ASC7611 ETC2 [List of Unclassifed Manufacturers], ASC7611 Datasheet - Page 15

• Manufacturer Part Number: ASC7611
• Description: HARDWARE MONITOR WITH INTEGRATED FAN CONTROL
• Manufacturer: ETC2 [List of Unclassifed Manufacturers]

Temperature Measurement
Temperatures are measured with a precision Delta-V
sigma-delta converter. The user may set limits on these readings to be continuously monitored and alarm bits set when they
are exceeded. Separately, the measurements are also delivered to the automatic fan control system to adjust fan speed. The
following registers contain the readings from the internal and remote sensors.
Registers 25-10h, 26-15h and 27-0Eh: Zone Temperature Readings (10-Bit, 2’s Complement Reporting)
The Zone Temperature registers reflect the current temperature of the internal and remote diodes. Processor (Zone 1)
Temp register reports the temperature measured by the thermal diode connected to the Remote 1- and Remote 1+ pins.
Internal (Zone 2) Temp register reports the temperature measured by the internal (junction) temperature sensor. Remote 2
(Zone 3) Temp register reports the temperature measured by the thermal diode connected to the second set of Remote 2-
and Remote 2+ pins. Temperatures are represented as 10 bit, 2’s complement, signed numbers, in degrees Celsius, as
shown below in Table 1.
The Temperature Reading register will return a value of 8000h if the remote diode pins are not used by the board designer or
are not functioning properly. This reading will cause the zone limit bits (bits 4 and 6) in the Interrupt Status Register (41h)
and the remote diode fault status bit (bits 6 and 7) in the Interrupt Status Register 2 (42h) to be set. These registers are read-
only – a write to these registers has no effect.
© Andigilog, Inc. 2006
Register
Address
0Eh
25h
10h
26h
15h
27h
Table 1 Relationship between Temperature and 2’s Complement Digital Output, -55°C to +125°C
Read/
Write
R
R
R
R
R
R
Zone 1 Temper-
ature (MS Byte)
Zone 1 Temper-
ature (LS Byte)
Zone 2 Temper-
ature (MS Byte)
Zone 2 Temper-
ature (LS Byte)
Zone 3 Temper-
ature (MS Byte)
Zone 3 Temper-
ature (LS Byte)
Register Name
Temperature
+1.75°C
+0.25°C
+125°C
+100°C
-1.75°C
+50°C
+25°C
+10°C
-55°C
0°C
(MSB)
Bit 7
9
1
9
1
9
1
Bit 6
BE
8
0
8
0
8
0
www.andigilog.com
Digital Output (2’s Complement)
0111
0110
0011
0001
0000
0000
0000
0000
1111
1100
methodology converted to a digital temperature reading by a 10-bit
10-Bit Resolution
High Byte
- 15 -
Bit 5
X
X
X
7
7
7
1101
0100
0010
1001
1010
0001
0000
0000
1110
1001
Bit 4
X
X
X
6
6
6
00
00
00
00
00
11
01
00
01
00
Low Byte
XX
XX
XX
XX
XX
XX
XX
XX
XX
XX
Bit 3
Ignore
X
X
X
5
5
5
XXXX
XXXX
XXXX
XXXX
XXXX
XXXX
XXXX
XXXX
XXXX
XXXX
Bit 2
X
X
X
4
4
4
October 2006 - 70A05007
Bit 1
X
X
X
3
3
3
aSC7611
(LSB)
Bit 0
X
X
X
2
2
2
Default
Value
00
00
00
00
00
00