LM95213CISDX/NOPB - National Semiconductor

March 2007

LM95213

2-Diode Input and Local Digital Temperature Sensor with

Two-Wire Interface and TCRIT Outputs

General Description

LM95213 is an 11-bit digital temperature sensor with a 2-wire

System Management Bus (SMBus) interface that can monitor

the temperature of two remote diodes as well as its own tem-

perature. The LM95213 can be used to very accurately mon-

itor the temperature of up to two external devices such as

microprocessors, graphics processors or diode-connected

2N3904s.

The LM95213 reports temperature in two different formats for

+127.875°C/–128°C range and 0°C/255°C range. The

LM95213 TCRIT1, TCRIT2 and TCRIT3 outputs are triggered

when any unmasked channel exceeds its corresponding pro-

grammable limit and can be used to shutdown the system, to

turn on the system fans or as a microcontroller interrupt func-

tion. The current status of the TCRIT1, TCRIT2 and TCRIT3

pins can be read back from the status registers. Mask regis-

ters are available for further control of the TCRIT outputs.

LM95213's remote temperature channels have pro-

grammable digital filters to minimize unwanted TCRIT events

when temperature spikes are encountered.

For optimum flexibility and accuracy each LM95213 channel

includes offset correction registers for targeting diodes other

than the 2N3904. A three level address pin allows connection

of up to 3 LM95213s to the same SMBus master. The

LM95213 includes power saving functions such as: pro-

grammable conversion rate, shutdown mode, and turn off of

unused channels.

Features

■Accurately senses die temperature of 2 remote ICs or

diode junctions and local temperature

■0.125°C LSb temperature resolution

■0.03125°C LSb remote temperature resolution with digital

filter enabled

■+127.875°C/–128°C and 0°C/255°C remote ranges

■Programmable digital filters and analog front end filter

■Remote diode fault detection, model selection and offset

correction

■Mask and status register support

■3 programmable TCRIT outputs with programmable

shared hysteresis

■Programmable conversion rate and shutdown mode one-

shot conversion control

■SMBus 2.0 compatible interface, supports TIMEOUT

■Three-level address pin

■14-pin LLP package

Key Specifications

■ Local Temperature Accuracy ±2.0 °C (max)

■ Remote Diode Temperature Accuracy ±1.1 °C (max)

■ Supply Voltage 3.0 V to 3.6 V

■ Average Supply Current (1Hz

conversion rate)

0.57 mA (typ)

Applications

■Processor/Computer System Thermal Management

(e.g. Laptop, Desktop, Workstations, Server)

■Electronic Test Equipment

■Office Electronics

Connection Diagram

LLP-14

30013801

TOP VIEW

TruTherm™ is a trademark of National Semiconductor Corporation.

Intel™ is a trademark of Intel Corporation.

Pentium™ is a trademark of Intel Corporation.

LM95213 2-Diode Input and Local Digital Temperature Sensor with Two-Wire Interface and

TCRIT Outputs

Ordering Information

Part Number Package

Marking

NS Package

Number

Transport

Media

LM95213CISD 95213CI SDA14B (LLP-14) 1000 Units on Tape and Reel

LM95213CISDX 95213CI SDA14B (LLP-14) 4500 Units on Tape and Reel

Simplified Block Diagram

30013802

Pin Descriptions

Label Pin # Function Typical Connection

NC 1 No Connect Not connected. May be left floating, connected to GND or

VDD.

VDD 2 Positive Supply Voltage Input DC Voltage from 3.0 V to 3.6 V. VDD should be bypassed with

a 0.1µF capacitor in parallel with 100pF. The 100pF capacitor

should be placed as close as possible to the power supply

pin. Noise should be kept below 200 mVp-p, a 10 µF capacitor

may be required to achieve this.

NC 3 No Connect Not connected. May be left floating, connected to GND or

VDD.

NC 4 No Connect Not connected. May be left floating, connected to GND or

VDD.

D− 5 Diode Return Current Sink To all Diode Cathodes. Common D- pin for all two remote

diodes.

www.national.com 2

LM95213

Label Pin # Function Typical Connection

D2+ 6 Diode Current Source To second Diode Anode. Connected to remote discrete diode-

connected transistor junction or to the diode-connected

transistor junction on a remote IC whose die temperature is

being sensed. A capacitor is not required between D2+ and

D-. A 100 pF capacitor between D2+ and D- can be added

and may improve perfomance in noisy systems. Float this pin

if this thermal diode is not used.

D1+ 7 Diode Current Source To first Diode Anode. Connected to remote discrete diode-

connected transistor junction or to the diode-connected

transistor junction on a remote IC whose die temperature is

being sensed. A capacitor is not required between D1+ and

D-. A 100 pF capacitor between D1+ and D- can be added

and may improve perfomance in noisy systems. Float this pin

if this thermal diode is not used.

GND 8 Power Supply Ground System low noise ground.

A0 9 Dgital Input SMBus slave address select pin. Selects one of three

addresses. Can be tied to VDD, GND, or to the middle of a

resistor divider connected between VDD and GND.

TCRIT1 10 Digital Output, Open-Drain Critical temperature output 1. Requires pull-up resistor. Active

"LOW".

TCRIT2 11 Digital Output, Open-Drain Critical temperature output 2. Requires pull-up resistor. Active

"LOW".

SMBDAT 12 SMBus Bi-Directional Data

Line, Open-Drain Output

From and to Controller; may require an external pull-up

resistor

SMBCLK 13 SMBus Clock Input From Controller; may require an external pull-up resistor

TCRIT3 14 Digital Output, Open-Drain Critical temperature output 3. Requires pull-up resistor. Active

"LOW".

3 www.national.com

LM95213

Typical Application

30013803

www.national.com 4

LM95213

Absolute Maximum Ratings (Note 1)
Supply Voltage −0.3V to 6.0V
Voltage at SMBDAT, SMBCLK,
TCRIT1, TCRIT2, TCRIT3 −0.5V to 6.0V
Voltage at Other Pins −0.3V to (VDD + 0.3V)
D− Input Current   ±1 mA
Input Current at All Other Pins (Note 2) ±5 mA
Package Input Current (Note 2) 30 mA
SMBDAT, TCRIT1, TCRIT2,
TCRIT3 Output Sink Current 10 mA
Storage Temperature −65°C to +150°C
ESD Susceptibility (Note 4)
  Human Body Model 2000V
  Machine Model 200V
  Charge Device Model 1000V
Soldering process must comply with National’s reflow
temperature profile specifications. Refer to http://
www.national.com/packaging/. (Note 3)
Operating Ratings
(Notes 1, 5)
Operating Temperature Range −40°C to +140°C
Electrical Characteristics Temperature
Range TMIN ≤ TA ≤ TMAX
LM95213CISD −40°C ≤ TA ≤
+125°C
Supply Voltage Range (VDD)+3.0V to +3.6V
Temperature-to-Digital Converter Electrical Characteristics
Unless otherwise noted, these specifications apply for VDD = +3.0Vdc to 3.6Vdc. Boldface limits apply for TA = TJ = TMIN ≤ TA
≤ TMAX;  all other limits TA = TJ = +25°C, unless otherwise noted.
Parameter Conditions Typical Limits Units
    (Note 6) (Note 7) (Limit)
Temperature Error Using Local Diode TA = -40°C to +125°C, (Note 8) ±1 ±2 °C (max)
Temperature Error Using Remote Diode (Note
9)
TA = +25°C to +85°C
TD = +60°C to +100°C
MMBT3904
Transistor
 ±1.1 °C (max)
TA = +25°C to +85°C
TD = −40°C to +125°C
MMBT3904
Transistor
 ±1.3 °C (max)
TA = −40°C to +85°C
TD = −40°C to +125°C
MMBT3904
Transistor
 ±3.0 °C (max)
TA = −40°C to +85°C
TD = 125°C to +140°C
MMBT3904
Transistor
 ±3.3 °C (max)
Local Diode Measurement Resolution   11   Bits
0.125   °C
Remote Diode Measurement Resolution Digital Filter Off 11   Bits
0.125   °C
Digital Filter On (Remote Diodes 1 and 2
only)
13   Bits
0.03125   °C
Conversion Time of All Temperatures at the
Fastest Setting (Note 11)
All Channels are Enabled in Default
State
1100 1210 ms (max)
1 External Channel 31 34 ms (max)
Local only 30 33 ms (max)
Quiescent Current (Note 10) SMBus Inactive, 1Hz Conversion Rate,
channels in default state
570 800 µA (max)
Shutdown 360 µA
D− Source Voltage   0.4   V
Remote Diode Source Current High level 160 230 µA (max)
Low level 10  
Power-On Reset Threshold Measured on VDD input, falling edge   2.8
1.6
V (max)
V (min)
TCRIT1 Pin Temperature Threshold Default Diodes only +110   °C
TCRIT2 Pin Temperature Threshold Default all channels +85   °C
5 www.national.com
LM95213

Logic Electrical Characteristics

DIGITAL DC CHARACTERISTICS

Unless otherwise noted, these specifications apply for VDD = +3.0Vdc to 3.6Vdc. Boldface limits apply for TA = TJ = TMIN to

TMAX; all other limits TA= TJ=+25°C, unless otherwise noted.

