LMT87-Q1
SNIS202A – OCTOBER 2017 – REVISED JUNE 2022
LMT87-Q1 2.7-V, SC70,
Analog Temperature Sensors With Class-AB Output
1 Features
3 Description
•
The LMT87-Q1 device is a precision CMOS
temperature sensor with ±0.4°C typical accuracy
(±2.7°C maximum) and a linear analog output voltage
that is inversely proportional to temperature. The 2.7V supply voltage operation, 5.4-μA quiescent current,
and 0.7-ms power-on time enable effective powercycling architectures to minimize power consumption
for battery-powered applications such as drones
and sensor nodes. The LMT87-Q1-Q1 device
is AEC-Q100 Grade 0 qualified and maintains
±2.7°C maximum accuracy over the full operating
temperature range without calibration; this makes the
LMT87-Q1-Q1 suitable for automotive applications
such as infotainment, cluster, and powertrain systems.
The accuracy over the wide operating range and other
features make the LMT87-Q1 an excellent alternative
to thermistors.
•
•
•
•
•
•
•
•
•
•
LMT87-Q1-Q1 is AEC-Q100 Qualified for
Automotive Applications:
– Device Temperature Grade 0: –40°C to +150°C
– Device HBM ESD Classification Level 2
– Device CDM ESD Classification Level C6
Functional Safety-Capable
– Documentation available to aid functional safety
system design
Very Accurate: ±0.4°C Typical
Low 2.7-V Operation
Average Sensor Gain of –13.6 mV/°C
Low 5.4-µA Quiescent Current
Wide Temperature Range: –50°C to 150°C
Output is Short-Circuit Protected
Push-Pull Output With ±50-µA Drive Capability
Footprint Compatible With the Industry-Standard
LM20/19 and LM35 Temperature Sensors
Cost-Effective Alternative to Thermistors
For devices with different average sensor gains and
comparable accuracy, refer to Comparable Alternative
Devices for alternative devices in the LMT8x family.
2 Applications
Automotive
Infotainment and Cluster
Powertrain Systems
Smoke and Heat Detectors
Drones
Appliances
Device Information(1)
PART NUMBER
LMT87-Q1
(1)
100%
PACKAGE
SOT (5)
BODY SIZE (NOM)
2.00 mm × 1.25 mm
For all available packages, see the orderable addendum at
the end of the data sheet.
VDD (+2.7V to +5.5V)
90%
FINAL TEMPERATURE
•
•
•
•
•
•
80%
VDD
70%
60%
LMT87
50%
CBP
40%
OUT
30%
20%
LMT8xLPG
Thermistor
10%
GND
0
0
20
40
60
TIME (s)
80
100
D003
* Fast thermal response NTC
Thermal Time Constant
Copyright © 2016, Texas Instruments Incorporated
Output Voltage vs Temperature
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.
