TI LMT70AYFQT Precision analog temperature sensor, rtd and precision ntc thermistor ic Datasheet

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LMT70, LMT70A
SNIS187A – MARCH 2015 – REVISED JULY 2015
LMT70, LMT70A ±0.05°C Precision Analog Temperature Sensor, RTD and Precision NTC
Thermistor IC
1 Features
3 Description
•
The LMT70 is an ultra-small, high-precision, lowpower CMOS analog temperature sensor with an
output enable pin. Applications for the LMT70 include
virtually any type of temperature sensing where costeffective, high precision and low-power are required,
such as Internet of Things (IoT) sensor nodes,
medical thermometers, high-precision instrumentation
and battery powered devices. The LMT70 is also a
great replacement for RTD and precision NTC/PTC
thermistors.
1
•
•
•
•
•
•
•
•
Accuracy:
– ±0.05°C (typ) or ±0.13°C (max) from 20°C to
42°C
– ±0.2°C (max) from -20°C to 90°C
– ±0.23°C (max) from 90°C to 110°C
– ±0.36°C (max) from -55°C to 150°C
Wide Temperature Range: −55°C to 150°C
Matching of Two Adjacent LMT70A on Tape and
Reel: 0.1°C (max) at 30°C
Very Linear Analog Temperature Sensor with
Output Enable Pin
NTC Output Slope: -5.19 mV/°C
Output On/Off Switch with RDS on < 80 Ω
Wide Power Supply Range: 2.0 V to 5.5 V
Low Power Supply Current: 9.2 µA (typ)12 µA
(max)
Ultra Small 0.88 mm by 0.88 mm 4-bump WLCSP
(DSBGA) Package
2 Applications
•
•
•
•
•
•
Internet of Things (IoT) Sensor Nodes
Industrial RTD (Class AA) or Precision NTC/PTC
Thermistor Replacement
Medical/Fitness Equipment
Medical Thermometer
Human Body temperature monitor
Metering Temperature Compensation
Its output enable pin allows multiple LMT70s to share
one ADC channel, thus simplifying ADC calibration
and reducing the overall system cost for precision
temperature sensing. The LMT70 also has a linear
and low impedance output allowing seamless
interface to an off-the-shelf MCU/ADC. Dissipating
less than 36µW, the LMT70 has ultra-low self-heating
supporting its high-precision over a wide temperature
range.
The LMT70A provides unparalleled temperature
matching performance of 0.1°C (max) for two
adjacent LMT70A's picked from the same tape and
reel. Therefore, the LMT70A is an ideal solution for
energy metering applications requiring heat transfer
calculations.
Device Information (1)
PART NUMBER
LMT70
(1)
PACKAGE
BODY SIZE (NOM)
DSBGA - WLCSP (4)
YFQ
0.88 mm x 0.88 mm
For all available packages, see the orderable addendum at
the end of the data sheet.
4 Wide-Range Precision Active RTD or NTC Replacement (−55°C to 150°C)
LMT70 Accuracy vs Temperature
0.60
Coin Cell
Battery
0.50
0.40
2.2V to 3.6V
Max Limit
GPIO1
MSP430
GPIO2
P2.5_VREF
VDD
0.10
0.00
-0.10
-0.20
Min Limit
-0.40
-0.50
P2.3
TAO
0.20
-0.30
1.5V
Vref
T_ON
LMT70
Accuracy (C)
0.30
M
U
X
ADC
(12-bit)
-0.60
±60 ±40 ±20
0
20
40
60
80
DUT Temperature (C)
100 120 140 160
C001
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
LMT70, LMT70A
SNIS187A – MARCH 2015 – REVISED JULY 2015
www.ti.com
Table of Contents
1
2
3
4
5
6
7
8
Features ..................................................................
Applications ...........................................................
Description .............................................................
Wide-Range Precision Active RTD or NTC
Replacement (−55°C to 150°C) .............................
Revision History.....................................................
Device Comparison Table.....................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
10 Application and Implementation........................ 16
1
2
3
3
4
8.1
8.2
8.3
8.4
8.5
8.6
Absolute Maximum Ratings ...................................... 4
ESD Ratings.............................................................. 4
Recommended Operating Conditions....................... 4
Thermal Information .................................................. 4
Electrical Characteristics........................................... 5
Electrical Characteristics Temperature Lookup Table
(LUT) .......................................................................... 6
8.7 Switching Characteristics .......................................... 7
8.8 Typical Performance Characteristics ....................... 7
9
9.2 Functional Block Diagram ....................................... 11
9.3 Feature Description................................................. 11
9.4 Device Functional Modes........................................ 15
Detailed Description ............................................ 11
9.1 Overview ................................................................. 11
10.1 Application Information.......................................... 16
10.2 Typical Application ................................................ 16
10.3 System Examples ................................................. 21
11 Power Supply Recommendations ..................... 21
12 Layout................................................................... 22
12.1 Layout Guidelines ................................................. 22
12.2 Layout Example .................................................... 22
13 Device and Documentation Support ................. 23
13.1
13.2
13.3
13.4
13.5
13.6
Related Links ........................................................
Documentation Support .......................................
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
23
23
23
23
23
23
14 Mechanical, Packaging, and Orderable
Information ........................................................... 23
5 Revision History
Changes from Original (March 2015) to Revision A
Page
•
Added typical accuracy specification...................................................................................................................................... 1
•
Expanded range for ±0.2°C accuracy from "20°C to 90°C" to "-20°C to 90°C". .................................................................... 1
•
Added 9.2µA (typ). ................................................................................................................................................................. 1
•
Updated schematic ................................................................................................................................................................. 3
•
Added -20°C accuracy specification ...................................................................................................................................... 5
•
Changed from 20°C to 20°C to 42°C for accuracy specification condition ........................................................................... 5
•
Added 50°C accuracy specification ....................................................................................................................................... 5
•
Added typical supply current specification.............................................................................................................................. 6
•
Changed from 942.547 to 942.552......................................................................................................................................... 6
•
Changed from 943.907 to 943.902......................................................................................................................................... 6
•
Changed from 890.423 to 890.500......................................................................................................................................... 6
•
Changed from 891.934 to 891.857......................................................................................................................................... 6
•
Added -20°C histogram curve ................................................................................................................................................ 8
•
Removed erroneous 10°C histogram ..................................................................................................................................... 8
•
Changed y axis units from (V) to (mV) ................................................................................................................................... 9
•
Added Output Noise vs Frequency curve............................................................................................................................. 10
2
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6 Device Comparison Table
Matching Specification Provided (1)
Order Number
LMT70YFQR, LMT70YFQT
No
LMT70AYFQR, LMT70AYFQT
(1)
Yes, 0.1°C at approximately 30°C (1)
In order to meet the matching specification of the LMT70A, two units
must be picked from adjacent positions from one tape and reel. If
PCB rework is required, involving the LMT70A, then the pair of the
LMT70A matched units must be replaced. Matching features (which
include, without limitation, electrical matching characteristics of
adjacent Components as they are delivered in original packaging
from TI) are warranted solely to the extent that the purchaser can
demonstrate to TI’s satisfaction that the particular Component(s) at
issue were adjacent in original packaging as delivered by TI.
