Analog Devices TMP35, TMP37, TMP36 Datasheet

a
Low Voltage Temperature Sensors
TMP35/TMP36/TMP37
FEATURES Low Voltage Operation (+2.7 V to +5.5 V) Calibrated Directly in 8C 10 mV/8C Scale Factor (20 mV/8C on TMP37)
628C Accuracy Over Temperature (typ)
60.58C Linearity (typ)
Stable with Large Capacitive Loads Specified –408C to +1258C, Operation to +1508C Less than 50 mA Quiescent Current Shutdown Current 0.5 mA max Low Self-Heating
APPLICATIONS Environmental Control Systems Thermal Protection Industrial Process Control Fire Alarms Power System Monitors CPU Thermal Management
PRODUCT DESCRIPTION
The TMP35, TMP36 and TMP37 are low voltage, precision centigrade temperature sensors. They provide a voltage output that is linearly proportional to the Celsius (Centigrade) tem­perature. The TMP35/TMP36/TMP37 do not require any external calibration to provide typical accuracies of ±1°C at +25°C and ±2°C over the –40°C to +125°C temperature range.
The low output impedance of the TMP35/TMP36/TMP37, and its linear output and precise calibration simplify interfacing to temperature control circuitry and A/D converters. All three devices are intended for single-supply operation from 2.7 V to 5.5 V maxi­mum. Supply current runs well below 50 µA providing very low self-heating—less than 0.1°C in still air. In addition, a shutdown function is provided to cut supply current to less than 0.5 µA.
The TMP35 is functionally compatible with the LM35/LM45 and provides a 250 mV output at +25°C. The TMP35 reads temperatures from +10°C to +125°C. The TMP36 is speci­fied from –40°C to +125°C, provides a 750 mV output at +25°C and operates to +125°C from a single 2.7 V supply. The TMP36 is functionally compatible with the LM50. Both the TMP35 and TMP36 have an output scale factor of +10 mV/°C. The TMP37 is intended for applications over the range +5°C to +100°C, and provides an output scale factor of 20 mV/°C. The TMP37 provides a 500 mV output at +25°C. Operation extends to +150°C with reduced accuracy for all devices when operating from a 5 V supply.
The TMP35/TMP36/TMP37 are all available in low cost 3-pin TO-92, and SO-8 and 5-pin SOT-23 surface mount packages.
FUNCTIONAL BLOCK DIAGRAM
+Vs (2.7V to 5.5V)
TMP35
SHUTDOWN
TMP36 TMP37
V
OUT
PACKAGE TYPES AVAILABLE
RT-5 (SOT-23)
V
1
OUT
+V
2
S
(Not to Scale)
NC
3
NC = NO CONNECT
TOP VIEW
GND
5
4
SHUTDOWN
SO-8
V
1
OUT
NC
2
(Not to Scale)
3
NC
GND
4
NC = NO CONNECT
TOP VIEW
+V
8
S
7
NC
6
NC
5
SHUTDOWN
TO-92
2
1 3
BOTTOM VIEW
(Not to Scale)
PIN 1 - +Vs, PIN 2 - V
, PIN 3 - GND
OUT
REV. A
Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
(V
= +2.7 V to +5.5 V, –408C TA +1258C
S
1
TMP35/TMP36/TMP37F/G–SPECIFICATIONS
unless otherwise noted)
Parameter Symbol Conditions Min Typ Max Units
ACCURACY
TMP35/TMP36/TMP37F T TMP35/TMP36/TMP37G T
= +25°C ±1 ±2 °C
A
= +25°C ±1 ±3 °C
A
TMP35/TMP36/TMP37F Over Rated Temperature ±2 ±3 °C TMP35/TMP36/TMP37G Over Rated Temperature ±2 ±4 °C Scale Factor, TMP35 +10°C T Scale Factor, TMP36 –40°C T Scale Factor, TMP37 +5°C T
+5°C T
3.0 V +V
Load Regulation 0 µA I Power Supply Rejection Ratio PSRR T
= +25°C 30 100 m°C/V
A
PSRR 3.0 V +V
+125°C +10 +9.8/+10.2 mV/°C
A
+125°C +10 +9.8/+10.2 mV/°C
A
+85°C +20 +19.6/+20.4 mV/°C
A
+100°C +20 +19.6/+20.4 mV/°C
A
5.5 V
S
50 µA120m°C/µA
L
5.5 V 50 m°C/V
S
Linearity 0.5 °C Long-Term Stability T
= +150°C for 1 kHrs 0.4 °C
A
SHUTDOWN
Logic High Input Voltage V Logic Low Input Voltage V
IH IL
VS = 2.7 V 1.8 V VS = 5.5 V 400 mV
OUTPUT
TMP35 Output Voltage T TMP36 Output Voltage T TMP37 Output Voltage T
= +25°C 250 mV
A
= +25°C 750 mV
A
= +25°C 500 mV
A
Output Voltage Range 100 2000 mV Output Load Current I Short-Circuit Current I Capacitive Load Driving C Device Turn-On Time Output within ±1°C 0.5 1 ms
L SC
Note 2 250 µA
L
No Oscillations 100 ki100 pF Load
2
2
050µA
1000 10000 pF
POWER SUPPLY
Supply Range +V Supply Current I Supply Current (Shutdown) I
NOTES
1
Does not consider errors caused by self-heating.