LMT87-Q1
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SNIS202A – OCTOBER 2017 – REVISED JUNE 2022
Table of Contents
1 Features............................................................................1
2 Applications..................................................................... 1
3 Description.......................................................................1
4 Revision History.............................................................. 2
5 Device Comparison......................................................... 3
6 Pin Configuration and Functions...................................3
7 Specifications.................................................................. 4
7.1 Absolute Maximum Ratings........................................ 4
7.2 ESD Ratings............................................................... 4
7.3 Recommended Operating Conditions.........................4
7.4 Thermal Information....................................................4
7.5 Accuracy Characteristics............................................ 5
7.6 Electrical Characteristics.............................................5
7.7 Typical Characteristics................................................ 6
8 Detailed Description........................................................8
8.1 Overview..................................................................... 8
8.2 Functional Block Diagram........................................... 8
8.3 Feature Description.....................................................8
8.4 Device Functional Modes..........................................10
9 Application and Implementation.................................. 12
9.1 Application Information............................................. 12
9.2 Typical Applications.................................................. 12
10 Power Supply Recommendations..............................13
11 Layout........................................................................... 14
11.1 Layout Guidelines................................................... 14
11.2 Layout Example...................................................... 14
12 Device and Documentation Support..........................15
12.1 Receiving Notification of Documentation Updates..15
12.2 Support Resources................................................. 15
12.3 Trademarks............................................................. 15
12.4 Electrostatic Discharge Caution..............................15
12.5 Glossary..................................................................15
13 Mechanical, Packaging, and Orderable
Information.................................................................... 15
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision * (October 2017) to Revision A (June 2022)
Page
• Updated the numbering format for tables, figures, and cross-references throughout the document..................1
• Added Functional Safety bullets to the Features section....................................................................................1
2
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5 Device Comparison
Table 5-1. Available Device Packages
ORDER NUMBER(1)
PACKAGE
PIN
BODY SIZE (NOM)
MOUNTING TYPE
LMT87DCK
SOT (AKA(2): SC70, DCK)
5
2.00 mm × 1.25 mm
Surface Mount
LMT87LP
TO-92 (AKA(2): LP)
3
4.30 mm × 3.50 mm
Through-hole; straight leads
LMT87LPG
TO-92S (AKA(2): LPG)
3
4.00 mm × 3.15 mm
Through-hole; straight leads
LMT87LPM
TO-92
(AKA(2):
3
4.30 mm × 3.50 mm
Through-hole; formed leads
LMT87DCK-Q1
SOT (AKA(2): SC70, DCK)
5
2.00 mm × 1.25 mm
Surface Mount
(1)
(2)
LPM)
For all available packages and complete order numbers, see the Package Option addendum at the end of the data sheet.
AKA = Also Known As
Table 5-2. Comparable Alternative Devices
DEVICE NAME
AVERAGE OUTPUT SENSOR GAIN
POWER SUPPLY RANGE
LMT84-Q1
–5.5 mV/°C
1.5 V to 5.5 V
LMT85-Q1
–8.2 mV/°C
1.8 V to 5.5 V
LMT86-Q1
–10.9 mV/°C
2.2 V to 5.5 V
LMT87-Q1
–13.6 mV/°C
2.7 V to 5.5 V
6 Pin Configuration and Functions
1
5
VDD
VDD
2
GND
LMT87
3
4
OUT
VDD
Figure 6-1. DCK Package 5-Pin SOT (SC70) Top View
Table 6-1. Pin Functions
PIN
NAME
GND
SOT (SC70)
2(1)
TYPE
Ground
DESCRIPTION
EQUIVALENT CIRCUIT
N/A
FUNCTION
Power Supply Ground
VDD
OUT
3
Analog
Output
VDD
1, 4, 5
Power
Outputs a voltage that is inversely proportional
to temperature
GND
(1)
N/A
Positive Supply Voltage
Direct connection to the back side of the die
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7 Specifications
7.1 Absolute Maximum Ratings
See (1) (3)
MIN
MAX
UNIT
Supply voltage
–0.3
6
V
Voltage at output pin
–0.3
(VDD + 0.5)
V
Output current
–7
7
mA
Input current at any pin(2)
–5
Maximum junction temperature (TJMAX)
Storage temperature Tstg
(1)
(2)
(3)
–65
5
mA
150
°C
150
°C
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.
When the input voltage (VI) at any pin exceeds power supplies (VI < GND or VI > V), the current at that pin should be limited to 5 mA.
Soldering process must comply with Reflow Temperature Profile specifications. Refer to www.ti.com/packaging.
7.2 ESD Ratings
VALUE
UNIT
LMT87DCK-Q1 in SC70 package
V(ESD)
(1)
Electrostatic discharge
Human-body model (HBM), per AEC Q100-002(1)
±2500
Charged-device model (CDM), per AEC Q100-011
±1000
V
AEC Q100-002 indicates that HBM stressing shall be in accordance with the ANSI/ESDA/JEDEC JS-001 specification.