Customers should be advised that the small size of these
Components means they are not individually traceable at the unit
level and it may be difficult to establish the original position of the
Components once they have been removed from that original
packaging as delivered by TI.
7 Pin Configuration and Functions
DSBGA or WLCSP
4 Pins YFQ
(Top View)
GND
(A1)
VDD
(A2)
LMT70
TAO
(B1)
T_ON
(B2)
Pin Functions
PIN
NAME
NO.
TYPE
GND
A1
Ground
VDD
A2
Power
EQUIVALENT CIRCUIT
DESCRIPTION
Ground reference for the device
Supply voltage
VDD
VSENSE
TAO
B1
T_ON
Analog
Output
Temperature analog output pin
T_ON
GND
VDD
T_ON
B2
T_ON pin. Active High input.
If T_ON = 0, then the TAO output is open.
If T_ON = 1, then TAO pin is connected to the temperature output voltage.
Tie this pin to VDD if not used.
Digital Input
GND
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8 Specifications
8.1 Absolute Maximum Ratings (1) (2)
MIN
MAX
UNIT
Supply voltage
−0.3
6
V
Voltage at T_ON and TAO
−0.3
6
V
5
mA
150
°C
Current at any pin
Storage temperature, Tstg
(1)
(2)
-65
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
Soldering process must comply with Reflow Temperature Profile specifications. Refer to www.ti.com/packaging.
8.2 ESD Ratings
VALUE
V(ESD)
(1)
(2)
Electrostatic discharge
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001 (1)
±2000
Charged-device model (CDM), per JEDEC specification JESD22C101 (2)
±750
UNIT
V
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
8.3 Recommended Operating Conditions
MAX
UNIT
Specified temperature (TMIN ≤ TA ≤ TMAX)
MIN
−55
NOM
150
°C
Supply voltage
2.0
5.5
V
8.4 Thermal Information
LMT70
DSBGA or
WLCSP
THERMAL METRIC (1)
UNIT
YFQ 4 PINS
RθJA
Junction-to-ambient thermal resistance
RθJC(top)
Junction-to-case (top) thermal resistance
2.3
RθJB
Junction-to-board thermal resistance
105
ψJT
Junction-to-top characterization parameter
10.9
ψJB
Junction-to-board characterization parameter
104
Thermal response time to 63% of final value in stirred oil (dominated by PCB see
layout)
1.5
sec
Thermal response time to 63% of final value in still air (dominated by PCB see
layout)
73
sec
(1)
4
187
°C/W
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
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8.5 Electrical Characteristics
Limits apply for TA = TJ = TMIN to TMAX and VDD of 2.00V to 5.5V and VDD ≥ VTAO + 1V, unless otherwise noted.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
TEMPERATURE ACCURACY
TAO accuracy
(These stated accuracy limits
are with reference to the values
in Electrical Characteristics
Temperature Lookup Table
(LUT), LMT70 temperature-tovoltage.) (1)
ATC
APSS
VTAO
TA = –55°C
VDD = 2.7 V
-0.33
0.33
TA = –40°C
VDD = 2.7 V
–0.27
0.27
TA = –20°C
VDD = 2.7 V
–0.2
0.2
TA = –10°C
VDD = 2.7 V
–0.18
TA = 20°C to 42°C
VDD = 2.7 V
–0.13
TA = 50°C
VDD = 2.7 V
-0.15
0.15
TA = 90°C
VDD = 2.7 V
–0.20
0.20
TA = 110°C
VDD = 2.7 V
–0.23
0.23
TA = 150°C
VDD = 2.7 V
–0.36
0.36
-2.6
+2.6
Accuracy temperature
VDD = 2.7V
coefficient (note, uses end point
(2)
calculations)
–55°C ≤ TA ≤ 10°C
VDD = VTAO + 1.1 V
to 4.0 V
Accuracy power supply
sensitivity (note uses end point
calculations)
10°C ≤ TA ≤ 120°C
VDD = 2.0 V to 4.0
V
120°C ≤ TA ≤
150°C
VDD = 2.0 V to 4.0
V
–15
VDD = 4 V to 5.5 V
–30
Output Voltage
TA = 30°C
VDD = 2.7 V
TA approximately
30°C
VDD = 2.0 V to 3.6 V
–9
Time stability (4)
–2
0.13
m°C/°C
8
8
–12
0
943.227
mV
–5.194
mV/°C
0.1
TA = 30°C to
150°C
TA = 20°C to 30°C
°C
m°C /V
Sensor gain
Matching of two adjacent parts
in tape and reel for
LMT70AYFQR, LMT70AYFQT
only (see curve Figure 19 for
specification at other
temperatures) (3) (2)
0.18
±0.05
°C
2.5
m°C /°C
0.1
°C
0
0.4
mV
-0.4
0
mV
VDD = 2.0 V to 3.6 V
-2.5
TA = -55°C to 30°C VDD = 2.7 V to 3.6 V
–2.5
10k hours at 90°C
–0.1
±0.01
ANALOG OUTPUT
Operating output voltage
change with load current
ROUT
0 µA≤IL≤5 µA
-5 µA≤IL≤0 µA
Output Resistance
TAO Off Leakage Current
VTAO ≤ VDD – 0.6v, VT_ON=GND
VTAO ≥ 0.2V, VT_ON = GND
Output Load Capacitance
(1)
(2)
(3)
(4)
-0.5
28
80
Ω
0.005
0.5
µA
1100
pF
-0.005
Accuracy is defined as the error between the measured and reference output voltages, tabulated in the Conversion Table at the
specified conditions of supply voltage and temperature (expressed in °C). These stated accuracy limits are with reference to the values
in Electrical Characteristics Temperature Lookup Table (LUT), see Accuracy Curve for other temperatures. Accuracy limits do not
include load regulation or aging; they assume no DC load.