2
Guaranteed but not tested.
Specifications subject to change without notice.
S SY (ON) SY (OFF)
2.7 5.5 V
Unloaded 50 µA Unloaded 0.01 0.5 µA
–2–
REV. A
TMP35/TMP36/TMP37
WAFER TEST LIMITS
(VS = +5 V, GND = O V, TA = +258C, unless otherwise noted)
Parameter Symbol Conditions Min Typ Max Units
ACCURACY
Scale Factor Deviation T Power Supply Rejection Ratio PSRR 2.7 V ≤ +V
= +25°C ±2 °C
A
5.5 V 30 m°C/V
S
SHUTDOWN
Logic High Input Voltage V Logic Low Input Voltage V
IH IL
VS = 2.7 V 1.8 V VS = 5.5 V 400 mV
OUTPUT
TMP35 Output Voltage T TMP36 Output Voltage T TMP37 Output Voltage T Short-Circuit Current I
SC
Device Turn-On Time Output within ±1°C 0.5 1 ms
= +25°C 250 mV
A
= +25°C 750 mV
A
= +25°C 500 mV
A
V
= 5.5 V 250 µA
S
100 ki100 pF Load
1
POWER SUPPLY
Supply Range V+ 2.7 5.5 V Supply Current I Supply Current (Shutdown) I
NOTES Electrical tests are performed at wafer probe to the limits shown. Due to variations in assembly methods and normal yield loss, yield after packaging is not guaranteed for standard product dice. Consult factory to negotiate specifications based on dice lot qualification through sample lot assembly and testing.
1
Guaranteed but not tested.
(ON) Unloaded at +5 V 50 µA
SY
(OFF) Unloaded at +5 V 0.5 µA
SY
DICE CHARACTERISTICS
Die Size 0.027 × 0.030 inch, 810 sq. mils
(0.685 × 0.762 mm, 0.522 sq. mm)
TRANSISTOR COUNT: 25
Substrate is connected to +V
S
1. V
OUT
1 4
32
2. GND
3. SHUTDOWN
4. +V
S
For additional DICE ordering information, refer to databook.
CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the TMP35/TMP36/TMP37 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality.
WARNING!
ESD SENSITIVE DEVICE
REV. A
–3–
TMP35/TMP36/TMP37
SHDN
+V
OUT
+V
S
3X
25µA
2X
Q2 1X
R1
R2
R3
7.5µA
Q3
2X
GND
Q4
Q1
10X
6X
ABSOLUTE MAXIMUM RATINGS*
Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +7 V
Shutdown Pin . . . . . . . . . . . . . . GND
Output Pin . . . . . . . . . . . . . . . . . . . . . . GND # V
SHUTDOWN +V
# +V
OUT
S
S
Operating Temperature Range . . . . . . . . . . –55°C to +150°C
Dice Junction Temperature . . . . . . . . . . . . . . . . . . . . . +175°C
Storage Temperature Range . . . . . . . . . . . . –65°C to +160°C
Lead Temperature (Soldering, 60 sec) . . . . . . . . . . . . +300°C
*CAUTION
1. Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation at or above this specifica­tion is not implied. Exposure to the above maximum rating conditions for extended periods may affect device reliability.
2. Digital inputs are protected; however, permanent damage may occur on unprotected units from high-energy electrostatic fields. Keep units in conductive foam or packaging at all times until ready to use. Use proper antistatic handling procedures.
3. Remove power before inserting or removing units from their sockets.
Package Type u
JA
u
JC
Units
TO-92 (T9 Suffix) 162 120 °C/W SO-8 (S Suffix) 158 43 °C/W SOT-23 (RT Suffix) 300 180 °C/W
θJA is specified for device in socket (worst case conditions).