7.3 Recommended Operating Conditions
MIN
MAX
TMIN ≤ TA ≤ TMAX
Specified temperature
°C
−50 ≤ TA ≤ 150
Supply voltage (VDD)
2.7
UNIT
°C
5.5
V
7.4 Thermal Information
LMT87-Q1
THERMAL
METRIC(1) (2)
DCK (SOT/SC70)
UNIT
5 PINS
RθJA
Junction-to-ambient thermal resistance (3) (4)
275
°C/W
RθJC(top)
Junction-to-case (top) thermal resistance
84
°C/W
RθJB
Junction-to-board thermal resistance
56
°C/W
ψJT
Junction-to-top characterization parameter
1.2
°C/W
ψJB
Junction-to-board characterization parameter
55
°C/W
(1)
(2)
(3)
(4)
4
For information on self-heating and thermal response time see section Mounting and Thermal Conductivity.
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report.
The junction to ambient thermal resistance (RθJA) under natural convection is obtained in a simulation on a JEDEC-standard, High-K
board as specified in JESD51-7, in an environment described in JESD51-2. Exposed pad packages assume that thermal vias are
included in the PCB, per JESD 51-5.
Changes in output due to self-heating can be computed by multiplying the internal dissipation by the thermal resistance.
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7.5 Accuracy Characteristics
These limits do not include DC load regulation. These stated accuracy limits are with reference to the values in Table 8-1.
PARAMETER
CONDITIONS
70°C to 150°C; VDD = 3.0 V to 5.5 V
MIN(1)
TYP
MAX(1)
–2.7
±0.4
2.7
20°C to 40°C; VDD = 2.7 V to 5.5 V
±0.6
20°C to 40°C; VDD = 3.4 V to 5.5 V
–2.7
2.7
±0.3
–50°C; VDD = 3.6 V to 5.5 V
–2.7
°C
°C
±0.6
–50°C; VDD = 4.2 V to 5.5 V
(1)
(2)
°C
±0.6
0°C; VDD = 3.6 V to 5.5 V
°C
°C
±0.3
Temperature accuracy(2) 0°C; VDD = 3.0 V to 5.5 V
UNIT
2.7
±0.3
°C
°C
Limits are specific to TI's AOQL (Average Outgoing Quality Level).
Accuracy is defined as the error between the measured and reference output voltages, tabulated in the Transfer Table at the specified
conditions of supply gain setting, voltage, and temperature (expressed in °C). Accuracy limits include line regulation within the
specified conditions. Accuracy limits do not include load regulation; they assume no DC load.
7.6 Electrical Characteristics
Unless otherwise noted, these specifications apply for +VDD = 2.7 V to 5.5 V. MIN and MAX limits apply for TA = TJ = TMIN to
TMAX ; typical limits apply for TA = TJ = 25°C.
PARAMETER
TEST CONDITIONS
MIN(2)
Sensor gain (output transfer
function slope)
Load regulation(3)
Line
Supply current
CL
Output load capacitance
Power-on
time(5)
Output drive
(1)
(2)
(3)
(4)
(5)
MAX (2)
–13.6
Source ≤ 50 μA, (VDD – VOUT) ≥ 200 mV
–1
Sink ≤ 50 μA, VOUT ≥ 200 mV
mV
1
200
TA = 30°C to 150°C, (VDD – VOUT) ≥ 100 mV
TA = –50°C to 150°C, (VDD – VOUT) ≥ 100 mV
TA = TJ = 25°C
μV/V
8.1
μA
5.4
9
μA
0.7
–50
mV
5.4
1100
CL= 0 pF to 1100 pF
UNIT
mV/°C
–0.22
0.26
regulation(4)
IS
TYP (1)
pF
1.9
ms
50
μA
Typicals are at TJ = TA = 25°C and represent most likely parametric norm.
Limits are specific to TI's AOQL (Average Outgoing Quality Level).