The accuracy temperature coefficient specification is given to indicate part to part performance and does not correlate to the limits given
in the curve Figure 3.
In order to meet the matching specification of the LMT70A, two units must be picked from adjacent positions from one tape and reel. If
PCB rework is required, involving the LMT70A, then the pair of the LMT70A matched units must be replaced. Matching features (which
include, without limitation, electrical matching characteristics of adjacent Components as they are delivered in original packaging from
TI) are warranted solely to the extent that the purchaser can demonstrate to TI’s satisfaction that the particular Component(s) at issue
were adjacent in original packaging as delivered by TI. Customers should be advised that the small size of these Components means
they are not individually traceable at the unit level and it may be difficult to establish the original position of the Components once they
have been removed from that original packaging as delivered by TI.
Determined using accelerated operational life testing at 150°C junction temperature; not tested during production.
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Electrical Characteristics (continued)
Limits apply for TA = TJ = TMIN to TMAX and VDD of 2.00V to 5.5V and VDD ≥ VTAO + 1V, unless otherwise noted.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
POWER SUPPLY
VDO
Dropout Voltage (VDD-VTAO) (5)
–20°C ≤ TA ≤ 20°C
1.0
–55°C ≤ TA ≤ –20°C
1.1
Power Supply Current
V
9.2
VDD ≤ 0.4V (-55°C to +110°C)
Shutdown Current
VDD ≤ 0.4V (+110°C to +150°C)
12
µA
50
nA
350
nA
LOGIC INPUT
T_ON Logic Low Input
Threshold
-55°C to +150°C
T_ON Logic High Input
Threshold
-55°C to +150°C
T_ON Input Current
VT_ON = VDD
0.5
VT_ON = GND
(5)
-1
0.33*VDD
V
0.66*VDD
VDD-0.5
V
0.15
1
µA
-0.02
Dropout voltage (VDO) is defined as the smallest possible differential voltage measured between VTAO and VDD that causes the
temperature error to degrade by 0.02°C.
8.6 Electrical Characteristics Temperature Lookup Table (LUT)
applies for VDD of 2.7V
TEMPERATURE (°C)
6
VTAO (mV)
LOCAL SLOPE (mV/°C)
MIN
TYP
MAX
-55
1373.576
1375.219
1376.862
-4.958
-50
1348.990
1350.441
1351.892
-4.976
-40
1299.270
1300.593
1301.917
-5.002
-30
1249.242
1250.398
1251.555
-5.036
-20
1198.858
1199.884
1200.910
-5.066
-10
1148.145
1149.070
1149.995
-5.108
0
1097.151
1097.987
1098.823
-5.121
10
1045.900
1046.647
1047.394
-5.134
20
994.367
995.050
995.734
-5.171
30
942.547
943.227
943.902
-5.194
40
890.500
891.178
891.857
-5.217
50
838.097
838.882
839.668
-5.241
60
785.509
786.360
787.210
-5.264
70
732.696
733.608
734.520
-5.285
80
679.672
680.654
681.636
-5.306
90
626.435
627.490
628.545
-5.327
100
572.940
574.117
575.293
-5.347
110
519.312
520.551
521.789
-5.368
120
465.410
466.760
468.110
-5.391
130
411.288
412.739
414.189
-5.430
140
356.458
358.164
359.871
-5.498
150
300.815
302.785
304.756
-5.538
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8.7 Switching Characteristics
Limits apply for TA = TJ = TMIN to TMAX and VDD of 2.00V to 5.5V and VDD ≥ VTAO + 1V, unless otherwise noted.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
tPOWER
Power-on Time to 99% of final
voltage value
CL=0 pF to 1100 pF; VDD
connected T_ON
0.6
1
ms
tT_ON
T_ON Time to 99% of final voltage
value (note dependent on RON and
C load)
CL=150pF
30
500
µs
CT_ON
T_ON Digital Input Capacitance
2.2
pF
0.66xVDD
T_ON
tT_ON
99%
TAO
Figure 1. Definition of tT_ON
2V
VDD
tPOWER
99%
TAO
Figure 2. Definition of tPOWER
8.8 Typical Performance Characteristics
0.60
0.50
0.40
0.30
0.33°C
Max Limit
0.20
Frequency
Accuracy (C)
-0.33°C
Min Limit
Max Limit
0.10
0.00
-0.10
-0.20
-0.30
Min Limit
-0.40
-0.50
-0.60
±60 ±40 ±20
0
20
40
60
80
100 120 140 160
DUT Temperature (C)
-0.5
0
Accuracy (C)
C001
VDD=2.7V
using LUT (Look-Up Table) and linear interporlation for conversion
of voltage to temperature
Figure 3. Temperature Accuracy
+0.5
C005
VDD=2.7V
using LUT table for conversion of voltage to temperature
Figure 4. Accuracy Histogram at -55°C
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Typical Performance Characteristics (continued)
-0.27°C
Min Limit
0.27°C
Max Limit
0.2°C
Max Limit
Frequency
Frequency
-0.2°C
Min Limit
-0.5
0
Accuracy (C)
+0.5
-0.5
VDD=2.7V
using LUT table for conversion of voltage to temperature
Figure 6. Accuracy Histogram at –20°C
Figure 5. Accuracy Histogram at -40°C
0.18°C
Max Limit
-0.13°C
Min Limit
+0.5
0
Accuracy (C)
-0.5
C002
VDD=2.7V
using LUT table for conversion of voltage to temperature
Figure 7. Accuracy Histogram at -10°C
Figure 8. Accuracy Histogram at 30°C
0.15°C
Max Limit
0.2°C
Max Limit
-0.2°C
Min Limit
Frequency
Frequency
-0.15°C
Min Limit
+0.5
0
Accuracy (C)
C002
VDD=2.7V
using LUT table for conversion of voltage to temperature
+0.5
0
Accuracy (C)
-0.5
0
Accuracy (C)
C006
VDD=2.7V
