?Semiconductor Components Industries, LLC, 2012
July, 2012 Rev. 6
1
Publication Order Number:
NCT1008/D
NCT1008
+15C Temperature Monitor
with Series Resistance
Cancellation
The NCT1008 is a dual-channel digital thermometer and
undertemperature/overtemperature alarm, intended for use in PCs and
thermal management systems. It is register-compatible with the
ADM1032 and ADT7461. A feature of the NCT1008 is series
resistance cancellation, where up to 1.5 kW (typical) of resistance in
series with the temperature monitoring diode can be automatically
cancelled from the temperature result, allowing noise filtering. The
NCT1008 has a configurable ALERT
output and an extended,
switchable temperature measurement range.
The NCT1008 can measure the temperature of a remote thermal
diode accurate to ?癈 and the ambient temperature accurate to ?癈.
The temperature measurement range defaults to 0癈 to +127癈,
compatible with the ADM1032, but it can be switched to a wider
measurement range of 64癈 to +191癈.
The NCT1008 communicates over a 2-wire serial interface,
compatible with system management bus (SMBus/I
2
C) standards. The
default SMBus/I
2
C address of the NCT1008 is 0x4C. An NCT1008D
is available with an SMBus/I
2
C address of 0x4D. This is useful if more
than one NCT1008 is used on the same SMBus/I
2
C.
An ALERT
output signals when the on-chip or remote temperature
is out of range. The THERM
output is a comparator output that allows
on/off control of a cooling fan. The ALERT
output can be
reconfigured as a second THERM
output, if required.
Features
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> On-chip and Remote Temperature Sensor
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> 0.25?/SPAN>C Resolution/1?/SPAN>C Accuracy on Remote Channel
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> 1?/SPAN>C Resolution/1?/SPAN>C Accuracy on Local Channel
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> Series Resistance Cancellation Up to 1.5 kW
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> Extended, Switchable Temperature Measurement Range
0癈 to +127癈 (Default) or 64癈 to +191癈
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> Register-compatible with ADM1032 and ADT7461
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> Remote THERM
Limit of 108癈
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> 2-wire SMBus/I
2
C Serial Interface with SMBus Alert Support
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> Programmable Over/Undertemperature Limits
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> Offset Registers for System Calibration
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> Up to Two Overtemperature Fail-safe THERM
Outputs
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> Small 8-lead DFN
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> 240 mA Operating Current, 5 mA Standby Current
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> Compatible with 1.8 V Logic
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> Pb-Free Packages are Available
Applications
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> Smart Phones
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> Desktop and Notebook Computers
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> Smart Batteries
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> Automotive
?SPAN class="pst NCT1008DMT3R2G_2296461_4"> Embedded Systems
MARKING DIAGRAMS
http://onsemi.com
PIN ASSIGNMENT
DFN8
CASE 506BJ
See detailed ordering and shipping information in the package
dimensions section on page 18 of this data sheet.
ORDERING INFORMATION
NCT
1008x
ALYWG
G
1
8
x
= C or D
A
= Assembly Location
L
= Wafer Lot
Y
= Year
W    = Work Week
G
= Pb-Free Package
(Note: Microdot may be in either location)
WDFN8
CASE 511AT
8xMG
G
1
V
DD
ALERT
/
THERM2
(Top View)
D+
D
THERM
SCLK
SDATA
GND
1
2
3
4
8
7
6
5
8x    = Device Code (Where x = C or D)
M    = Date Code
G
= Pb-Free Package
WDFN8
DFN8