Source currents are flowing out of the LMT87-Q1. Sink currents are flowing into the LMT87-Q1.
Line regulation (DC) is calculated by subtracting the output voltage at the highest supply voltage from the output voltage at the lowest
supply voltage. The typical DC line regulation specification does not include the output voltage shift discussed in Output Voltage Shift.
Specified by design and characterization.
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7.7 Typical Characteristics
4
TEMPERATURE ERROR (ºC)
3
2
1
0
-1
-2
-3
-4
-50
-25
0
25
50
75
100 125 150
TEMPERATURE (ºC)
Figure 7-1. Temperature Error vs Temperature
6
Figure 7-2. Minimum Operating Temperature vs Supply Voltage
Figure 7-3. Supply Current vs Temperature
Figure 7-4. Supply Current vs Supply Voltage
Figure 7-5. Load Regulation, Sourcing Current
Figure 7-6. Load Regulation, Sinking Current
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7.7 Typical Characteristics (continued)
Figure 7-7. Change in VOUT vs Overhead Voltage
Figure 7-8. Supply-Noise Gain vs Frequency
Figure 7-9. Output Voltage vs Supply Voltage
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8 Detailed Description
8.1 Overview
The LMT87-Q1 is an analog output temperature sensor. The temperature-sensing element is comprised of a
simple base emitter junction that is forward biased by a current source. The temperature-sensing element is then
buffered by an amplifier and provided to the OUT pin. The amplifier has a simple push-pull output stage thus
providing a low impedance output source.
8.2 Functional Block Diagram
Full-Range Celsius Temperature Sensor (−50°C to +150°C)
VDD
OUT
Thermal Diodes
GND
8.3 Feature Description
8.3.1 LMT87-Q1 Transfer Function
Table 8-1 shows the output voltage of the LMT87-Q1 across the complete operating temperature range. This
table is the reference from which the LMT87-Q1 accuracy specifications (listed in the Accuracy Characteristics
table) are determined. This table can be used, for example, in a host processor look-up table. A file containing
this data is available for download at the LMT87-Q1 product folder under Tools and Software Models.
Table 8-1. LMT87-Q1 Transfer Table
TEMP
(°C)
8
VOUT
(mV)
TEMP
(°C)
VOUT
(mV)
TEMP
(°C)
VOUT
(mV)
TEMP
(°C)
VOUT
(mV)
TEMP
(°C)
VOUT
(mV)
–50
3277
–10
2767
30
2231
70
1679
110
1115
–49
3266
–9
2754
31
2217
71
1665
111
1101
–48
3254
–8
2740
32
2204
72
1651
112
1087
–47
3243
–7
2727
33
2190
73
1637
113
1073
–46
3232
–6
2714
34
2176
74
1623
114
1058
–45
3221
–5
2700
35
2163
75
1609
115
1044
–44
3210
–4
2687
36
2149
76
1595
116
1030
–43
3199
–3
2674
37
2136
77
1581
117
1015
–42
3186
–2
2660
38
2122
78
1567
118
1001
–41
3173
–1
2647
39
2108
79
1553
119
987
–40
3160
0
2633
40
2095
80
1539
120
973
–39
3147
1
2620
41
2081
81
1525
121
958
–38
3134
2
2607
42
2067
82
1511
122
944
–37
3121
3
2593
43
2054
83
1497
123
929
–36
3108
4
2580
44
2040
84
1483
124
915
–35
3095
5
2567
45
2026
85
1469
125
901
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Table 8-1. LMT87-Q1 Transfer Table (continued)
TEMP
(°C)
VOUT
(mV)
TEMP
(°C)
VOUT
(mV)
TEMP
(°C)
VOUT
(mV)
TEMP
(°C)
VOUT
(mV)
TEMP
(°C)
VOUT
(mV)
–34
3082
6
2553
46
2012
86
1455
126
886