using LUT table for conversion of voltage to temperature
Figure 9. Accuracy Histogram at 50°C
8
0.13°C
Max Limit
Frequency
Frequency
-0.5
-0.5
C024
C003
VDD=2.7V
using LUT table for conversion of voltage to temperature
-0.18°C
Min Limit
+0.5
0
Accuracy (C)
+0.5
C007
VDD=2.7V
using LUT table for conversion of voltage to temperature
Figure 10. Accuracy Histogram at 90°C
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Typical Performance Characteristics (continued)
-0.23°C
Min
Limit
-0.26°C
0.26°C
Min Limit Max Limit
Frequency
Frequency
0.23°C
Max
Limit
-0.5
0
Accuracy (C)
+0.5
-0.5
0
Accuracy (C)
C008
VDD=2.7V
using LUT table for conversion of voltage to temperature
+0.5
C009
VDD=2.7V
using LUT table for conversion of voltage to temperature
Figure 11. Accuracy Histogram at 110°C
Figure 12. Accuracy Histogram at 120°C
-4.8
-4.9
0.36°C
Max Limit
-5.0
Frequency
TAO Slope mV/C)
-0.36°C
Min Limit
-5.1
-5.2
-5.3
-5.4
-5.5
-5.6
-5.7
-5.8
-0.5
0
Accuracy (C)
+0.5
±60 ±40 ±20
0
20
40
60
80
100 120 140 160
DUT Temperature (C)
C010
VDD=2.7V
using LUT table for conversion of voltage to temperature
C013
VDD=2.7V
Figure 13. Accuracy Histogram at 150°C
Figure 14. TAO first order transfer function slope vs
temperature
944.0
10.0
9.6
943.5
9.4
VTAO (mV)
Power Supply Current (A)
9.8
9.2
VDD=5.5V
VDD=5V
VDD=4V
VDD=3.6V
VDD=3.3V
VDD=2.7V
VDD=2.4V
VDD=2.2V
VDD=2V
9.0
8.8
8.6
8.4
8.2
8.0
±60 ±40 ±20
0
20
40
60
80
942.5
942.0
100 120 140 160
DUT Temperature (C)
943.0
2.0
C011
2.5
3.0
3.5
4.0
4.5
5.0
VDD Power Supply Voltage (V)
5.5
C012
At 30°C
Figure 15. IDD vs Temperature at Various VDD
Figure 16. TAO Line Regulation
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VTAO (V)
Typical Performance Characteristics (continued)
Time (µs)
Conditions:
Various VDD and CLOAD
VDD=3.3V
Top trace is T_ON
Bottom trace is TAO
Figure 17. Start-up Response
Figure 18. TAO Response to T_ON
3.00
VTAO Normalized at VDD=2.7V (mV)
Adjacent Device Matching (C)
0.60
Max Limit when
using LUT
0.50
0.40
0.30
0.20
0.10
-55°C
-20°C
10°C
20°C
2.50
2.00
1.50
1.00
0.50
0.00
-0.50
0.00
±60 ±40 ±20
0
20
40
60
80
2.0
100 120 140 160
DUT Temperature (C)
2.5
VDD=2.7V
using LUT table for conversion of voltage to temperature
3.5
4.0
4.5
5.0
5.5
C019
at various temperatures
Figure 19. LMT70A Matching of Adjacent Units on Tape and
Reel
Figure 20. Line Regulation Temperature Variation: VTAO vs
Supply Voltage
2.5
7.E-07
Output Noise Level (V/sqrt(Hz))
2.4
2.3
2.2
VDD (V)
3.0
VDD Power Supply Voltage (V)
C020
2.1
2.0
1.9
1.8
1.7
1.6
6.E-07
5.E-07
4.E-07
3.E-07
2.E-07
1.E-07
0.E+00
1.5
±60 ±40 ±20
0
20
40
60
80
100 120 140 160
DUT Temperature ( C)
1
10
100
1000
10000
Frequency (Hz)
C018
100000
C027
Figure 21. Minimum Recommended Supply Voltage
Temperature Sensitivity
Figure 22. Output Noise vs Frequency
10
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9 Detailed Description
9.1 Overview
The LMT70 is a precision analog output temperature sensor. It includes an output switch that is controlled by the
T_ON digital input. The output switch enables the multiplexing of several devices onto a single ADC input thus
expanding on the ADC input multiplexer capability.
The temperature sensing element is comprised of simply stacked BJT base emitter junctions that are biased by a
current source. The temperature sensing element is then buffered by a precision amplifier before being
connected to the output switch. The output amplifier has a simple class AB push-pull output stage that enables
the device to easily source and sink current.
9.2 Functional Block Diagram
VDD
T_ON
TAO
Thermal Diodes
LMT70
GND
9.3 Feature Description
9.3.1 Temperature Analog Output (TAO)
The TAO push-pull output provides the ability to sink and source current. This is beneficial when, for example,
driving dynamic loads like an input stage on an analog-to-digital converter (ADC). In these applications the
source current is required to quickly charge the input capacitor of the ADC. See the Typical Application section
for more discussion of this topic. The LMT70 is ideal for this and other applications which require strong source
or sink current.
9.3.1.1 LMT70 Output Transfer Function
The LMT70 output voltage transfer function appears to be linear, but upon close inspection it can be seen that it
is truly not linear and can be better described by a second or third order transfer function equation.
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Feature Description (continued)
Figure 23. LMT70 Output Transfer Function
9.3.1.1.1 First Order Transfer Function
A first order transfer function can be used to calculate the temperature LMT70 is sensing but over a wide
temperature range it is the least accurate method. An equation can be easily generated using the LUT (Look-Up
Table) information found in Electrical Characteristics Temperature Lookup Table (LUT) .