Symbol Parameter Conditions Typical Limits Units

(Note 6) (Note 7) (Limit)

SMBDAT, SMBCLK INPUTS

VIN(1) Logical “1” Input Voltage 2.1 V (min)

VIN(0) Logical “0”Input Voltage 0.8 V (max)

VIN(HYST) SMBDAT and SMBCLK Digital Input Hysteresis 400 mV

IIN(1) Logical “1” Input Current VIN = VDD 0.005 10 µA (max)

IIN(0) Logical “0” Input Current VIN = 0V −0.005 -10 µA (max)

CIN Input Capacitance 5 pF

A0 DIGITAL INPUT

VIH Input High Voltage 0.90 × VDD V (min)

VIM Input Middle Voltage 0.57 × VDD V (max)

0.43 × VDD V (min)

VIL Input Low Voltage 0.10 × VDD V (max)

IIN(1) Logical "1" Input Current VIN = VDD −0.005 −10 µA (min)

IIN(0) Logical "0" Input Current VIN = 0V 0.005 10 µA (max)

CIN Input Capacitance 5 pF

SMBDAT, TCRIT1, TCRIT2, TCRIT3 DIGITAL OUTPUTS

IOH High Level Output Current VOH = VDD 10 µA (max)

VOL(SMBDAT) SMBus Low Level Output Voltage IOL = 4 mA

IOL = 6 mA

0.4

0.6

V (max)

VOL(TCRIT) TCRIT1, TCRIT2, TCRIT3 Low Level Output

Voltage

IOL= 6 mA 0.4 V (max)

COUT Digital Output Capacitance 5 pF

www.national.com 6

LM95213

SMBus DIGITAL SWITCHING CHARACTERISTICS

Unless otherwise noted, these specifications apply for VDD=+3.0 Vdc to +3.6 Vdc, CL (load capacitance) on output lines = 80 pF.

Boldface limits apply for TA = TJ = TMIN to TMAX; all other limits TA = TJ = +25°C, unless otherwise noted.

The switching characteristics of the LM95213 fully meet or exceed the published specifications of the SMBus version 2.0. The

following parameters are the timing relationships between SMBCLK and SMBDAT signals related to the LM95213. They adhere

to but are not necessarily the SMBus bus specifications.

Symbol Parameter Conditions Typical Limits Units

(Note 6) (Note 7) (Limit)

fSMB SMBus Clock Frequency 100

kHz (max)

kHz (min)

tLOW SMBus Clock Low Time from VIN(0)max to VIN(0)max 4.7

µs (min)

ms (max)

tHIGH SMBus Clock High Time from VIN(1)min to VIN(1)min 4.0 µs (min)

tR,SMB SMBus Rise Time (Note 12) 1 µs (max)

tF,SMB SMBus Fall Time (Note 13) 0.3 µs (max)

tOF Output Fall Time CL = 400 pF,

IO = 3 mA, (Note 13)

250 ns (max)

tTIMEOUT SMBDAT and SMBCLK Time Low for Reset of

Serial Interface (Note 14)

ms (min)

ms (max)

tSU;DAT Data In Setup Time to SMBCLK High 250 ns (min)

tHD;DAT Data Out Stable after SMBCLK Low 300

1075

ns (min)

ns (max)

tHD;STA Start Condition SMBDAT Low to SMBCLK Low

(Start condition hold before the first clock falling

edge)

100 ns (min)

tSU;STO Stop Condition SMBCLK High to SMBDAT Low

(Stop Condition Setup)

100 ns (min)

tSU;STA SMBus Repeated Start-Condition Setup Time,

SMBCLK High to SMBDAT Low

0.6 µs (min)

tBUF SMBus Free Time Between Stop and Start

Conditions

1.3 µs (min)

SMBus Communication

30013809

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. DC and AC electrical specifications do not apply when operating

the device beyond its rated operating conditions.

Note 2: When the input voltage (VI) at any pin exceeds the power supplies (VI < GND or VI > VDD), the current at that pin should be limited to 5 mA.

Parasitic components and or ESD protection circuitry are shown in the table below for the LM95213's pins.

7 www.national.com

LM95213

Pin # Label Circuit Circuits for Pin ESD Protection Structure

1 NC –

Circuit A

2 VDD A

3 NC –

4 NC –

5 D- A

6 D2+ A

7 D1+ A

8 GND –

Circuit B

9 A0 B

10 TCRIT1 B

11 TCRIT2 B

12 SMBDAT B

13 SMBCLK B

14 TCRIT2 B

Note 3: Reflow temperature profiles are different for packages containing lead (Pb) than for those that do not.

Note 4: Human body model, 100 pF discharged through a 1.5 kΩ resistor. Machine model, 200 pF discharged directly into each pin. Charged Device Model

(CDM) simulates a pin slowly acquiring charge (such as from a device sliding down the feeder in an automated assembler) then rapidly being discharged.

Note 5: Thermal resistance junction-to-ambient when attached to a 4 layer printed circuit board per JEDEC standard JESD51-7:

– 14-lead LLP = 90°C/W (no thermal vias, no airflow)

– 14-lead LLP = 63°C/W (1 thermal via, no airflow)

– 14-lead LLP = 43°C/W (6 thermal vias, no airflow)

– 14-lead LLP = 31°C/W (6 thermal vias, 900 ln. ft. / min. airflow)

Note, all quoted values include +15% error factor from nominal value.

Note 6: Typicals are at TA = 25°C and represent most likely parametric norm.

Note 7: Limits are guaranteed to National's AOQL (Average Outgoing Quality Level).

Note 8: Local temperature accuracy does not include the effects of self-heating. The rise in temperature due to self-heating is the product of the internal power

dissipation of the LM95213 and the thermal resistance. See (Note 5) for the thermal resistance to be used in the self-heating calculation.

Note 9: The accuracy of the LM95213CISD is guaranteed when using a typical thermal diode of an MMBT3904 diode-connected transistor. For further information

on other thermal diodes see applications Section 3.1 "Diode Non-ideality" or send email to hardware.monitor.team@national.com.

Note 10: Quiescent current will not increase substantially with an SMBus communication.

Note 11: This specification is provided only to indicate how often temperature data is updated. The LM95213 can be read at any time without regard to conversion

state (and will yield last conversion result).

Note 12: The output rise time is measured from (VIN(0)max − 0.15V) to (VIN(1)min + 0.15V).

Note 13: The output fall time is measured from (VIN(1)min + 0.15V) to (VIN(0)max − 0.15V).

Note 14: Holding the SMBDAT and/or SMBCLK lines Low for a time interval greater than tTIMEOUT will reset the LM95213's SMBus state machine, therefore setting

SMBDAT and SMBCLK pins to a high impedance state.

www.national.com 8

LM95213

Typical Performance Characteristics

Conversion Rate Effect on

Average Power Supply Current

30013806

Thermal Diode Capacitor or PCB

Leakage Current Effect on

Remote Diode Temperature Reading

30013823

Remote Temperature Reading Sensitivity to

Thermal Diode Filter Capacitance,

30013807

1.0 Functional Description

LM95213 is an 11-bit digital temperature sensor with a 2-wire

System Management Bus (SMBus) interface that can monitor

the temperature of two remote diodes as well as its own tem-

perature. The LM95213 can be used to very accurately mon-

itor the temperature of up to two external devices such as

microprocessors, graphics processors or diode-connected

2N3904 transistor.

The LM95213 reports temperature in two different formats for

+127.875°C/–128°C range and 0°C/255°C range. The

LM95213 has a Sigma-Delta ADC (Analog-to-Digital Con-

verter) core which provides the first level of noise imunity. For

improved performance in a noisy environment the LM95213

includes programmable digital filters for Remote Diode 1 and

2 temperature readings. When the digital filters are invoked

the resolution for Remote Diode 1 and 2 readings increases

to 0.03125°C. For maximum flexibility and best accuracy the

LM95213 includes offset registers that allow calibration of

other diode types.

Diode fault detection circuitry in the LM95213 can detect the

absence or fault state of a remote diode: whether D+ is short-

ed to VDD, D- or ground, or whether D+ is floating.

The LM95213 TCRIT1, TCRIT2 and TCRIT3 active low out-

puts are triggered when any unmasked channel exceeds its

corresponding programmable limit and can be used to shut-

down the system, to turn on the system fans or as a micro-

controller interrupt function. The current status of the

TCRIT1, TCRIT2 and TCRIT3 pins can be read back from the

status registers via the SMBus interface. The remote chan-

nels have two separate limits each that control the TCRIT1

and TCRIT2 pins. The TCRIT3 pin shares the limits of the

TCRIT2 pin but allows for different masking options. All limits

have a shared programmable hysteresis register.

Remote Diode temperature channels have programmable

digital filters in order to avoid false triggering the TCRIT pins.

LM95213 has a three-level address pin to connect up to 3

devices to the same SMBus master. LM95213 also has pro-

grammable conversion rate register as well as a shutdown

mode for power savings. One round of conversions can be

triggered in shutdown mode by writing to the one-shot register

through the SMBus interface. LM95213 can be programmed

to turn off unused channels for more power savings.

The LM95213 register set has an 8-bit data structure and in-

cludes:

9 www.national.com

LM95213

1. Temperature Value Registers with signed format

—Most-Significant-Byte (MSB) and Least-Significant-

Byte (LSB) Local Temperature

—MSB and LSB Remote Temperature 1

—MSB and LSB Remote Temperature 2

2. Temperature Value Registers with unsigned format

—MSB and LSB Remote Temperature 1

—MSB and LSB Remote Temperature 2

3. Diode Configuration Registers

—Remote 1 Offset

—Remote 2 Offset

4. General Configuration Registers

—Configuration (Standby, Conversion Rate)

—Channel Conversion Enable

—Filter Setting for Remote 1 and 2

—1-Shot

5. Status Registers

—Main Status Register (Busy bit, Not Ready, Status

—Status 1 (diode fault)

—Status 2 (TCRIT1)

—Status 3 (TCRIT2)

—Status 4 (TCRIT3)

6. Mask Registers

—TCRIT1 Mask

—TCRIT2 Mask

—TCRIT3 Mask

7. Limit Registers

—Local Tcrit Limit

—Remote 1 Tcrit-1 Limit

—Remote 2 Tcrit-1 Limit

—Remote 1 Tcrit-2 and Tcrit-3 Limit

—Remote 2 Tcrit-2 and Tcrit-3 Limit

—Common Tcrit Hysteresis

8. Manufacturer ID Register

9. Revision ID Register

1.1 CONVERSION SEQUENCE

The LM95213 takes approximately 92 ms to convert the Local

Temperature, Remote Temperatures 1 and 2, and to update

all of its registers. These conversions for each thermal diode

are addressed in a round robin sequence. Only during the

conversion process the busy bit (D7) in Status register (02h)

is high. The conversion rate may be modified by the Conver-

sion Rate bits found in the Configuration Register (03h).