–33
3069
7
2540
47
1999
87
1441
127
872
–32
3056
8
2527
48
1985
88
1427
128
858
–31
3043
9
2513
49
1971
89
1413
129
843
–30
3030
10
2500
50
1958
90
1399
130
829
–29
3017
11
2486
51
1944
91
1385
131
814
–28
3004
12
2473
52
1930
92
1371
132
800
–27
2991
13
2459
53
1916
93
1356
133
786
–26
2978
14
2446
54
1902
94
1342
134
771
–25
2965
15
2433
55
1888
95
1328
135
757
–24
2952
16
2419
56
1875
96
1314
136
742
–23
2938
17
2406
57
1861
97
1300
137
728
–22
2925
18
2392
58
1847
98
1286
138
713
–21
2912
19
2379
59
1833
99
1272
139
699
–20
2899
20
2365
60
1819
100
1257
140
684
–19
2886
21
2352
61
1805
101
1243
141
670
–18
2873
22
2338
62
1791
102
1229
142
655
–17
2859
23
2325
63
1777
103
1215
143
640
–16
2846
24
2311
64
1763
104
1201
144
626
–15
2833
25
2298
65
1749
105
1186
145
611
–14
2820
26
2285
66
1735
106
1172
146
597
–13
2807
27
2271
67
1721
107
1158
147
582
–12
2793
28
2258
68
1707
108
1144
148
568
–11
2780
29
2244
69
1693
109
1130
149
553
150
538
Although the LMT87-Q1 is very linear, the response does have a slight umbrella parabolic shape. Table 8-1 very
accurately reflects this shape. The transfer table can be calculated by using the parabolic equation (Equation 1).
mV
mV
ª
º ª
VTEMP mV = 2230.8mV - «13.582
T - 30°C » - «0.00433 2 T - 30°C
°C
¬
¼ ¬
°C
2º
»
¼
(1)
The parabolic equation is an approximation of the transfer table and the accuracy of the equation degrades
slightly at the temperature range extremes. Equation 1 can be solved for T resulting in:
T
13 .582
13 .582
2
4 u 0.00433 u 2230 .8 VTEMP mV
2 u ( 0.00433 )
30
(2)
For an even less accurate linear transfer function approximation, a line can easily be calculated over the desired
temperature range from Table 8-1 using the two-point equation (Equation 3):
·
¹
V - V1 =
V2 - V1
T2 - T1
· u (T - T1)
¹
(3)
where
•
•
•
•
V is in mV,
T is in °C,
T1 and V1 are the coordinates of the lowest temperature,
and T2 and V2 are the coordinates of the highest temperature.
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For example, if the user wanted to resolve this equation, over a temperature range of 20°C to 50°C, they would
proceed as follows:
1958 mV - 2365 mV·
u (T - 20oC)
50oC - 20oC
¹
·
¹
V - 2365 mV =
(4)
o
o
V - 2365 mV = (-13.6 mV / C) u (T - 20 C)
(5)
o
V = (-13.6 mV / C) u T + 2637 mV
(6)
Using this method of linear approximation, the transfer function can be approximated for one or more
temperature ranges of interest.
8.4 Device Functional Modes
8.4.1 Mounting and Thermal Conductivity
The LMT87-Q1 can be applied easily in the same way as other integrated-circuit temperature sensors. It can be
glued or cemented to a surface.
To ensure good thermal conductivity, the backside of the LMT87-Q1 die is directly attached to the GND pin. The
temperatures of the lands and traces to the other leads of the LMT87-Q1 will also affect the temperature reading.
Alternatively, the LMT87-Q1 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 LMT87-Q1 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 output to ground
or VDD, the output from the LMT87-Q1 will not be correct. Printed-circuit coatings are often used to ensure that
moisture cannot corrode the leads or circuit traces.
