
Product Description 
- 1 - 
 Andigilog, Inc. 2006 
www.andigilog.com 
December 2006 - 70A05012 
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OW
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OLTAGE 
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IGITAL 
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EMPERATURE 
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ENSOR
AND OLTAGE 
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ONITOR
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RODUCT 
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PECIFICATION
aSC7531A / aSC7531B 
The aSC7531 is a high-precision CMOS temperature sensor 
and voltage monitor with Simple Serial Transport (SST) 
compatible serial digital interface, intended for use in PC 
hardware monitor applications.  
Communication of device capabilities, temperature and voltage 
readings take place over the high-speed bi-directional SST 
interface. 
The SST temperature sensor provides a means for an analog 
signal to travel over a digital bus enabling remote temperature 
sensing in areas previously not monitored in the PC. The 
temperature sensor supports an internal and external thermal 
diode. aSC7531A is used with 2N3904 transistor connected as 
a remote diode, aSC7531B is used with CPU substrate diode. 
The aSC7531 is available in MSOP-10 surface mount 
package. 
Features 
On-chip and remote temperature sensors 
Accuracy: 
o
+/- 3°C over operational range 
o
Internal +/- 2°C over 40°C to 70°C 
o
Remote +/- 1°C over 50°C to 70°C 
Operational Range: -40°C to 125°C 
Temperature resolution: 0.125°C 
Voltage monitoring of 12V, 5V, 3.3V, 2.5V and Vccp 
to +/- 2% accuracy, 7.8mV resolution 
1-wire SST serial interface 
Negotiable SST signaling rate up to 2-Mbps 
Internally corrected for diode non-ideality and series 
resistance 
3-state address pin sets one of 3 SST bus address 
0x48 through 0x4A 
10-lead MSOP package 
 MSL-1 per JEDEC J-STD-020C 
Pb-free Matte Sn lead finish & RoHS Compliant 
Packages 
Ordering Information 
Pin Configuration 
GND
SST
1 
2 
3 
4 
D- 
9 
ADD0
V
DD
D+ 
2.5V
8 
Applications 
Desktop and Notebook Computers 
Application Diagram 
Part Number 
Package 
Temp. Range and Operating Voltage 
Marking 
Supplied In 
aSC7531AM10 
10-Lead 
MSOP 
-40°C to 125°C, 3.3V 
531A 
Ayww 
2500 units Tape & 
Reel 
aSC7531BM10 
10-Lead 
MSOP 
-40°C to 125°C, 3.3V 
531B 
Ayww 
2500 units Tape & 
Reel 
          Ayww – Assembly site,  year,  workweek 
6 
7 
aSC7531A/ 
aSC7531B 
VCCP 
3.3V  
  aSC7531A/ 
aSC7531B 
SST 
Interface
SST 
ADD0 
1 
3 
4 
10 
2 
9 
12V 
5 
5V 
12V 
10 
5 
5V 
2N3904 
V
CCP
2.5V 
8 
7 
6 
CPU 
with aSC7531A 
with aSC7531B