When the conversion rate is modified a delay is inserted be-

tween each round of conversions, the actual time for each

round remains at 92 ms (typical all channels enabled). The

time a round takes depends on the number of channels that

are on. Different conversion rates will cause the LM95213 to

draw different amounts of average supply current as shown

in Figure 1. This curve assumes all the channels are on. If

channels are turned off the average current will drop since the

round robin time will decrease and the shutdown time will in-

crease during each conversion interval.

30013806

FIGURE 1. Conversion Rate Effect on Power Supply

Current

1.2 POWER-ON-DEFAULT STATES

LM95213 always powers up to these known default states.

The LM95213 remains in these states until after the first con-

version.

1. All Temperature readings set to 0°C until the end of the

first conversion

2. Remote offset for all channels 0°C

3. Configuration: Active converting

4. Continuous conversion with all channels enabled,

time = 1s

5. Enhanced digital filter enabled for Remote 1 and 2

6. Status Registers depends on state of thermal diode

inputs

7. Local and Remote Temperature Limits for TCRIT1,

TCRIT2 and TCRIT3 outputs:

Output Pin Temperature Channel Limit

Remote 2

(°C)

Remote 1

(°C)

Local

(°C)

TCRIT1 110 110 Masked,

TCRIT2 85 85 85

TCRIT3 Masked,

Masked,

8. Manufacturers ID set to 01h

9. Revision ID set to 7Bh

1.3 SMBus INTERFACE

The LM95213 operates as a slave on the SMBus, so the

SMBCLK line is an input and the SMBDAT line is bidirectional.

The LM95213 never drives the SMBCLK line and it does not

support clock stretching. According to SMBus specifications,

the LM95213 has a 7-bit slave address. Three SMBus device

address can be selected by connecting A0 (pin 6) to either

Low, Mid-Supply or High voltages. The LM95213 has the fol-

lowing SMBus slave address:

www.national.com 10

LM95213

A0 Pin State SMBus Device Address A[6:0]

Hex Binary

Low 18h 001 1000

Mid-Supply 2Ah 010 1010

High 2Bh 010 1011

1.4 TEMPERATURE CONVERSION SEQUENCE

Each of the 3 temperature channels of LM95213 can be

turned OFF independent from each other via the Channel

Enable Register. Turning off unused channels will increase

the conversion speed in the fastest conversion speed mode.

If the slower conversion speed settings are used, disabling

unused channels will reduce the average power consumption

of LM95213.

1.5 DIGITAL FILTER

In order to suppress erroneous remote temperature readings

due to noise as well as increase the resolution of the temper-

ature, the LM95213 incorporates a digital filter for Remote 1

and 2 Temperature Channels. When a filter is enabled the

filtered readings are used for the TCRIT comparisons. There

are two possible digital filter settings that are enabled through

the Filter Setting Register at register address 0Fh. The filter

for each channel can be set according to the following table:

R1F[1:0] or R2F[1:0] Filter Setting

0 0 No Filter

0 1 Filter (equivalent to Level 2

filter of the LM86/LM89)

1 0 Reserved

1 1 Enhanced Filter (Filter with

transient noise clipping)

Figure 2 describes the filter output in response to a step input

and an impulse input.

30013825

a) Seventeen and fifty degree step

response

30013826

b) Impulse response with input

transients less than 4°C

30013827

c) Impulse response with input

transients great than 4°C

FIGURE 2. Filter Impulse and Step Response Curves

30013828

FIGURE 3. Digital Filter Response in a typical processor

system. The filter curves were purposely offset for

clarity.

Figure 3 shows the filter in use in a typical processor system.

Note that the two curves have been purposely offset for clar-

ity. Inserting the filter does not induce an offset as shown.

1.6 TEMPERATURE DATA FORMAT

Temperature data can only be read from the Local and Re-

mote Temperature value registers. The data format for all

temperature values is left justified 16-bit word available in two

8-bit registers. Unused bits will always report "0". All temper-

ature data is clamped and will not roll over when a tempera-

ture exceeds full-scale value.

Remote temperature data for all channels can be represented

by an 11-bit, two's complement word or unsigned binary word

with an LSb (Least Significant Bit) equal to 0.125°C.

11-bit, 2's complement (10-bit plus sign)

Temperature Digital Output

Binary Hex

+125°C 0111 1101 0000 0000 7D00h

+25°C 0001 1001 0000 0000 1900h

+1°C 0000 0001 0000 0000 0100h

+0.125°C 0000 0000 0010 0000 0020h

0°C 0000 0000 0000 0000 0000h

−0.125°C 1111 1111 1110 0000 FFE0h

−1°C 1111 1111 0000 0000 FF00h

11 www.national.com

LM95213

Temperature Digital Output

Binary Hex

−25°C 1110 0111 0000 0000 E700h

−55°C 1100 1001 0000 0000 C900h

11-bit, unsigned binary

Temperature Digital Output

Binary Hex

+255.875°C 1111 1111 1110 0000 FFE0h

+255°C 1111 1111 0000 0000 FF00h

+201°C 1100 1001 0000 0000 C900h

+125°C 0111 1101 0000 0000 7D00h

+25°C 0001 1001 0000 0000 1900h

+1°C 0000 0001 0000 0000 0100h

+0.125°C 0000 0000 0010 0000 0020h

0°C 0000 0000 0000 0000 0000h

When the digital filter is enabled on Remote 1 and 2 channels

temperature data is represented by a 13-bit unsigned binary

or 12-bit plus sign (two's complement) word with an LSb equal

to 0.03125°C.

13-bit, 2's complement (12-bit plus sign)

Temperature Digital Output

Binary Hex

+125°C 0111 1101 0000 0000 7D00h

+25°C 0001 1001 0000 0000 1900h

+1°C 0000 0001 0000 0000 0100h

+0.03125°C 0000 0000 0000 1000 0008h

0°C 0000 0000 0000 0000 0000h

−0.03125°C 1111 1111 1111 1000 FFF8h

−1°C 1111 1111 0000 0000 FF00h

−25°C 1110 0111 0000 0000 E700h

−55°C 1100 1001 0000 0000 C900h

13-bit, unsigned binary

Temperature Digital Output

Binary Hex

+255.875°C 1111 1111 1110 0000 FFE0h

+255°C 1111 1111 0000 0000 FF00h

+201°C 1100 1001 0000 0000 C900h

+125°C 0111 1101 0000 0000 7D00h

+25°C 0001 1001 0000 0000 1900h

+1°C 0000 0001 0000 0000 0100h

+0.03125°C 0000 0000 0000 1000 0008h

0°C 0000 0000 0000 0000 0000h

Local Temperature data is only represented by an 11-bit,

two's complement, word with an LSb equal to 0.125°C.

11-bit, 2's complement (10-bit plus sign)

Temperature Digital Output

Binary Hex

+125°C 0111 1101 0000 0000 7D00h

+25°C 0001 1001 0000 0000 1900h

Temperature Digital Output

Binary Hex

+1°C 0000 0001 0000 0000 0100h

+0.125°C 0000 0000 0010 0000 0020h

0°C 0000 0000 0000 0000 0000h

−0.125°C 1111 1111 1110 0000 FFE0h

−1°C 1111 1111 0000 0000 FF00h

−25°C 1110 0111 0000 0000 E700h

−55°C 1100 1001 0000 0000 C900h

1.7 SMBDAT OPEN-DRAIN OUTPUT

The SMBDAT output is an open-drain output and does not

have internal pull-ups. A “high” level will not be observed on

this pin until pull-up current is provided by some external

source, typically a pull-up resistor. Choice of resistor value

depends on many system factors but, in general, the pull-up

resistor should be as large as possible without effecting the

SMBus desired data rate. This will minimize any internal tem-

perature reading errors due to internal heating of the

LM95213. The maximum resistance of the pull-up to provide

a 2.1V high level, based on LM95213 specification for High

Level Output Current with the supply voltage at 3.0V, is 82

kΩ (5%) or 88.7 kΩ (1%).

1.8 TCRIT1, TCRIT2, AND TCRIT3 OUTPUTS

The LM95213's TCRIT pins are active-low open-drain outputs

and do not include internal pull-up resistors. A “high” level will

not be observed on these pins until pull-up current is provided

by some external source, typically a pull-up resistor. Choice

of resistor value depends on many system factors but, in gen-

eral, the pull-up resistor should be as large as possible without

effecting the performance of the device receiving the signal.

This will minimize any internal temperature reading errors due

to internal heating of the LM95213. The maximum resistance

of the pull-up to provide a 2.1V high level, based on LM95213

specification for High Level Output Current with the supply

voltage at 3.0V, is 82 kΩ (5%) or 88.7 kΩ (1%). The three

TCRIT pins can each sink 6 mA of current and still guarantee

a "Logic Low" output voltage of 0.4V. If all three pins are set

at maximum current this will cause a power dissipation of 7.2

mW. This power dissipation combined with a thermal resis-

tance of 77.8°C/W will cause the LM95213's junction temper-

ature to rise approximately 0.6°C and thus cause the Local

temperature reading to shift. This can only be cancelled out if

the environment that the LM95213 is enclosed in has stable

and controlled air flow over the LM95213, as airflow can

cause the thermal resistance to change dramatically.