The thermal resistance junction to ambient (RθJA or θJA) is the parameter used to calculate the rise of a device
junction temperature due to its power dissipation. Use Equation 7 to calculate the rise in the LMT87-Q1 die
temperature:
TJ = TA + TJA ¬ª(VDDIS ) + (VDD - VOUT ) IL ¼º
(7)
where
•
•
•
•
TA is the ambient temperature,
IS is the supply current,
ILis the load current on the output,
and VO is the output voltage.
For example, in an application where TA = 30°C, VDD = 5 V, IS = 5.4 μA, VOUT = 2231 mV, and IL = 2 μA, the
junction temperature would be 30.014°C, showing a self-heating error of only 0.014°C. Because the junction
temperature of the LMT87-Q1 is the actual temperature being measured, take care to minimize the load current
that the LMT87-Q1 is required to drive. The Thermal Information table shows the thermal resistance of the
LMT87-Q1.
8.4.2 Output Noise Considerations
A push-pull output gives the LMT87-Q1 the ability to sink and source significant 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. The LMT87-Q1 is
ideal for this and other applications which require strong source or sink current.
The LMT87-Q1 supply-noise gain (the ratio of the AC signal on VOUT to the AC signal on VDD) was measured
during bench tests. Figure 7-8 shows the typical attenuation found in the Typical Characteristics section. A load
capacitor on the output can help to filter noise.
10
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For operation in very noisy environments, some bypass capacitance should be present on the supply within
approximately 5 centimeters of the LMT87-Q1.
8.4.3 Capacitive Loads
The LMT87-Q1 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, Figure 8-1 shows how the LMT87-Q1 can drive a capacitive load less than or equal to 1100 pF. For
capacitive loads greater than 1100 pF, Figure 8-2 shows how a series resistor may be required on the output.
VDD
LMT87
OPTIONAL
BYPASS
CAPACITANCE
OUT
GND
CLOAD ” 1100 pF
Figure 8-1. LMT87 No Decoupling Required for Capacitive Loads Less Than 1100 pF
VDD
RS
LMT87
OPTIONAL
BYPASS
CAPACITANCE
OUT
GND
CLOAD > 1100 pF
Figure 8-2. LMT87 with Series Resistor for Capacitive Loading Greater Than 1100 pF
Table 8-2. Recommended Series Resistor Values
CLOAD
MINIMUM RS
1.1 nF to 99 nF
3 kΩ
100 nF to 999 nF
1.5 kΩ
1 μF
800 Ω
8.4.4 Output Voltage Shift
The LMT87-Q1 is very linear over temperature and supply voltage range. Due to the intrinsic behavior of an
NMOS/PMOS rail-to-rail buffer, a slight shift in the output can occur when the supply voltage is ramped over the
operating range of the device. The location of the shift is determined by the relative levels of VDD and VOUT. The
shift typically occurs when VDD- VOUT = 1 V.
This slight shift (a few millivolts) takes place over a wide change (approximately 200 mV) in VDD or VOUT.
Because the shift takes place over a wide temperature change of 5°C to 20°C, VOUT is always monotonic. The
accuracy specifications in the Accuracy Characteristics table already include this possible shift.
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9 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, as well as validating and testing their design
implementation to confirm system functionality.
9.1 Application Information
The LMT87-Q1 features make it suitable for many general temperature-sensing applications. It can operate
down to 2.7-V supply with 5.4-µA power consumption.
9.2 Typical Applications
9.2.1 Connection to ADC
Simplified Input Circuit of
SAR Analog-to-Digital Converter
+2.7V to +5.5V
Reset
Input
Pin
LMT87
VDD
CBP
RMUX
RSS
Sample
OUT
GND
CMUX
CFILTER
CSAMPLE
Figure 9-1. Suggested Connection to a Sampling Analog-to-Digital Converter Input Stage
9.2.1.1 Design Requirements
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 LMT87-Q1 temperature sensor and many op amps. This requirement is easily accommodated by the
addition of a capacitor (CFILTER).
9.2.1.2 Detailed Design Procedure
The size of CFILTER depends on the size of the sampling capacitor and the sampling frequency. Because not all
ADCs have identical input stages, the charge requirements will vary. This general ADC application is shown as
an example only.
