ADT7470 Analog Devices, Inc., ADT7470 Datasheet - Page 31

• Manufacturer Part Number: ADT7470
• Description: Temperature Sensor Hub And Fan Controller
• Manufacturer: Analog Devices, Inc.

Exceeding any of the tach min limit registers shown in Table 35 by 1 indicates that the fan is running too slowly or has stalled.
The appropriate status bit is set in Interrupt Status Register 2 to indicate the fan failure.
Exceeding any of the tach max limit registers by 1 indicates that the fan is too fast. The appropriate status bit is set in Interrupt Status
Register 2 to indicate the fan failure.
Table 35. Register 0x58 to Register 0x67. Fan Tachometer Limit Registers
Register Address
0x58
0x59
0x5A
0x5B
0x5C
0x5D
0x5E
0x5F
0x60
0x61
0x62
0x63
0x64
0x65
0x66
0x67
Table 36. Register 0x68. PWM1/PWM2 Configuration Register (Power-On Default = 0x00)
Bit Name
<0>
<1>
<2>
<3>
<4> INV2
<5> INV1
<6> BHVR2
<7> BHVR1
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
Read/Write
N/A
N/A
N/A
N/A
Read/Write
Read/Write
Read/Write
Read/Write
Description
Tach 1 Min Low Byte
Tach 1 Min High Byte
Tach 2 Min Low Byte
Tach 2 Min High Byte
Tach 3 Min Low Byte
Tach 3 Min High Byte
Tach 4 Min Low Byte
Tach 4 Min High Byte
Tach 1 Max Low Byte
Tach 1 Max High Byte
Tach 2 Max Low Byte
Tach 2 Max High Byte
Tach 3 Max Low Byte
Tach 3 Max High Byte
Tach 4 Max Low Byte
Tach 4 Max High Byte
Description
Set to 0 (default).
Set to 0 (default).
Set to 0 (default).
Set to 0 (default).
Setting this bit to 1 inverts the PWM2 output (PWMMAX = logic low).
Default = 0 drives the PWM2 output logic high for PWMMAX duty cycle.
Setting this bit to 1 inverts the PWM1 output (PWMMAX = logic low).
Default = 0 drives the PWM1 output logic high for PWMMAX duty cycle.
This bit assigns fan behavior for PWM2 output.
0 = manual fan control mode (PWM duty cycle controlled in software).
1 = fastest speed calculated by all temperatures control PWM2 (automatic fan control mode).
This bit assigns fan behavior for PWM1 output.
0 = manual fan control mode (PWM duty cycle controlled in software).
1 = fastest speed calculated by all temperatures control PWM1 (automatic fan control mode).
Rev. B | Page 31 of 40
Power-On Default
0xFF
0xFF
0xFF
0xFF
0xFF
0xFF
0xFF
0xFF
0x00
0x00
0x00
0x00
0x00
0x00
0x00
0x00
ADT7470