1.9 TCRIT LIMITS AND TCRIT OUTPUTS

Figure 4 describes a simplified diagram of the temperature

comparison and status register logic. Figure 5 describes a

simplified logic diagram of the circuitry associated with the

status registers, mask registers and the TCRIT output pins.

www.national.com 12

LM95213

30013850

FIGURE 4. Temperature Comparison Logic and Status Register Simplified Diagram

13 www.national.com

LM95213

30013851

a) TCRIT1 Mask Register, Status Register 1 and 2, and

TCRIT1 output logic diagram.

30013852

b) TCRIT2 Mask Register, Status Register 1 and 3, and

TCRIT2 output logic diagram.

30013853

c) TCRIT3 Mask Register, Status Register 1 and 4, and

TCRIT3 output logic diagram.

FIGURE 5. Logic diagrams for the TCRIT1, TCRIT2, and

TCRIT3 outputs.

If enabled, local temperature is compared to the user pro-

grammable Local Tcrit Limit Register (Default Value = 85°C).

The result of this comparison is stored in Status Register 2,

Status Register 3 and Status Register 4 (see Figure 4).The

comparison result can trigger TCRIT1 pin, TCRIT2 pin or

TCRIT3 pin depending on the settings in the TCRIT1 Mask,

TCRIT2 Mask and TCRIT3 Mask Registers (see Figure 5).

The comparison result can also be read back from the Status

If enabled, remote temperature 1 is compared to the user

programmable Remote 1 Tcrit-1 Limit Register (Default Value

110°C) and Remote 1 Tcrit-2 Limit Register (Default Value =

85°C). The result of this comparison is stored in Status Reg-

ister 2, Status Register 3 and Status Register 4 (see Figure

4). The comparison result can trigger TCRIT1 pin, TCRIT2 pin

or TCRIT3 pin depending on the settings in the TCRIT1 Mask,

TCRIT2 Mask and TRCIT3 Mask Registers (see Figure 5).

The comparison result can also be read back from the Status

mote temperature 2 operates in a similar manner to remote

temperature 1 using its associated user programmable limit

registers: Remote 2 Tcrit-1 Limit Register (Default Value 110°

C) and Remote 2 Tcrit-2 Limit Register (Default Value = 85°

C).

Limit assignments for each TCRIT output pin:

TCRIT1 TCRIT2 TCRIT3

Remote 2 Remote 2

Tcrit-1 Limit

Remote 2

Tcrit-2 Limit

Remote 2

Tcrit-2 Limit

Remote 1 Remote 1

Tcrit-1 Limit

Remote 1

Tcrit-2 Limit

Remote 1

Tcrit-2 Limit

Local Local

Tcrit Limit

Local

Tcrit Limit

Local

Tcrit Limit

www.national.com 14

LM95213

30013830

FIGURE 6. TCRIT response diagram (masking options not included)

The TCRIT response diagram of Figure 6 shows the local

temperature interaction with the Tcrit limit and hysteresis val-

ue. As can be seen in the diagram when the local temperature

exceeds the Tcrit limit register value the LTn Status bit is set

and the T_CRITn output(s) is/are activated. The Status bit(s)

and outputs are not deactivated until the temperature goes

below the value calculated by subtracting the Common Hys-

teresis value programmed from the limit. This diagram mainly

shows an example function of the hysteresis and is not meant

to show complete function of the possible settings and options

of all the TCRIT outputs and limit values.

1.10 DIODE FAULT DETECTION

The LM95213 is equipped with operational circuitry designed

to detect fault conditions concerning the remote diodes. In the

event that the D+ pin is detected as shorted to GND, D−,

VDD or D+ is floating, the Remote Temperature reading

is –128.000 °C if signed format is selected and 0 °C if un-

signed format is selected. In addition, the appropriate status

1.11 COMMUNICATING WITH THE LM95213

The data registers in the LM95213 are selected by the Com-

mand Register. At power-up the Command Register is set to

“00”, the location for the Read Local Temperature Register.

The Command Register latches the last location it was set to.

Each data register in the LM95213 falls into one of three types

of user accessibility:

1. Read only

2. Write only

3. Write/Read same address

A Write to the LM95213 will always include the address byte

and the command byte. A write to any register requires one

data byte.

Reading the LM95213 can take place either of two ways:

1. If the location latched in the Command Register is correct

(most of the time it is expected that the Command

Registers because that will be the data most frequently

read from the LM95213), then the read can simply

consist of an address byte, followed by retrieving the data

byte.

2. If the Command Register needs to be set, then an

address byte, command byte, repeat start, and another

address byte will accomplish a read.

The data byte has the most significant bit first. At the end of

a read, the LM95213 can accept either acknowledge or No

Acknowledge from the Master (No Acknowledge is typically

used as a signal for the slave that the Master has read its last

byte). It takes the LM95213 95 ms (typical, all channels en-

abled) to measure the temperature of the remote diodes and

internal diode. When retrieving all 11 bits from a previous re-

mote diode temperature measurement, the master must in-

sure that all 11 bits are from the same temperature

conversion. This may be achieved by reading the MSB reg-

ister first. The LSB will be locked after the MSB is read. The

LSB will be unlocked after being read. If the user reads MSBs

consecutively, each time the MSB is read, the LSB associated

with that temperature will be locked in and override the pre-

vious LSB value locked-in.

15 www.national.com

LM95213

30013810

(a) Serial Bus Write to the internal Command Register followed by a the Data Byte

30013811

(b) Serial Bus Write to the Internal Command Register

30013812

30013814

(d) Serial Bus Write followed by a Repeat Start and Immediate Read

FIGURE 7. SMBus Timing Diagrams

1.12 SERIAL INTERFACE RESET

In the event that the SMBus Master is RESET while the

LM95213 is transmitting on the SMBDAT line, the LM95213

must be returned to a known state in the communication pro-

tocol. This may be done in one of two ways:

1. When SMBDAT is LOW, the LM95213 SMBus state

machine resets to the SMBus idle state if either SMBDAT

or SMBCLK are held low for more than 35ms (tTIMEOUT).

Note that according to SMBus specification 2.0 all

devices are to timeout when either the SMBCLK or

SMBDAT lines are held low for 25-35ms. Therefore, to

www.national.com 16

LM95213

insure a timeout of all devices on the bus the SMBCLK

or SMBDAT lines must be held low for at least 35ms.

2. When SMBDAT is HIGH, have the master initiate an

SMBus start. The LM95213 will respond properly to an

SMBus start condition at any point during the

communication. After the start the LM95213 will expect

an SMBus Address address byte.

1.13 ONE-SHOT CONVERSION

The One-Shot register is used to initiate a round of conver-

sions and comparisons when the device is in standby mode,

after which the device returns to standby. This is not a data

conversion. The data written to this address is irrelevant and

is not stored. A zero will always be read from this register. All

the channels that are enabled in the Channel Enable Register

will be converted once and the TCRIT1, TCRIT2 and

TCRIT3 pins will reflect the comparison results based on this

round of conversion results of the channels that are not

masked.

2.0 LM95213 Registers

Command register selects which registers will be read from or written to. Data for this register should be transmitted during the

Command Byte of the SMBus write communication.

P7 P6 P5 P4 P3 P2 P1 P0

Command Byte

P0-P7: Command

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Local Temp MSB 0x10 RO SIGN 64 32 16 8 4 2 1 –

Local Temp LSB 0x20 RO 1/2 1/4 1/8 0 0 0 0 0 –

Remote Temp 1 MSB – Signed 0x11 RO SIGN 64 32 16 8 4 2 1 –

Remote Temp 1 LSB – Signed,

Digital Filter Off 0x21 RO 1/2 1/4 1/8

0 0

0 0 0 –

Remote Temp 1 LSB – Signed,

Digital Filter On 1/16 1/32

Remote Temp 2 MSB – Signed 0x12 RO SIGN 64 32 16 8 4 2 1 –

Remote Temp 2 LSB – Signed,

Digital Filter Off 0x22 RO 1/2 1/4 1/8

0 0

0 0 0 –

Remote Temp 2 LSB – Signed,

Digital Filter On 1/16 1/32

Remote Temp 1 MSB – Unsigned 0x19 RO 128 64 32 16 8 4 2 1 –

Remote Temp 1 LSB – Unsigned,

Digital Filter Off 0x29 RO 1/2 1/4 1/8

0 0

0 0 0 –

Remote Temp 1 LSB – Unsigned,

Digital Filter On 1/16 1/32

Remote Temp 2 MSB – Unsigned 0x1A RO 128 64 32 16 8 4 2 1 –

Remote Temp 2 LSB – Unsigned,

Digital Filter Off 0x2A RO 1/2 1/4 1/8

0 0

0 0 0 –

Remote Temp 2 LSB – Unsigned,

Digital Filter On 1/16 1/32

Remote 1 Offset 0x31 R/W SIGN 32 16 8 4 2 1 1/2 0x00

Remote 2 Offset 0x32 R/W SIGN 32 16 8 4 2 1 1/2 0x00

Configuration 0x03 R/W –STBY – – – – – – 0x00

Conversion Rate 0x04 R/W – – – – – – CR1 CR0 0x02

Channel Conversion Enable 0x05 R/W –––––R2CE R1CE LCE 0x1F

Filter Setting 0x06 R/W – – – – R2F1 R2F0 R1F1 R1F0 0x0F

1-shot 0x0F WO – – – – – – – – –

17 www.national.com

LM95213

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Common Status Register 0x02 RO BUSY NR – – SR4F SR3F SR2F SR1F 0x00