Over a narrow 10°C temperature range a linear equation will yield very accurate results. It is actually
recommended that over a 10°C temperature range linear interpolation be used to calculate the temperature the
device is sensing. When this method is used the accuracy minimum and maximum specifications would meet the
values given in Figure 3.
For example the first order equation between 20°C and 30°C can be generated using the typical output voltage
levels as given in Electrical Characteristics Temperature Lookup Table (LUT) and partially repeated here for
reference from 20°C to 50°C:
12
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Feature Description (continued)
Table 1. Output Voltage LUT
Temperature (°C)
VTAO (mV)
Local Slope (mV/°C)
MIN
TYP
MAX
20
994.367
995.050
995.734
-5.171
30
942.547
943.227
943.907
-5.194
40
890.423
891.178
891.934
-5.217
50
838.097
838.882
839.668
-5.241
First calculate the slope:
m =(T1 – T2) ÷ [(VTAO (T1) – VTAO (T2)]
m = (20°C - 30°C) ÷ (995.050 mV – 943.227 mV)
m = –0.193 °C/mV
Then calculate the y intercept b:
b = (T1) – (m × VTAO(T1))
b = 20°C – (–0.193 °C/mV × 995.050 mV)
b = 212.009°C
Thus the final equation used to calculate the measured temperature (TM) in the range between 20°C and 30°C is:
TM = m × VTAO + b
TM = –0.193 °C/mV × VTAO + 212.009°C
where VTAO is in mV and TM is in °C.
9.3.1.1.2 Second Order Transfer Function
A second order transfer function can give good results over a wider limited temperature range. Over the full
temperature range of -55°C to +150°C a single second order transfer function will have increased error at the
temperature extremes. Using least squares sum method a best fit second order transfer function was generated
using the values in Electrical Characteristics Temperature Lookup Table (LUT):
TM = a (VTAO)2+ b (VTAO) + c
where:
Best fit for -55°C to 150°C
Best fit for -10°C to 110°C
a
-8.451576E-06
-7.857923E-06
b
-1.769281E-01
-1.777501E-01
c
2.043937E+02
2.046398E+02
and VTAO is in mV and TM is in °C.
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9.3.1.1.3 Third Order Transfer Function
Over a wide temperature range the most accurate single equation is a third order transfer function. Using least
squares sum method a best fit third order transfer function was generated using the values in Figure 3:
TM = a (VTAO)3 + b (VTAO)2 + c(VTAO) + d
where:
Best fit for -55°C to 150°C
Best fit for -10°C to 110°C
a
-1.064200E-09
-1.809628E-09
b
-5.759725E-06
-3.325395E-06
c
-1.789883E-01
-1.814103E-01
d
2.048570E+02
2.055894E+02
and VTAO is in mV and TM is in °C.
9.3.1.2 LMT70A TAO Matching
In order to meet the matching specification of the LMT70A, two units must be picked from adjacent positions
from one tape and reel. If PCB rework is required, involving the LMT70A, then the pair of the LMT70A matched
units must be replaced. Matching features (which include, without limitation, electrical matching characteristics of
adjacent Components as they are delivered in original packaging from TI) are warranted solely to the extent that
the purchaser can demonstrate to TI’s satisfaction that the particular Component(s) at issue were adjacent in
original packaging as delivered by TI. Customers should be advised that the small size of these components
means they are not individually traceable at the unit level and it may be difficult to establish the original position
of the Components once they have been removed from that original packaging as delivered by TI.
9.3.1.3 TAO Noise Considerations
A load capacitor on TAO pin can help to filter noise.
For noisy environments, TI recommends at minimum 100 nF supply decoupling capacitor placed close across
VDD and GND pins of LMT70.
9.3.1.4 TAO Capacitive Loads
TAO handles capacitive loading well. In an extremely noisy environment, or when driving a switched sampling
input on an ADC, it may be necessary to add some filtering to minimize noise coupling. Without any precautions,
the VTAO can drive a capacitive load less than or equal to 1 nF as shown in Figure 24. For capacitive loads
greater than 1 nF, a series resistor is required on the output, as shown in Figure 25, to maintain stable
conditions.
VDD
OPTIONAL
BYPASS
CAPACITANCE
T_ON
LMT70
TAO
CLOAD
1.1 nF
Figure 24. LMT70 No Isolation Resistor Required
14
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OPTIONAL
BYPASS
CAPACITANCE
VDD
T_ON
LMT70
TAO
RS
CLOAD
1.1 nF
Figure 25. LMT70 With Series Resistor for Capacitive Loading Greater than 1 nF
Table 2. CLOAD and RS Values of Figure 25
CLOAD
Minimum RS
1.1 to 90 nF
3 kΩ
90 to 900 nF
1.5 kΩ
0.9 μF
750 Ω
9.3.2 TON Digital Input
The T_ON digital input enables and disables the analog output voltage presented at the TAO pin by controlling
the state of the internal switch that is in series with the internal temperature sensor circuitry output. When T_ON
is driven to a logic "HIGH" the temperature sensor output voltage is present on the TAO pin. When T_ON is set
to a logic "LOW" the TAO pin is set to a high impedance state.
9.3.3 Light Sensitivity
Although the LMT70 package has a protective backside coating that reduces the amount of light exposure on the
die, unless it is fully shielded, ambient light will still reach the active region of the device from the side of the
package. Depending on the amount of light exposure in a given application, an increase in temperature error
should be expected. In circuit board tests under ambient light conditions, a typical increase in error may not be
observed and is dependent on the angle that the light approaches the package. The LMT70 is most sensitive to
IR radiation. Best practice should include end-product packaging that provides shielding from possible light
sources during operation.
9.4 Device Functional Modes
The LMT70 is a simple precise analog output temperature sensor with a switch in series with its output. It
has only two functional modes: output on or output off.
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10 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
10.1 Application Information
The LMT70 analog output temperature sensor is an ideal device to connect to an integrated 12-Bit ADC such as
that found in the MSP430 microcontroller family.
Applications for the LMT70 included but are not limited to: IoT based temperature sensor nodes, medical fitness
equipment (e.g. thermometers, fitness/smart bands or watches, activity monitors, human body temperature
monitor), Class AA or lower RTD replacement, precision NTC or PTC thermistor replacement, instrumentation
temperature compensation, metering temperature compensation (e. g. heat cost allocator, heat meter).