FUNCTIONAL DESCRIPTION
An equivalent circuit for the TMP3x family of micropower, centigrade temperature sensors is shown in Figure 1. At the heart of the temperature sensor is a bandgap core, which is comprised of transistors Q1 and Q2, biased by Q3 to approxi­mately 8 µA. The bandgap core operates both Q1 and Q2 at the same collector current level; however, since the emitter area of Q1 is 10 times that of Q2, Q1’s V
and Q2’s VBE are not equal
BE
by the following relationship:
A
VBE=Vln
E,Q1
A
E,Q2
ORDERING GUIDE
Accuracy Linear at 258C Operating Package
Model (8C max) Temperature Range Options
TMP35FT9 ±2.0 +10°C to +125°C TO-92 TMP35GT9 ± 3.0 +10°C to +125°C TO-92 TMP35FS ±2.0 +10°C to +125°C SO-8 TMP35GS ±3.0 +10°C to +125°C SO-8 TMP35GRT
2
±3.0 +10°C to +125°C RT-5
TMP36FT9 ±2.0 –40°C to +125°C TO-92 TMP36GT9 ± 3.0 –40°C to +125°C TO-92 TMP36FS ±2.0 –40°C to +125°C SO-8 TMP36GS ±3.0 –40°C to +125°C SO-8 TMP36GRT
2
±3.0 –40°C to +125°C RT-5
TMP37FT9 ±2.0 +5°C to +100°C TO-92 TMP37GT9 ± 3.0 +5°C to +100°C TO-92 TMP37FS ±2.0 +5°C to +100°C SO-8 TMP37GS ±3.0 +5°C to +100°C SO-8 TMP37GRT
NOTES
1
SO = Small Outline; RT = Plastic Surface Mount; TO = Plastic.
2
Consult factory for availability.
2
±3.0 +5°C to +100°C RT-5
1
Figure 1. Temperature Sensor Simplified Equivalent Circuit
Resistors R1 and R2 are used to scale this result to produce the output voltage transfer characteristic of each temperature sensor and, simultaneously, R2 and R3 are used to scale Q1’s V an offset term in V
. Table I summarizes the differences
OUT
between the three temperature sensors’ output characteristics:
Table I. TMP3x Output Characteristics
Offset Output Voltage Output Voltage
Sensor Voltage (V) Scaling (mV/8C) @ 258C
TMP35 0 10 250 mV TMP36 0.5 10 750 mV TMP37 0 20 500 mV
The output voltage of the temperature sensor is available at the emitter of Q4, which buffers the bandgap core and provides load current drive. Q4’s current gain, working with the available base current drive from the previous stage, sets the short-circuit current limit of these devices to 250 µA.
–4–
as
BE
REV. A
TMP35/TMP36/TMP37
FREQUENCY – Hz
100
0.01 20 100k100 1k 10k
31.6
10
3.16
1
0.32
0.1
0.032
POWER SUPPLY REJECTION – 8C/V
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
OUTPUT VOLTAGE – Volts
0.4
0.2
0
250 225 0 25 50 75 100 125
a. TMP35 b. TMP36 c. TMP37
VS = 3V
c
a
TEMPERATURE – 8C
Figure 2. Output Voltage vs. Temperature
5 4 3
a. MAXIMUM LIMIT ( G GRADE )
2 1
0
21 22
ACCURACY ERROR – 8C
23 24
25
0 20 40 60 80 100 120 140
a
b. TYPICAL ACCURACY ERROR c. MINIMUM LIMIT ( G GRADE )
b
c
TEMPERATURE – 8C
Figure 3. Accuracy Error vs. Temperature
b
Figure 5. Power Supply Rejection vs. Frequency
5
MINIMUM SUPPLY VOLTAGE REQUIRED TO MEET
4
DATA SHEET SPECIFICATION NO LOAD
3
b
2
1
MINIMUM SUPPLY VOLTAGE – Volts
a. TMP35/TMP36 b. TMP37
0 250 125225 0 25 50 75 100
TEMPERATURE – 8C
a
Figure 6. Minimum Supply Voltage vs. Temperature
0.4
V+ = +3V to +5.5V, NO LOAD
0.3
0.2
0.1
POWER SUPPLY REJECTION – 8C/V
0 250 125225 0 25 50 75 100
Figure 4. Power Supply Rejection vs. Temperature
REV. A
TEMPERATURE – 8C
–5–
60
a. V+ = 5V
50
40
30
SUPPLY CURRENT – µA
20
10
b. V+ = 3V
NO LOAD
a
b
250 125225 0 25 50 75 100
TEMPERATURE – 8C
Figure 7. Supply Current vs. Temperature
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