Status 1 (Diode Fault) 0x07 RO – – – – R2DO R2DS R1DO R1DS –

Status 2 (TCRIT1) 0x08 RO –––––R2T1 R1T1 LT1 –

Status 3 (TCRIT2) 0x09 RO –––––R2T2 R1T2 LT2 –

Status 4 (TCRIT3) 0x0A RO –––––R2T3 R1T3 LT3 –

TCRIT1 Mask 0x0C R/W –––––R2T1M R1T1M LTM 0x01

TCRIT2 Mask 0x0D R/W –––––R2T2M R1T2M LTM 0x00

TCRIT3 Mask 0x0E R/W –––––R2T2M R1T2M LTM 0x07

Local Tcrit Limit 0x40 R/W 0 64 32 16 8 4 2 1 0x55

Remote 1 Tcrit-1 Limit 0x41 R/W 128 64 32 16 8 4 2 1 0x6E

Remote 2 Tcrit-1 Limit 0x42 R/W 128 64 32 16 8 4 2 1 0x6E

Remote 1 Tcrit-2 and Tcrit-3 Limit 0x49 R/W 128 64 32 16 8 4 2 1 0x55

Remote 2 Tcrit-2 and Tcrit-3 Limit 0x4A R/W 128 64 32 16 8 4 2 1 0x55

Common Tcrit Hysteresis 0x5A R/W 0 0 0 16 8 4 2 1 0x0A

Manufacturer ID 0xFE RO 0 0 0 0 0 0 0 1 0x01

Revision ID 0xFF RO 1 0 0 0 1 0 1 1 0x8B

2.1 VALUE REGISTERS

For data synchronization purposes, the MSB register should be read first if the user wants to read both MSB and LSB registers.

The LSB will be locked after the MSB is read. The LSB will be unlocked after being read. If the user reads MSBs consecutively,

each time the MSB is read, the LSB associated with that temperature will be locked in and override the previous LSB value locked-

2.1.1 Local Value Registers

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Local Temp MSB 0x10 RO SIGN 64 32 16 8 4 2 1 –

Local Temp LSB 0x20 RO 1/2 1/4 1/8 0 0 0 0 0 –

Bit(s) Bit Name Read/

Write

Description

7 SIGN RO Sign bit The Local temperature MSB value

value programmed in this register is used

to determine a local temperature error

event.

6 64 RO bit weight 64°C

5 32 RO bit weight 32°C

4 16 RO bit weight 16°C

3 8 RO bit weight 8°C

2 4 RO bit weight 4°C

1 2 RO bit weight 2°C

0 1 RO bit weight 1°C

Bit(s) Bit Name Read/

Write

Description

7 1/2 RO bit weight 1/2°C (0.5°C) The Local Limit register range is 0°C to

127°C. The value programmed in this

temperature error event.

6 1/4 RO bit weight 1/4°C (0.25°C)

5 1/8 RO bit weight 1/8°C (0.125°C)

4-0 0 RO Reserved – will report "0" when read.

www.national.com 18

LM95213

2.1.2 Remote Temperature Value Registers with Signed Format

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Remote Temp 1 MSB – Signed 0x11 RO SIGN 64 32 16 8 4 2 1 –

Remote Temp 1 LSB – Signed, Digital

Filter Off 0x21 RO 1/2 1/8

0 0

0 0 0 0 –

Remote Temp 1 LSB – Signed, Digital

Filter On 1/16 1/32

Remote Temp 2 MSB – Signed 0x12 RO SIGN 64 32 16 8 4 2 1 –

Remote Temp 2 LSB – Signed, Digital

Filter Off 0x22 RO 1/2 1/8

0 0

0 0 0 0 –

Remote Temp 2 LSB – Signed, Digital

Filter On 1/16 1/32

The Local temperature MSB value register range is +127°C to −128°C. The value programmed in this register is used to determine

a local temperature error event.

Bit(s) Bit Name Read/

Write

Description

7 SIGN RO Sign bit

6 64 RO bit weight 64°C

5 32 RO bit weight 32°C

4 16 RO bit weight 16°C

3 8 RO bit weight 8°C

2 4 RO bit weight 4°C

1 2 RO bit weight 2°C

0 1 RO bit weight 1°C

Bit(s) Bit Name Read/

Write

Description

7 1/2 RO bit weight 1/2°C (0.5°C)

6 1/4 RO bit weight 1/4°C (0.25°C)

5 1/8 RO bit weight 1/8°C (0.125°C)

4 0 or 1/16 RO When the digital filter is disabled this bit will always read "0".

When the digital filter is enabled this bit will report 1/16°C (0.0625°C) bit state.

3 0 or 1/32 RO When the digital filter is disabled this bit will always read "0".

When the digital filter is enabled this bit will report 1/32°C (0.03125°C) bit state.

2-0 0 RO Reserved – will report "0" when read.

19 www.national.com

LM95213

2.1.3 Remote Temperature Value Registers with Unsigned Format

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Remote Temp 1 MSB – Unsigned 0x19 RO 128 64 32 16 8 4 2 1 –

Remote Temp 1 LSB – Unsigned,

Digital Filter Off 0x29 RO 1/2 1/8

0 0

0 0 0 0 –

Remote Temp 1 LSB – Unsigned,

Digital Filter On 1/16 1/32

Remote Temp 2 MSB – Unsigned 0x1A RO 128 64 32 16 8 4 2 1 –

Remote Temp 2 LSB – Unsigned,

Digital Filter Off 0x2A RO 1/2 1/8

0 0

0 0 0 0 –

Remote Temp 2 LSB – Unsigned,

Digital Filter On 1/16 1/32

Bit(s) Bit Name Read/

Write

Description

7 SIGN RO bit weight 128°C

6 64 RO bit weight 64°C

5 32 RO bit weight 32°C

4 16 RO bit weight 16°C

3 8 RO bit weight 8°C

2 4 RO bit weight 4°C

1 2 RO bit weight 2°C

0 1 RO bit weight 1°C

Bit(s) Bit Name Read/

Write

Description

7 1/2 RO bit weight 1/2°C (0.5°C)

6 1/4 RO bit weight 1/4°C (0.25°C)

5 1/8 RO bit weight 1/8°C (0.125°C)

4 0 or 1/16 RO When the digital filter is disabled this bit will always read "0".

When the digital filter is enabled this bit will report 1/16°C (0.0625°C) bit state.

3 0 or 1/32 RO When the digital filter is disabled this bit will always read "0".

When the digital filter is enabled this bit will report 1/32°C (0.03125°C) bit state.

2-0 0 RO Reserved – will report "0" when read.

2.2 DIODE CONFIGURATION REGISTERS

2.2.1 Remote 1-2 Offset

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Remote 1 Offset 0x31 R/W SIGN 32 16 8 4 2 1 1/2 0x00

Remote 2 Offset 0x32 R/W SIGN 32 16 8 4 2 1 1/2 0x00

www.national.com 20

LM95213

Bit(s) Bit Name Read/

Write

Description

7 SIGN R/W Sign bit All registers have 2’s complement format.

The offset range for each remote is

+63.5°C/−64°C. The value programmed

in this register is directly added to the

actual reading of the ADC and the

modified number is reported in the remote

value registers.

6 32 R/W bit weight 32°C

5 16 R/W bit weight 16°C

4 8 R/W bit weight 8°C

3 4 R/W bit weight 4°C

2 2 R/W bit weight 2°C

1 1 R/W bit weight 1°C

0 1/2 R/W bit weight 1/2°C (0.5°C)

2.3 CONFIGURATION REGISTERS

2.3.1 Main Configuration Register

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Configuration 0x03 R/W –STBY – – – – – – 0x00

Bit(s) Bit Name Read/

Write

Description

7–RO Reserved will report "0" when read.

6 STBY R/W Software Standby

1 – standby (when in this mode one conversion sequence can be initiated by writing

to the one-shot register)

0 – active/converting

5–0 –RO Reserved – will report "0" when read.

2.3.2 Conversion Rate Register

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Conversion Rate 0x04 R/W – – – – – – CR1 CR0 0x02

Bit(s) Bit Name Read/

Write

Description

7-2 –RO Reserved – will report "0" when read.

1-0 CR[1:0] R/W Conversion rate control bits modify the time interval for conversion of the channels

enabled. The channels enabled are converted sequentially then standby mode

enabled for the remainder of the time interval.

CR[1:0] Conversion Rate

00 continuous (30 ms to 104 ms)

01 0.364 s

10 1s

11 2.5 s

2.3.3 Channel Conversion Enable

When a conversion is disabled for a particular channel it is skipped. The continuous conversion rate is effected all other conversion

rates are not effected as extra standby time is inserted in order to compensate. See Conversion Rate Register description.

21 www.national.com

LM95213

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Channel Conversion Enable 0x05 R/W –––––R2CE R1CE LCE 0x1F

Bit(s) Bit Name Read/

Write

Description

7–3 –RO Reserved – will report "0" when read.

2 R2CE R/W Remote 2 Temperature Conversion Enable

1– Remote 2 temp conversion enabled

0– Remote 2 temp conversion disabled

1 R1CE R/W Remote 1 Temperature Conversion Enable

1– Remote 1 temp conversion enabled

0– Remote 1 temp conversion disabled

0 LCE R/W Local Temperature Conversion Enable

1– Local temp conversion enabled

0– Local temp conversion disabled

2.3.4 Filter Setting

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Filter Setting 0x06 R/W – – – – R2F1 R2F0 R1F1 R1F0 0x0F

Bit(s) Bit Name Read/

Write

Description

7–4 –RO Reserved – will report "0" when read.

