ASC7512 ETC2 [List of Unclassifed Manufacturers], ASC7512 Datasheet - Page 21

• Manufacturer Part Number: ASC7512
• Description: DIGITAL TEMPERATURE SENSOR WITH INTEGRATED FAN CONTROL
• Manufacturer: ETC2 [List of Unclassifed Manufacturers]

Register
Address
Register 5F-60h: Auto Fan Speed Range, PWM Frequency
In Auto Fan Mode, when the temperature for a zone is above the Temperature Limit (Registers 67-69h) and below its
Absolute Temperature Limit (Registers 6A-6Bh), the speed of a fan assigned to that zone is determined as follows:
When the temperature reaches the Fan Temp Limit for a zone, the PWM output assigned to that zone will be Fan PWM
Minimum. Between Fan Temp Limit and (Fan Temp Limit + Range), the PWM duty cycle will increase linearly according to
the temperature as shown in the figure below. The PWM duty cycle will be 100% at (Fan Temp Limit + Range).
PWM frequency - FRQ[3:0] and HLFRQ
The PWM frequency bits [3:0] determine the PWM frequency for the fan. The aSC7512 has high and low frequency ranges
for the PWM outputs that are controlled by the HLFRQ bit.
PWM Frequency Selection (Default = 0011 = 30.04 Hz).
© Andigilog, Inc. 2006
5Fh
60h
Read/
Write
R/W
R/W
Zone 1 Range
Fan1 Frequency
Zone 2 Range
Register Name
Table 9 Register Setting vs PWM Frequency
(MSB)
RAN3
RAN3
Bit 7
HLFRQ
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
RAN[3:0]
RAN2
RAN2
Bit 6
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
FRQ [2:0]
www.andigilog.com
000
001
010
011
100
101
110
111
000
001
010
011
100
101
110
111
RAN1
RAN1
Bit 5
- 21 -
RAN0
RAN0
Bit 4
Linear Control
10.01 Hz
15.02 Hz
23.14 Hz
30.04 Hz (Default)
38.16 Hz
47.06 Hz
61.38 Hz
94.12 Hz
22.5 kHz
24 kHz
25.7 kHz
25.7 kHz
27.7 kHz
27.7 kHz
30 kHz
30 kHz
Range (°C)
Frequency
13.33
3.33
6.67
2.5
HLFRQ
10
16
PWM
2
4
5
8
Bit 3
RES
FRQ2
Bit 2
RES
FRQ1
Bit 1
RES
August 2006 - 70A05003
(LSB)
FRQ0
Bit 0
RES
aSC7512
Default
Value
C3
C3
Lock
X
X