ADVANCE INFORMATION
August 2006
LM95233
Dual Remote Diode and Local Temperature Sensor with
™
SMBus Interface, TCRITs and TruTherm Technology
n TruTherm technology accurately senses sub-micron
process thermal diodes
General Description
LM95233 is an 11-bit digital temperature sensor with a 2-wire
n 0.125˚C LSb temperature resolution
System Management Bus (SMBus) interface that can moni-
n 0.03125˚C LSb remote temperature resolution with
tor the temperature of two remote diodes as well as its own
digital filter enabled
temperature. The LM95233 can be used to very accurately
n
+127.875˚C/–128˚C and 0˚C/255˚C remote ranges
monitor the temperature of up to two external devices such
as microprocessors, graphics processors or diode-
connected 2N3904s. The LM95233’s TruTherm technology
allows sensing of 90nm or 65nm process thermal diodes
accurately.
n Programmable digital filters and analog front end filter
n Remote diode fault detection, model selection and offset
correction
n Mask and status register support
n 3 programmable TCRIT outputs with programmable
shared hysteresis
n Programmable conversion rate and shutdown mode
one-shot conversion control
n SMBus 2.0 compatible interface, supports TIMEOUT
n Three-level address pin
The LM95233 reports temperature in two different formats
for +127.875˚C/–128˚C range and 0˚C/255˚C range. The
LM95233 TCRIT1, TCRIT2 and TCRIT3 outputs are trig-
gered when any unmasked channel exceeds its correspond-
ing programmable limit and can be used to shutdown the
system, to turn on the system fans or as a microcontroller
interrupt function. The current status of the TCRIT1, TCRIT2
and TCRIT3 pins can be read back from the status registers.
Mask registers are available for further control of the TCRIT
outputs.
n 14-pin LLP package
Key Specifications
LM95233’s remote temperature channels have program-
mable digital filters to minimize unwanted TCRIT events
when temperature spikes are encountered.
j
Local Temperature Accuracy
2.0 ˚C (max)
0.75 ˚C (max)
j
Remote Diode Temperature
Accuracy
For optimum flexibility and accuracy each LM95233 channel
includes, registers for sub-micron process or 2N3904 diode
model selection as well as offset correction. A three level
address pin allows connection of up to 3 LM95233s to the
same SMBus master. The LM95233 includes power saving
functions such as: programmable conversion rate, shutdown
mode, and turn off of unused channels.
j
j
Supply Voltage
3.0 V to 3.6 V
0.5 mA (typ)
Average Supply Current (1Hz
conversion rate)
Applications
n Processor/Computer System Thermal Management
(e.g. Laptop, Desktop, Workstations, Server)
n Electronic Test Equipment
Features
n Accurately senses die temperature of 2 remote ICs or
n Office Electronics
diode junctions and local temperature
Connection Diagram
LLP-14
20206301
TOP VIEW
™
TruTherm is a trademark of National Semiconductor Corporation.
© 2006 National Semiconductor Corporation
DS202063
www.national.com