3–2 R2F[1:0] R/W Remote Channel 2 Filter Enable Bits

R2F[1:0] Digital Filter State

00 disable all digital filtering

01 enable basic filter

10 reserved (do not use)

11 enable enhanced filter

1–0 R1F[1:0] R/W Remote Channel 1 Filter Enable

R1F[1:0] Filter State

00 disable all digital filtering

01 enable basic filter

10 reserved (do not use)

11 enable enhanced filter

2.3.5 1-Shot

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

1-Shot 0x0F WO – – – – – – – – –

Bit(s) Bit Name Read/

Write

Description

7–0 - WO Writing to this register activates one conversion for all the enabled channels

if the chip is in standby mode (i.e. standby bit = 1). The actual data written

does not matter and is not stored.

www.national.com 22

LM95213

2.4 STATUS REGISTERS

2.4.1 Common Status Register

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Common Status Register 0x02 RO BUSY NR – – SR4F SR3F SR2F SR1F 0x00

Bit(s) Bit Name Read/

Write

Description

7 BUSY RO Busy bit (device converting)

6 NR RO Not Ready bit (30 ms), indicates power up initialization sequence is in progress

5–4 –RO Reserved – will report "0" when read.

3 SR4F RO Status Register 4 Flag:

1 – indicates that Status Register 4 has at least one bit set

0 – indicates that all of Status Register 4 bits are cleared

2 SR3F RO Status Register 3 Flag:

1 – indicates that Status Register 3 has at least one bit set

0 – indicates that all of Status Register 3 bits are cleared

1 SR2F RO Status Register 2 Flag:

1 – indicates that Status Register 2 has at least one bit set

0 – indicates that all of Status Register 2 bits are cleared

0 SR1F RO Status Register 1 Flag:

1 – indicates that Status Register 1 has at least one bit set

0 – indicates that all of Status Register 1 bits are cleared

2.4.2 Status 1 Register (Diode Fault)

Status fault bits for open or shorted diode (i.e. Short Fault: D+ shorted to Ground or D-; Open Fault: D+ shorted to VDD, or floating).

During fault conditions the temperature reading is 0 °C if unsigned value registers are read or –128.000 °C if signed value registers

are read.

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Status 1 (Diode Fault) 0x07 RO 0 0 0 0 R2DO R2DS R1DO R1DS –

Bit(s) Bit Name Read/

Write

Description

7-4 –RO Reserved – will report "0" when read.

3 R2DO RO Remote 2 diode open fault status:

1 – indicates that remote 2 diode has an "open" fault

0 – indicates that remote 2 diode does not have an "open" fault

2 R2DS RO Remote 2 diode short fault status:

1 – indicates that remote 2 diode has a "short" fault

0 – indicates that remote 2 diode does not have a "short" fault

1 R1DO RO Remote 1 diode open fault status:

1 – indicates that remote 1 diode has an "open" fault

0 – indicates that remote 1 diode does not have an "open" fault

0 R1DS RO Remote 1 diode short fault status:

1 – indicates that remote 1 diode has a "short" fault

0 – indicates that remote 1 diode does not have a "short" fault

23 www.national.com

LM95213

2.4.3 Status 2 (TCRIT1)

Status bits for TCRIT1. When one or more of these bits are set and if not masked the TCRIT1 output will activate. TCRIT1 will

deactivate when all these bits are cleared.

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Status 2 (TCRIT1) 0x08 RO –––––R2T1 R1T1 LT1 –

Bit(s) Bit Name Read/

Write

Description

7–3 - RO Reserved – will report "0" when read.

2 R2T1 RO Remote 2 Tcrit-1 Status:

1 – indicates that remote 2 reading is greater than or equal to the value set in Remote 2

Tcrit-1 Limit register

0 – indicates that that remote 2 reading is less than the value set in Remote 2 Tcrit-1 Limit

1 R1T1 RO Remote 1 Tcrit-1 Status:

1 – indicates that remote 1 reading is greater than or equal to the value set in Remote 1

Tcrit-1 Limit register

0 – indicates that that remote 1 reading is less than the value set in Remote 1 Tcrit-1 Limit

0 LT1 RO Local Tcrit Status:

1 – indicates that local reading is greater than or equal to the value set in Local Tcrit Limit

0 – indicates that local reading is less than the value set in Local Tcrit Limit register minus

the Common Hysteresis value

2.4.4 Status 3 (TCRIT2)

Status bits for TCRIT2. When one or more of these bits are set and if not masked the TCRIT2 output will activate. TCRIT2 will

deactivate when all these bits are cleared.

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Status 3 (TCRIT2) 0x09 RO –––––R2T2 R1T2 LT2 –

Bit(s) Bit Name Read/

Write

Description

7–3 - RO Reserved – will report "0" when read.

2 R2T2 RO Remote 2 Tcrit-2 Status:

1 – indicates that remote 2 reading is greater than or equal to the value set in Remote 2

Tcrit-2 Limit register

0 – indicates that that remote 2 reading is less than the value set in Remote 2 Tcrit-2 Limit

1 R1T2 RO Remote 1 Tcrit-2 Status:

1 – indicates that remote 1 reading is greater than or equal to the value set in Remote 1

Tcrit-2 Limit register

0 – indicates that that remote 1 reading is less than the value set in Remote 1 Tcrit-2 Limit

0 LT2 RO Local Tcrit Status:

1 – indicates that local reading is greater than or equal to the value set in Local Tcrit Limit

0 – indicates that local reading is less than the value set in Local Tcrit Limit register minus

the Common Hysteresis value

www.national.com 24

LM95213

2.4.5 Status 4 (TCRIT3)

Status bits for TCRIT3. When one or more of these bits are set and if not masked the TCRIT3 output will activate. TCRIT3 will

deactivate when all these bits are cleared.

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Status 4 (TCRIT3) 0x0A RO –––––R2T3 R1T3 LT3 –

Bit(s) Bit Name Read/

Write

Description

7–3 - RO Reserved – will report "0" when read.

2 R2T3 RO Remote 2 Tcrit-2 Status:

1 – indicates that remote 2 reading is greater than or equal to the value set in Remote 2

Tcrit-2 Limit register

0 – indicates that that remote 2 reading is less than the value set in Remote 2 Tcrit-2 Limit

1 R1T3 RO Remote 1 Tcrit-2 Status:

1 – indicates that remote 1 reading is greater than or equal to the value set in Remote 1

Tcrit-2 Limit register

0 – indicates that that remote 1 reading is less than the value set in Remote 1 Tcrit-2 Limit

0 LT3 RO Local Tcrit Status:

1 – indicates that local reading is greater than or equal to the value set in Local Tcrit Limit

0 – indicates that local reading is less than the value set in Local Tcrit Limit register minus

the Common Hysteresis value

2.5 MASK REGISTERS

2.5.1 TCRIT1 Mask Register

The mask bits in this register allow control over which error events propagate to the TCRIT1 pin.

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

TCRIT1 Mask 0x0C R/W –––––R2T1

R1T1

LTM 0x01

Bit(s) Bit Name Read/

Write

Description

7-3 –RO Reserved – will report "0" when read.

2 R2T1M R/W Remote 2 Tcrit-1 Mask:

1 – prevents the remote 2 temperature error event from propagating to the TCRIT1 pin

0 – allows the remote 2 temperature error event to propagate to the TCRIT1 pin

1 R1T1M R/W Remote 1 Tcrit-1 Mask:

1 – prevents the remote 1 temperature error event from propagating to the TCRIT1 pin

0 – allows the remote 1 temperature error event to propagate to the TCRIT1 pin

0 LTM R/W Local Tcrit Mask:

1 – prevents the local temperature error event from propagating to the TCRIT1 pin

0 – allows the local temperature error event to propagate to the TCRIT1 pin

25 www.national.com

LM95213

2.5.2 TCRIT2 Mask Registers

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

TCRIT2 Mask 0x0D R/W –––––R2T2

R1T2

LTM 0x00

Bit(s) Bit Name Read/

Write

Description

7-3 –RO Reserved – will report "0" when read.

2 R2T2M R/W Remote 2 Tcrit-2 Mask:

1 – prevents the remote 2 temperature error event from propagating to the TCRIT2 pin

0 – allows the remote 2 temperature error event to propagate to the TCRIT2 pin

1 R1T2M R/W Remote 1 Tcrit-2 Mask:

1 – prevents the remote 1 temperature error event from propagating to the TCRIT2 pin

0 – allows the remote 1 temperature error event to propagate to the TCRIT2 pin

0 LTM R/W Local Tcrit Mask:

1 – prevents the local temperature error event from propagating to the TCRIT2 pin

0 – allows the local temperature error event to propagate to the TCRIT2 pin

2.5.3 TCRIT3 Mask Register

The mask bits in this register allow control over which error events propagate to the TCRIT3 pin.

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

TCRIT3 Mask 0x0E R/W –––––R2T2

R1T2

LTM 0x07

Bit(s) Bit Name Read/

Write

Description

7-3 –RO Reserved – will report "0" when read.

2 R2T2M R/W Remote 2 Tcrit-2 Mask:

1 – prevents the remote 2 temperature error event from propagating to the TCRIT3 pin

0 – allows the remote 2 temperature error event to propagate to the TCRIT3 pin

1 R1T2M R/W Remote 1 Tcrit-2 Mask:

1 – prevents the remote 1 temperature error event from propagating to the TCRIT3 pin

0 – allows the remote 1 temperature error event to propagate to the TCRIT3 pin

0 LTM R/W Local Tcrit Mask:

1 – prevents the local temperature error event from propagating to the TCRIT3 pin

0 – allows the local temperature error event to propagate to the TCRIT3 pin

2.6 LIMIT REGISTERS

2.6.1 Local Limit Register

The Local Limit register range is 0°C to 127°C. The value programmed in this register is used to determine a local temperature

error event.