10.2 Typical Application
2.2V to 3.6V
MSP430
P2.5_VREF
1.5V
Vref
VDD
T_ON
P2.3
LMT70
TAO
M
U
X
ADC
Figure 26. Typical Application Schematic
Most CMOS ADCs found in microcontrollers and ASICs have a sampled data comparator input structure. When
the ADC charges the sampling cap, it requires instantaneous charge from the output of the analog source such
as the LMT70 temperature sensor and many op amps. This requirement is easily accommodated by the addition
of a capacitor (CFILTER) or the extension of the ADC acquisition time thus slowing the ADC sampling rate. The
size of CFILTER depends on the size of the sampling capacitor and the sampling frequency. Since not all ADCs
have identical input stages, the charge requirements will vary. The general ADC application shown in Figure 27
is an example only. The application in Figure 26 was actually tried and the extension of the MSP430 12-Bit ADC
acquisition time was all that was necessary in order to accommodate the LMT70's output stage drive capability.
16
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Typical Application (continued)
SAR Analog-to-Digital Converter
Reset
+2.0V to +5.5V
Input
Pin
LMT70
VDD
RIN
Sample
TAO
T_ON
CFILTER
CBP
CSAMPLE
CPIN
GND
Figure 27. Suggested Connection to a Sampling Analog-to-Digital Converter Input Stage
10.2.1 Design Requirements
The circuit show in Figure 26 will support the design requirements as shown in Table 3.
Table 3. Design Requirements
PARAMETER
TARGET SPECIFICATION
Temperature Range
-40°C to +150°C LMT70, -40°C to +85°C for MSP430
Accuracy
±0.2°C typical over full temperature range
VDD
2.2V to 3.6V with typical of 3.0V
IDD
12µA
10.2.2 Detailed Design Procedure
10.2.2.1 Temperature Algorithm Selection
Of the three algorithms presented in this datasheet, linear interpolation, second order transfer function or third
order transfer function, the one selected will be determined by the users microcontroller resources and the
temperature range that will be sensed. Therefore, a comparison of the expected accuracy from the LMT70 is
given here. The following curves show effect on the accuracy of the LMT70 when using each of the different
algorithms/equations given in LMT70 Output Transfer Function. The first curve (Figure 28) shows the
performance when using linear interpolation of the LUT values shown in Electrical Characteristics Temperature
Lookup Table (LUT) of every 10°C and provides the best performance. Linear interpolation of the LUT values
shown in Electrical Characteristics Temperature Lookup Table (LUT) is used to determine the LMT70 min/max
accuracy limits as shown in the Electrical Characteristics and the red lines of Figure 28. The other lines in the
middle of Figure 28 show independent device performance. The green limit lines, shown in the subsequent
figures, apply for the specific equation used to convert the output voltage of the LMT70 to temperature. The
equations are shown under each figure for reference purposes. The green lines show the min/max limits when
set in a similar manner to the red limit lines of Figure 28. The limits shown in red for Figure 28 are repeated in all
the figures of this section for comparison purposes.
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0.60
0.60
0.50
0.50
0.40
0.40
Max Limit
0.30
0.10
0.00
-0.10
-0.20
-0.30
0.20
0.10
0.00
-0.10
-0.20
-0.30
Min Limit
-0.40
-0.40
-0.50
-0.50
-0.60
20
40
60
80
100 120 140 160
DUT Temperature (C)
Temp
(°C)
VTAO
(mV)
TYP
995.050
943.227
891.178
838.882
MIN
994.367
942.547
890.423
838.097
20
30
40
50
±60 ±40 ±20
Min Limit when
using Equation
MAX
995.734
943.907
891.934
839.668
20
40
60
80
100 120 140 160
DUT Temperature (C)
C016
TM = -1.064200E-09 (VTAO)3 – 5.759725E-06 (VTAO)2 –
1.789883E-01(VTAO) + 2.048570E+02
Local
Slope
(mV/°C)
-5.171
-5.194
-5.217
-5.241
Figure 29. Using Third Order Transfer Function Best Fit 55°C to +150°C
0.60
Max Limit when
using LUT
0.50
Max Limit when
using Equation
Max Limit when
using Equation
Max Limit when
using LUT
0.40
0.30
Accuracy (C)
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
-0.10
-0.20
-0.30
-0.40
-0.50
-0.60
-0.70
0
C001
Figure 28. LMT70 Performance Using LUT and Linear
Interpolation
Accuracy (C)
Min Limit when
using LUT
-0.60
0
±60 ±40 ±20
0.20
0.10
0.00
-0.10
-0.20
-0.30
Min Limit when
using LUT
Min Limit when
using LUT
-0.40
Min Limit when
using Equation
-0.50
Min Limit when
using Equation
-0.60
±60 ±40 ±20
0
20
40
60
80
100 120 140 160
DUT Temperature (C)
±60 ±40 ±20
Figure 30. Using Third Order Transfer Function Best Fit 10°C to +110°C
0
20
40
60
80
100 120 140 160
DUT Temperature (C)
C017
TM = -1.809628E-09 (VTAO)3 – 3.325395E-06 (VTAO)2 –
1.814103E-01(VTAO) + 2.055894E+02
18
Max Limit when
using Equation
Max Limit when
using LUT
0.30
0.20
Accuracy (C)
Accuracy (C)
www.ti.com
C014
TM = -8.451576E-06 (VTAO)2– 1.769281E-01 (VTAO) +
2.043937E+02
Figure 31. Using Second Order Transfer Function Best Fit
-55°C to 150°C
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0.60
0.50
0.40
Max Limit when
using Equation
Max Limit when
using LUT
Accuracy (C)
0.30
0.20
0.10
0.00
-0.10
-0.20
-0.30
Min Limit when
using LUT
-0.40
-0.50
Min Limit when
using Equation
-0.60
±60 ±40 ±20
0
20
40
60
80
100 120 140 160
DUT Temperature (C)
C015
TM = -7.857923E-06 (VTAO)2 – 1.777501E-01 (VTAO) + 2.046398E+02
Figure 32. Using Second Order Transfer Function Best Fit -10°C to 110°C
10.2.2.2 ADC Requirements
The ADC resolution and its specifications as well as reference voltage and its specifications will determine the
overall system accuracy that you can obtain. For this example the 12-bit SAR ADC found in the MSP430 was
used as well as it's integrated reference. At first glance the specifications may not seem to be precise enough to
actually be used with the LMT70 but the MSP430 ADC and integrated reference errors are actually measured
during production testing of the MSP430. Values are then provided to user for software calibration. These
calibration values are located in the MSP430A device descriptor tag-length-value (TLV) structure and found in
the device-specific datasheet. The MSP430 Users Guide includes information on how to use these calibration
values to calibrate the ADC reading. The specific values used to calibrate the ADC readings are:
CAL_ADC_15VREF_FACTOR, CAL_ADC_GAIN_FACTOR and CAL_ADC_OFFSET.