9.2.1.3 Application Curve
3.5
OUTPUT VOLTAGE (V)
3.0
2.5
2.0
1.5
1.0
0.5
0.0
±50
0
50
100
150
TEMPERATURE (ƒC)
C001
Figure 9-2. Analog Output Transfer Function
12
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9.2.2 Conserving Power Dissipation With Shutdown
VDD
SHUTDOWN
VOUT
LMT87
Any logic
device output
Figure 9-3. Simple Shutdown Connection of the LMT87-Q1
9.2.2.1 Design Requirements
Because the power consumption of the LMT87-Q1 is less than 9 µA, it can simply be powered directly from any
logic gate output and therefore not require a specific shutdown pin. The device can even be powered directly
from a microcontroller GPIO. In this way, it can easily be turned off for cases such as battery-powered systems
where power savings are critical.
9.2.2.2 Detailed Design Procedure
Simply connect the VDD pin of the LMT87-Q1 directly to the logic shutdown signal from a microcontroller.
9.2.2.3 Application Curves
Time: 500 μs/div; Top trace: VDD 1 V/div; Bottom trace: OUT 1
V/div
Figure 9-4. Output Turnon Response Time Without
a Capacitive Load and VDD = 3.3 V
Time: 500 μs/div; Top trace: VDD 2 V/div; Bottom trace: OUT 1
V/div
Figure 9-6. Output Turnon Response Time Without
a Capacitive Load and VDD = 5 V
Time: 500 μs/div; Top trace: VDD 1 V/div; Bottom trace: OUT 1
V/div
Figure 9-5. Output Turnon Response Time With a
1.1-nF Capacitive Load and VDD = 3.3 V
Time: 500 μs/div; Top trace: VDD 2 V/div; Bottom trace: OUT 1
V/div
Figure 9-7. Output Turnon Response Time With a
1.1-nF Capacitive Load and VDD = 5 V
10 Power Supply Recommendations
The low supply current and supply range (2.7 V to 5.5 V) of the LMT87-Q1 allow the device to easily be powered
from many sources. Power supply bypassing is optional and is mainly dependent on the noise on the power
supply used. In noisy systems it may be necessary to add bypass capacitors to lower the noise that is coupled to
the output of the LMT87-Q1.
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11 Layout
11.1 Layout Guidelines
The LMT87-Q1 is extremely simple to layout. If a power-supply bypass capacitor is used, the Layout Example
shows how to connect the capacitor to the device.
11.2 Layout Example
VIA to ground plane
VIA to power plane
VDD
VDD
VDD
GND
OUT
0.01 µ F
VDD
Figure 11-1. SC70 Package Recommended Layout
14
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12 Device and Documentation Support
12.1 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. Click on
Subscribe to updates to register and receive a weekly digest of any product information that has changed. For
change details, review the revision history included in any revised document.
12.2 Support Resources
TI E2E™ support forums are an engineer's go-to source for fast, verified answers and design help — straight
from the experts. Search existing answers or ask your own question to get the quick design help you need.
Linked content is 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.
12.3 Trademarks
TI E2E™ is a trademark of Texas Instruments.
All trademarks are the property of their respective owners.
12.4 Electrostatic Discharge Caution
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled
with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may
be more susceptible to damage because very small parametric changes could cause the device not to meet its published
specifications.
12.5 Glossary
TI Glossary
This glossary lists and explains terms, acronyms, and definitions.
13 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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PACKAGE OPTION ADDENDUM
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PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
LMT87QDCKRQ1
ACTIVE
SC70
DCK
5
3000
RoHS & Green
SN
Level-1-260C-UNLIM
-50 to 150
BVA
LMT87QDCKTQ1
ACTIVE
SC70
DCK
5
250
RoHS & Green
SN
Level-1-260C-UNLIM
-50 to 150
BVA
(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)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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