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Local Tcrit Limit 0x40 R/W 0 64 32 16 8 4 2 1 0x55

www.national.com 26

LM95213

Bit(s) Bit Name Read/

Write

Description

7 0 R0 Read only bit will always report "0".

6 64 R/W bit weight 64°C

5 32 R/W bit weight 32°C

4 16 R/W bit weight 16°C

3 8 R/W bit weight 8°C

2 4 R/W bit weight 4°C

1 2 R/W bit weight 2°C

0 1 R/W bit weight 1°C

2.6.2 Remote Limit Registers

The range for these registers is 0°C to 255°C.

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Remote 1 Tcrit-1 Limit (used by

TCRIT1 error events)

0x41 R/W 128 64 32 16 8 4 2 1 0x6E

Remote 2 Tcrit-1 Limit (used by

TCRIT1 error events)

0x42 R/W 128 64 32 16 8 4 2 1 0x6E

Remote 1 Tcrit-2 and Tcrit3 Limit

(used by TCRIT2 and TCRIT3 error

events)

0x49 R/W 128 64 32 16 8 4 2 1 0x55

Remote 2 Tcrit-2 and Tcrit3 Limit

(used by TCRIT2 and TCRIT3 error

events)

0x4A R/W 128 64 32 16 8 4 2 1 0x55

Bit(s) Bit Name Read/

Write

Description

7 128 R/W bit weight 128°C

6 64 R/W bit weight 64°C

5 32 R/W bit weight 32°C

4 16 R/W bit weight 16°C

3 8 R/W bit weight 8°C

2 4 R/W bit weight 4°C

1 2 R/W bit weight 2°C

0 1 R/W bit weight 1°C

Limit assignments for each TCRIT output pin:

Output Pin Remote 2 Remote 1 Local

TCRIT1 Remote 2 Tcrit-1 Limit Remote 1 Tcrit-1 Limit Local Tcrit Limit

TCRIT2 Remote 2 Tcrit-2 Limit Remote 1 Tcrit-2 Limit Local Tcrit Limit

TCRIT3 Remote 2 Tcrit-2 Limit Remote 1 Tcrit-2 Limit Local Tcrit Limit

2.6.3 Common Tcrit Hysteresis Register

The hysteresis register range is 0°C to 32°C. The value programmed in this register is used to modify all the limit values for

decreasing temperature.

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Common Tcrit Hysteresis 0x5A R/W 0 0 0 16 8 4 2 1 0x0A

27 www.national.com

LM95213

Bit(s) Bit Name Read/

Write

Description

7 0 RO Read only bit will always report "0".

6 0 RO Read only bit will always report "0".

5 0 RO Read only bit will always report "0".

4 16 R/W bit weight 16°C

3 8 R/W bit weight 8°C

2 4 R/W bit weight 4°C

1 2 R/W bit weight 2°C

0 1 R/W bit weight 1°C

2.7 IDENTIFICATION REGISTERS

Byte

(Hex)

Read/

Write

D7 D6 D5 D4 D3 D2 D1 D0 POR

Default

(Hex)

Manufacturer ID 0xFE RO 0 0 0 0 0 0 0 1 0x01

Revision ID 0xFF RO 1 0 0 0 1 0 1 1 0x8B

www.national.com 28

LM95213

3.0 Applications Hints

The LM95213 can be applied easily in the same way as other

integrated-circuit temperature sensors, and its remote diode

sensing capability allows it to be used in new ways as well. It

can be soldered to a printed circuit board, and because the

path of best thermal conductivity is between the die and the

pins, its temperature will effectively be that of the printed cir-

cuit board lands and traces soldered to the LM95213's pins.

This presumes that the ambient air temperature is almost the

same as the surface temperature of the printed circuit board;

if the air temperature is much higher or lower than the surface

temperature, the actual temperature of the LM95213 die will

be at an intermediate temperature between the surface and

air temperatures. Again, the primary thermal conduction path

is through the leads, so the circuit board temperature will con-

tribute to the die temperature much more strongly than will the

air temperature.

To measure temperature external to the LM95213's die, in-

corporates remote diode sensing technology. This diode can

be located on the die of a target IC, allowing measurement of

the IC's temperature, independent of the LM95213's temper-

ature. A discrete diode can also be used to sense the tem-

perature of external objects or ambient air. Remember that a

discrete diode's temperature will be affected, and often dom-

inated, by the temperature of its leads. Most silicon diodes do

not lend themselves well to this application. It is recommend-

ed that an MMBT3904 transistor base emitter junction be

used with the collector tied to the base.

The LM95213 can measure a diode-connected transistor

such as the MMBT3904 or the thermal diode found in an AMD

processor or FPGA. The LM95213 has been optimized to

measure the remote thermal diode integrated in a typical

MMBT3904 transistor. The offset register can be used to cal-

ibrate for other thermal diodes easily. The LM9513 deos not

include TruTherm™ technology that allows sensing of sub-

micron geometry process thermal diodes. For this applicaiton

the LM95233 would be better suitted.

The LM95233 has been specifically optimized to measure the

remote thermal diode integrated in a typical Intel™ processor

on 65nm or 90 nm process or an MMBT3904 transistor. Using

the Remote Diode Model Select register found in the

LM95233 any of the two remote inputs can be optimized for

a typical Intel processor on 65nm or 90nm process or an

MMBT3904.

3.1 DIODE NON-IDEALITY

3.1.1 Diode Non-Ideality Factor Effect on Accuracy

When a transistor is connected as a diode, the following re-

lationship holds for variables VBE, T and IF:

(1)

where:

•q = 1.6×10−19 Coulombs (the electron charge),

•T = Absolute Temperature in Kelvin

•k = 1.38×10−23 joules/K (Boltzmann's constant),

•η is the non-ideality factor of the process the diode is

manufactured on,

•IS = Saturation Current and is process dependent,

•If = Forward Current through the base-emitter junction

•VBE = Base-Emitter Voltage drop

In the active region, the -1 term is negligible and may be elim-

inated, yielding the following equation

(2)

In Equation 2, η and IS are dependant upon the process that

was used in the fabrication of the particular diode. By forcing

two currents with a very controlled ratio(IF2 / IF1) and measur-

ing the resulting voltage difference, it is possible to eliminate

the IS term. Solving for the forward voltage difference yields

the relationship:

(3)

Solving Equation 3 for temperature yields:

(4)

Equation 4 holds true when a diode connected transistor such

as the MMBT3904 is used. When this “diode” equation is ap-

plied to an integrated diode such as a processor transistor

with its collector tied to GND as shown in Figure 8 it will yield

a wide non-ideality spread. This wide non-ideality spread is

not due to true process variation but due to the fact that

Equation 4 is an approximation.

National invented TruTherm beta cancellation technology us-

es the transistor equation, Equation 5, which is a more accu-

rate representation of the topology of the thermal diode found

in some sub-micron FPGAs or processors.

(5)

29 www.national.com

LM95213

30013815

FIGURE 8. Thermal Diode Current Paths

TruTherm technology can be found in the LM95233 two chan-

nel remote diode sensor that is pin and register compatible

with the LM95213. The LM95213 does ot support this tech-

nology.

3.1.2 Calculating Total System Accuracy

The voltage seen by the LM95213 also includes the IFRS volt-

age drop of the series resistance. The non-ideality factor, η,

is the only other parameter not accounted for and depends

on the diode that is used for measurement. Since ΔVBE is

proportional to both η and T, the variations in η cannot be

distinguished from variations in temperature. Since the non-

ideality factor is not controlled by the temperature sensor, it

will directly add to the inaccuracy of the sensor. For the for

Intel processor on 65 nm process, Intel specifies a +4.06%/

−0.897% variation in η from part to part when the processor

diode is measured by a circuit that assumes diode equation,

Equation 4, as true. As an example, assume a temperature

sensor has an accuracy specification of ±1.0°C at a temper-

ature of 80°C (353 Kelvin) and the processor diode has a non-

ideality variation of +1.19%/−0.27%. The resulting system

accuracy of the processor temperature being sensed will be:

TACC = + 1.0°C + (+4.06% of 353 K) = +15.3 °C

and

TACC = - 1.0°C + (−0.89% of 353 K) = −4.1 °C

The next error term to be discussed is that due to the series

resistance of the thermal diode and printed circuit board

traces. The thermal diode series resistance is specified on

most processor data sheets. For Intel processors in 65 nm

process, this is specified at 4.52Ω typical. The LM95213 ac-

commodates the typical series resistance of Intel Processor

on 65 nm process. The error that is not accounted for is the

spread of the processor's series resistance, that is 2.79Ω to

6.24Ω or ±1.73Ω. The equation to calculate the temperature

error due to series resistance (TER) for the LM95213 is simply:

(6)

Solving Equation 6 for RPCB equal to ±1.73Ω results in the

additional error due to the spread in the series resistance of

±1.07°C. The spread in error cannot be canceled out, as it

would require measuring each individual thermal diode de-

vice. This is quite difficult and impractical in a large volume

production environment.

Equation 6 can also be used to calculate the additional error

caused by series resistance on the printed circuit board. Since

the variation of the PCB series resistance is minimal, the bulk

of the error term is always positive and can simply be can-

celled out by subtracting it from the output readings of the

LM95213.