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10.2.3 Finer Resolution LUT
The following table is given for reference only and not meant to be used for calculation purposes.
Temp
(°C)
VTAO
(mV)
Temp
(°C)
TYP
VTAO
(mV)
Temp
(°C)
TYP
VTAO
(mV)
Temp
(°C)
TYP
VTAO
(mV)
Temp
(°C)
TYP
VTAO
(mV)
Temp
(°C)
TYP
VTAO
(mV)
Temp
(°C)
TYP
VTAO
(mV)
TYP
-30
1250.398
0
1097.987
30
943.227
60
786.360
90
627.490
120
466.760
-29
1244.953
1
1092.532
31
937.729
61
780.807
91
621.896
121
460.936
-28
1239.970
2
1087.453
32
932.576
62
775.580
92
616.603
122
455.612
-27
1234.981
3
1082.370
33
927.418
63
770.348
93
611.306
123
450.280
-26
1229.986
4
1077.282
34
922.255
64
765.113
94
606.006
124
444.941
-55
1375.219
-25
1224.984
5
1072.189
35
917.087
65
759.873
95
600.701
125
439.593
-54
1370.215
-24
1219.977
6
1067.090
36
911.915
66
754.628
96
595.392
126
434.238
-53
1365.283
-23
1214.963
7
1061.987
37
906.738
67
749.380
97
590.079
127
428.875
-52
1360.342
-22
1209.943
8
1056.879
38
901.556
68
744.127
98
584.762
128
423.504
-51
1355.395
-21
1204.916
9
1051.765
39
896.370
69
738.870
99
579.442
129
418.125
-50
1350.441
-20
1199.884
10
1046.647
40
891.178
70
733.608
100
574.117
130
412.739
-49
1345.159
-19
1194.425
11
1041.166
41
885.645
71
728.055
101
568.504
131
406.483
-48
1340.229
-18
1189.410
12
1036.062
42
880.468
72
722.804
102
563.192
132
401.169
-47
1335.293
-17
1184.388
13
1030.952
43
875.287
73
717.550
103
557.877
133
395.841
-46
1330.352
-16
1179.361
14
1025.838
44
870.100
74
712.292
104
552.557
134
390.499
-45
1325.405
-15
1174.327
15
1020.720
45
864.909
75
707.029
105
547.233
135
385.144
-44
1320.453
-14
1169.288
16
1015.596
46
859.713
76
701.762
106
541.905
136
379.775
-43
1315.496
-13
1164.242
17
1010.467
47
854.513
77
696.491
107
536.573
137
374.393
-42
1310.534
-12
1159.191
18
1005.333
48
849.307
78
691.217
108
531.236
138
368.997
-41
1305.566
-11
1154.134
19
1000.194
49
844.097
79
685.937
109
525.895
139
363.587
-40
1300.593
-10
1149.070
20
995.050
50
838.882
80
680.654
110
520.551
140
358.164
-39
1295.147
-9
1143.654
21
989.583
51
833.343
81
675.073
111
514.886
141
351.937
-38
1290.202
-8
1138.599
22
984.450
52
828.141
82
669.803
112
509.557
142
346.508
-37
1285.250
-7
1133.540
23
979.313
53
822.934
83
664.528
113
504.223
143
341.071
-36
1280.291
-6
1128.476
24
974.171
54
817.723
84
659.250
114
498.885
144
335.625
-35
1275.326
-5
1123.407
25
969.025
55
812.507
85
653.967
115
493.542
145
330.172
-34
1270.353
-4
1118.333
26
963.875
56
807.287
86
648.680
116
488.195
146
324.711
-33
1265.375
-3
1113.254
27
958.720
57
802.062
87
643.389
117
482.843
147
319.241
-32
1260.389
-2
1108.170
28
953.560
58
796.832
88
638.094
118
477.486
148
313.764
-31
1255.397
-1
1103.081
29
948.396
59
791.598
89
632.794
119
472.125
149
308.279
20
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Temp
(°C)
VTAO
(mV)
TYP
150
302.785
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10.2.4 Application Curves
The LMT70 performance using the MSP430 with integrated 12-bit ADC is shown in Figure 33. This curve
includes the error of the MSP430 integrated 12-bit ADC and reference as shown in the schematic Figure 26. The
MSP430 was kept at room temperature and the LMT70 was submerged in a precision temperature calibration oil
bath. A calibrated temperature probe was used to monitor the temperature of the oil. As can be seen in Figure 33
the combined performance on the MSP430 and the LMT70 is better than 0.12°C for the entire -40°C to +150°C
temperature range. The only calibration performed was with software using the MSP430A device descriptor taglength-value (TLV) calibration values for ADC and VREF error.
Temperature Reading Error (C)
0.50
0.40
0.30
0.20
0.10
0.00
±0.10
±0.20
±0.30
±0.40
±0.50
±60 ±40 ±20
0
20
40
60
80
100 120 140 160
LMT70 Temperature (C)
C023
Figure 33. LMT70 with MSP430 typical performance
10.3 System Examples
Coin Cell
Battery
Coin Cell
Battery
2.8V to 3.6V
2.2V to 3.2V
2.2V to 3.6V
GPIO1
CC430F6147
MSP430
P2.0
GPIO2
P2.5_VREF
GPIO2
P2.1
P2.3
P2.5_VREF
1.5V
Vref
VDD
T_ON
TAO
VDD
M
U
X
100k
P2.3
LMT70
P2.3
LMT70
16-bit
Counter
VDD
T_ON
+
CCR
T_1
ADC
-
47nF
Comparator B
VDD
T_ON
T_ON
LMT70
0.25 Vref
LMT70
T_2
TAO
Figure 34. Multiple LMT70s connected to one 12-bit ADC
channel on an MSP430
Figure 35. Multiple LMT70s connected to a slope ADC for
high resolution
11 Power Supply Recommendations
Power supply bypass capacitors are optional and may be required if the supply line is noisy. It is recommended
that a local supply decoupling capacitor be used to reduce noise. For noisy environments, TI recommends a 100
nF supply decoupling capacitor placed closed across VDD and GND pins of LMT70.
