exceeding the limit
indicates a slow or stalled fan.
REV. C
THERM
THERM
THERM Limit = 0x00 Default
THERM
CCP
CCP
CC
CC
Low Limit = 0x00 Default
High Limit = 0xFF Default
Low Limit = 0x00 Default
High Limit = 0xFF Default
THERM
THERM
THERM Limit = 0x64 Default
THERM
THERM
THERM
THERM Limit = 0x64 Default
THERM
THERM
THERM
THERM
THERM Limit = 0x64 Default
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Fan Limit Registers
Reg. 0x54 TACH1 Minimum Low Byte = 0xFF Default
Reg. 0x55 TACH1 Minimum High Byte = 0xFF Default
Reg. 0x56 TACH2 Minimum Low Byte = 0xFF Default
Reg. 0x57 TACH2 Minimum High Byte = 0xFF Default
Reg. 0x58 TACH3 Minimum Low Byte = 0xFF Default
Reg. 0x59 TACH3 Minimum High Byte = 0xFF Default
Reg. 0x5A TACH4 Minimum Low Byte = 0xFF Default
Reg. 0x5B TACH4 Minimum High Byte = 0xFF Default
Out-of-Limit Comparisons
Once all limits are programmed, the ADT7463 can be enabled
for monitoring. The ADT7463 measures all parameters in
round-robin format and sets the appropriate status bit for out-
of-limit conditions. Comparisons are done differently depending
on whether the measured value is being compared to a high or
low limit.
HIGH LIMIT: > COMPARISON PERFORMED
LOW LIMIT: < OR = COMPARISON PERFORMED
Figure 17. Temperature > Low Limit: No INT
ADT7463
NO INT
LOW LIMIT
LOW LIMIT
TEMP >