Processor Family Diode Equation ηD, non-

ideality

Series

R,Ω

min typ max

Pentium™ III

CPUID 67h 1 1.0065 1.0125

Pentium III CPUID

68h/

PGA370Socket/

Celeron

1.0057 1.008 1.0125

Pentium 4, 423 pin 0.9933 1.0045 1.0368

Pentium 4, 478 pin 0.9933 1.0045 1.0368

Pentium 4 on 0.13

micron process, 2 -

3.06 GHz

1.0011 1.0021 1.0030 3.64

Pentium 4 on 90 nm

process 1.0083 1.011 1.023 3.33

Intel Processor on

65 nm process 1.000 1.009 1.050 4.52

Pentium M

(Centrino) 1.00151 1.00220 1.00289 3.06

MMBT3904 1.003

AMD Athlon MP

model 6 1.002 1.008 1.016

AMD Athlon 64 1.008 1.008 1.096

AMD Opteron 1.008 1.008 1.096

AMD Sempron 1.00261 0.93

3.1.3 Compensating for Different Non-Ideality

In order to compensate for the errors introduced by non-ide-

ality, the temperature sensor is calibrated for a particular

www.national.com 30

LM95213

processor. National Semiconductor temperature sensors are

always calibrated to the typical non-ideality and series resis-

tance of a given processor type. The LM95213 is calibrated

for non-ideality factor and series resistance values supporting

the MMBT3904 transistor without the requirement for addi-

tional trims. When a temperature sensor calibrated for a

particular processor type is used with a different processor

type, additional errors are introduced.

Temperature errors associated with non-ideality of different

processor types may be reduced in a specific temperature

range of concern through use of software calibration. Typical

Non-ideality specification differences cause a gain variation

of the transfer function, therefore the center of the tempera-

ture range of interest should be the target temperature for

calibration purposes. The following equation can be used to

calculate the temperature correction factor (TCF) required to

compensate for a target non-ideality differing from that sup-

ported by the LM95213.

(7)

where

•ηS = LM95213 non-ideality for accuracy specification

•ηPROCESSOR = Processor thermal diode typical non-ideality

•TCR = center of the temperature range of interest in °C

The correction factor should be directly added to the temper-

ature reading produced by the LM95213. For example when

using the LM95213 to measure a AMD Athlon processor, with

a typical non-ideality of 1.008, for a temperature range of 60

°C to 100 °C the correction factor would calculate to:

(8)

Therefore, 1.75°C should be subtracted from the temperature

readings of the LM95213 to compensate for the differing typ-

ical non-ideality target.

3.2 PCB LAYOUT FOR MINIMIZING NOISE

30013817

FIGURE 9. Ideal Diode Trace Layout

In a noisy environment, such as a processor mother board,

layout considerations are very critical. Noise induced on

traces running between the remote temperature diode sensor

and the LM95213 can cause temperature conversion errors.

Keep in mind that the signal level the LM95213 is trying to

measure is in microvolts. The following guidelines should be

followed:

1. VDD should be bypassed with a 0.1 µF capacitor in

parallel with 100 pF. The 100 pF capacitor should be

placed as close as possible to the power supply pin. A

bulk capacitance of approximately 10 µF needs to be in

the near vicinity of the LM95213.

2. A 100 pF diode bypass capacitor is recommended to filter

high frequency noise but may not be necessary. Make

sure the traces to the 100 pF capacitor are matched.

Place the filter capacitors close to the LM95213 pins.

3. Ideally, the LM95213 should be placed within 10 cm of

the Processor diode pins with the traces being as

straight, short and identical as possible. Trace resistance

of 1Ω can cause as much as 0.62°C of error. This error

can be compensated by using simple software offset

compensation.

4. Diode traces should be surrounded by a GND guard ring

to either side, above and below if possible. This GND

guard should not be between the D+ and D− lines. In the

event that noise does couple to the diode lines it would

be ideal if it is coupled common mode. That is equally to

the D+ and D− lines.

5. Avoid routing diode traces in close proximity to power

supply switching or filtering inductors.

6. Avoid running diode traces close to or parallel to high

speed digital and bus lines. Diode traces should be kept

at least 2 cm apart from the high speed digital traces.

7. If it is necessary to cross high speed digital traces, the

diode traces and the high speed digital traces should

cross at a 90 degree angle.

8. The ideal place to connect the LM95213's GND pin is as

close as possible to the Processors GND associated with

the sense diode.

9. Leakage current between D+ and GND and between D+

and D− should be kept to a minimum. Thirteen nano-

amperes of leakage can cause as much as 0.2°C of error

in the diode temperature reading. Keeping the printed

circuit board as clean as possible will minimize leakage

current.

Noise coupling into the digital lines greater than 400 mVp-p

(typical hysteresis) and undershoot less than 500 mV below

GND, may prevent successful SMBus communication with

the LM95213. SMBus no acknowledge is the most common

symptom, causing unnecessary traffic on the bus. Although

the SMBus maximum frequency of communication is rather

low (100 kHz max), care still needs to be taken to ensure

proper termination within a system with multiple parts on the

bus and long printed circuit board traces. An RC lowpass filter

with a 3 dB corner frequency of about 40 MHz is included on

the LM95213's SMBCLK input. Additional resistance can be

added in series with the SMBDAT and SMBCLK lines to fur-

ther help filter noise and ringing. Minimize noise coupling by

keeping digital traces out of switching power supply areas as

well as ensuring that digital lines containing high speed data

communications cross at right angles to the SMBDAT and

SMBCLK lines.

31 www.national.com

LM95213

Physical Dimensions inches (millimeters) unless otherwise noted

14-Lead Molded Leadless Leadframe Package (LLP),

Order Number LM95213CISD or LM95213CISDX

NS Package Number SDA14B

www.national.com 32

LM95213

Notes

33 www.national.com

LM95213

Notes

LM95213 2-Diode Input and Local Digital Temperature Sensor with Two-Wire Interface and

TCRIT Outputs

THE CONTENTS OF THIS DOCUMENT ARE PROVIDED IN CONNECTION WITH NATIONAL SEMICONDUCTOR CORPORATION

(“NATIONAL”) PRODUCTS. NATIONAL MAKES NO REPRESENTATIONS OR WARRANTIES WITH RESPECT TO THE ACCURACY

OR COMPLETENESS OF THE CONTENTS OF THIS PUBLICATION AND RESERVES THE RIGHT TO MAKE CHANGES TO

SPECIFICATIONS AND PRODUCT DESCRIPTIONS AT ANY TIME WITHOUT NOTICE. NO LICENSE, WHETHER EXPRESS,

IMPLIED, ARISING BY ESTOPPEL OR OTHERWISE, TO ANY INTELLECTUAL PROPERTY RIGHTS IS GRANTED BY THIS

DOCUMENT.

TESTING AND OTHER QUALITY CONTROLS ARE USED TO THE EXTENT NATIONAL DEEMS NECESSARY TO SUPPORT

NATIONAL’S PRODUCT WARRANTY. EXCEPT WHERE MANDATED BY GOVERNMENT REQUIREMENTS, TESTING OF ALL

PARAMETERS OF EACH PRODUCT IS NOT NECESSARILY PERFORMED. NATIONAL ASSUMES NO LIABILITY FOR

APPLICATIONS ASSISTANCE OR BUYER PRODUCT DESIGN. BUYERS ARE RESPONSIBLE FOR THEIR PRODUCTS AND

APPLICATIONS USING NATIONAL COMPONENTS. PRIOR TO USING OR DISTRIBUTING ANY PRODUCTS THAT INCLUDE

NATIONAL COMPONENTS, BUYERS SHOULD PROVIDE ADEQUATE DESIGN, TESTING AND OPERATING SAFEGUARDS.

EXCEPT AS PROVIDED IN NATIONAL’S TERMS AND CONDITIONS OF SALE FOR SUCH PRODUCTS, NATIONAL ASSUMES NO

LIABILITY WHATSOEVER, AND NATIONAL DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY RELATING TO THE SALE

AND/OR USE OF NATIONAL PRODUCTS INCLUDING LIABILITY OR WARRANTIES RELATING TO FITNESS FOR A PARTICULAR

PURPOSE, MERCHANTABILITY, OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY

RIGHT.

LIFE SUPPORT POLICY

NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR

SYSTEMS WITHOUT THE EXPRESS PRIOR WRITTEN APPROVAL OF THE CHIEF EXECUTIVE OFFICER AND GENERAL

COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:

Life support devices or systems are devices which (a) are intended for surgical implant into the body, or (b) support or sustain life and

whose failure to perform when properly used in accordance with instructions for use provided in the labeling can be reasonably expected

to result in a significant injury to the user. A critical component is any component in a life support device or system whose failure to perform

can be reasonably expected to cause the failure of the life support device or system or to affect its safety or effectiveness.

National Semiconductor and the National Semiconductor logo are registered trademarks of National Semiconductor Corporation. All other

brand or product names may be trademarks or registered trademarks of their respective holders.

For the most current product information visit us at www.national.com

National Semiconductor

Americas Customer

Support Center

Email:

new.feedback@nsc.com

Tel: 1-800-272-9959

National Semiconductor Europe

Customer Support Center

Fax: +49 (0) 180-530-85-86

Email: europe.support@nsc.com

Deutsch Tel: +49 (0) 69 9508 6208

English Tel: +49 (0) 870 24 0 2171

Français Tel: +33 (0) 1 41 91 8790

National Semiconductor Asia

Pacific Customer Support Center

Email: ap.support@nsc.com

National Semiconductor Japan

Customer Support Center

Fax: 81-3-5639-7507

Email: jpn.feedback@nsc.com

Tel: 81-3-5639-7560