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21
LMT70, LMT70A
SNIS187A – MARCH 2015 – REVISED JULY 2015
www.ti.com
12 Layout
12.1 Layout Guidelines
The LMT70 can be applied easily in the same way as other integrated-circuit temperature sensors. It can be
glued or cemented to a surface. The temperatures of the lands and traces to the other leads of the LMT70 will
also affect the temperature reading.
12.1.1 Mounting and Temperature Conductivity
Alternatively, the LMT70 can be mounted inside a sealed-end metal tube, and can then be dipped into a bath or
screwed into a threaded hole in a tank. As with any IC, the LMT70 and accompanying wiring and circuits must be
kept insulated and dry, to avoid leakage and corrosion. This is especially true if the circuit may operate at cold
temperatures where condensation can occur. If moisture creates a short circuit from the TAO output to ground or
VDD, the TAO output from the LMT70 will not be correct. Printed-circuit coatings are often used to ensure that
moisture cannot corrode the leads or circuit traces.
The LMT70's junction temperature is the actual temperature being measured. The thermal resistance junction-toambient (RθJA) is the parameter (from Thermal Information) used to calculate the rise of a device junction
temperature due to its power dissipation. Equation 1 is used to calculate the rise in the LMT70's die temperature.
7J 7A 5TJA ¬ª 9DD,Q 9DD ±9TEMP ,L ¼º
where
•
•
•
TA is the ambient temperature.
IQ is the quiescent current.
IL is the load current on VTEMP.
(1)
For example, in an application where TA = 30°C, VDD = 3 V, IDD = 12µA, VTAO = 943.227 mV, and IL = 0 μA, the
total temperature rise would be [187°C/W × 3 V × 12 μA] = 0.007°C. To minimize self-heating, the load current
on TAO pin should be minimized.
12.2 Layout Example
VIA to power plane
VIA to ground plane
0.01µ F
22
GND
VDD
TAO
T_ON
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SNIS187A – MARCH 2015 – REVISED JULY 2015
13 Device and Documentation Support
13.1 Related Links
The table below lists quick access links. Categories include technical documents, support and community
resources, tools and software, and quick access to sample or buy.
Table 4. Related Links
PARTS
PRODUCT FOLDER
SAMPLE & BUY
TECHNICAL
DOCUMENTS
TOOLS &
SOFTWARE
SUPPORT &
COMMUNITY
LMT70
Click here
Click here
Click here
Click here
Click here
LMT70A
Click here
Click here
Click here
Click here
Click here
13.2 Documentation Support
13.2.1 Related Documentation
Reflow Temperature Profile specifications. Refer to www.ti.com/packaging.
IC Package Thermal Metrics application report, SPRA953
13.3 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
13.4 Trademarks
E2E is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
13.5 Electrostatic Discharge Caution
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
13.6 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
14 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
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Product Folder Links: LMT70 LMT70A
23
PACKAGE OPTION ADDENDUM
www.ti.com
12-May-2015
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
MSL Peak Temp
(2)
(6)
(3)
Op Temp (°C)
Device Marking
(4/5)
LMT70AYFQR
ACTIVE
DSBGA
YFQ
4
3000
Green (RoHS
& no Sb/Br)
SNAGCU
Level-1-260C-UNLIM
-55 to 150
LMT70AYFQT
ACTIVE
DSBGA
YFQ
4
250
Green (RoHS
& no Sb/Br)
SNAGCU
Level-1-260C-UNLIM
-55 to 150
LMT70YFQR
ACTIVE
DSBGA
YFQ
4
3000
Green (RoHS
& no Sb/Br)
SNAGCU
Level-1-260C-UNLIM
-55 to 150
LMT70YFQT
ACTIVE
DSBGA
YFQ
4
250
Green (RoHS
& no Sb/Br)
SNAGCU
Level-1-260C-UNLIM
-55 to 150
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3)
MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5)
Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6)
Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
12-May-2015
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
12-May-2015
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
LMT70AYFQR
DSBGA
YFQ
4
3000
178.0
8.4
LMT70AYFQT
DSBGA
YFQ
4
250
178.0
LMT70YFQR
DSBGA
YFQ
4
3000
178.0
LMT70YFQT
DSBGA
YFQ
4
250
178.0
0.94
0.94
0.71
4.0
8.0
Q1
8.4
0.94
0.94
0.71
4.0
8.0
Q1
8.4
0.94
0.94
0.71
4.0
8.0
Q1
8.4
0.94
0.94
0.71
4.0
8.0
Q1
Pack Materials-Page 1
W
Pin1
(mm) Quadrant
PACKAGE MATERIALS INFORMATION
www.ti.com
12-May-2015
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
LMT70AYFQR
DSBGA
YFQ
4
3000
210.0
185.0
35.0
LMT70AYFQT
DSBGA
YFQ
4
250
210.0
185.0
35.0
LMT70YFQR
DSBGA
YFQ
4
3000
210.0
185.0
35.0
LMT70YFQT
DSBGA
YFQ
4
250
210.0
185.0
35.0
Pack Materials-Page 2
MECHANICAL DATA
YFQ0004xxx
D
0.600±0.075
E
TMD04XXX (Rev A)
D: Max = 0.914 mm, Min =0.854 mm
E: Max = 0.914 mm, Min =0.854 mm
4215073/A
NOTES:
A. All linear dimensions are in millimeters. Dimensioning and tolerancing per ASME Y14.5M-1994.
B. This drawing is subject to change without notice.
www.ti.com
12/12
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