TMP125
SBOS323A − DECEMBER 2004 − REVISED JUNE 2005
2°C Accurate Digital Temperature Sensor
with SPI Interface
FEATURES
DESCRIPTION
D DIGITAL OUTPUT: SPI-Compatible Interface
D RESOLUTION: 10-Bit, 0.25°C
D ACCURACY:
The TMP125 is an SPI-compatible temperature sensor
available in the tiny SOT23-6 package. Requiring no
external components, the TMP125 is capable of
measuring temperatures within 2°C of accuracy over a
temperature range of −25°C to +85°C and 2.5°C of
accuracy over −40°C to +125°C. Low supply current, and
a supply range from 2.7V to 5.5V, make the TMP125 an
excellent candidate for low-power applications.
±2.0°C (max) from −25°C to +85°C
±2.5°C (max) from −40°C to +125°C
D
D
D
D
LOW QUIESCENT CURRENT: 50µA (max)
WIDE SUPPLY RANGE: 2.7V to 5.5V
The TMP125 is ideal for extended thermal measurement
in a variety of communication, computer, consumer,
environmental,
industrial,
and
instrumentation
applications.
TINY SOT23-6 PACKAGE
OPERATION FROM −40°C to +125°C
APPLICATIONS
D BASE STATION EQUIPMENT
D COMPUTER PERIPHERAL THERMAL
Temperature
PROTECTION
D
D
D
D
NOTEBOOK COMPUTERS
GND
1
Diode
Temp.
Sensor
Control
Logic
6
SO
SI
2
∆Σ
A/D
Converter
Serial
Interface
5
CS
V+
3
OSC
Config.
and Temp.
Register
4
SCK
DATA ACQUISITION SYSTEMS
TELECOM EQUIPMENT
OFFICE MACHINES
TMP125 RELATED PRODUCTS
FEATURES
PRODUCT
2°C Digital Temp Sensors with Two-Wire Interface
TMP100/101
1.5°C Digital Temp Sensors with Two-Wire Interface
TMP75/175
1.5°C Digital Temp Sensors with SPI
TMP121/123
1.5°C Programmable Digital Temp Sensors with SPI
TMP122/124
TMP125
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments
semiconductor products and disclaimers thereto appears at the end of this data sheet.
SPI is a registered trademark of Motorola. All other trademarks are the property of their respective owners.
Copyright 2004−2005, Texas Instruments Incorporated
! !
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SBOS323A − DECEMBER 2004 − REVISED JUNE 2005
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.
ABSOLUTE MAXIMUM RATINGS(1)
Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +7V
Input Voltage(2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3V to +7V
Input Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±10mA
Output Short Circuit(3) . . . . . . . . . . . . . . . . . . . . . . . . . . Continuous
Operating Temperature Range . . . . . . . . . . . . . . . −55°C to +125°C
Storage Temperature Range . . . . . . . . . . . . . . . . . −60°C to +150°C
Junction Temperature (TJ max) . . . . . . . . . . . . . . . . . . . . . . +150°C
Lead Temperature (soldering) . . . . . . . . . . . . . . . . . . . . . . . . +300°C
ESD Rating (Human Body Model) . . . . . . . . . . . . . . . . . . . . 4000V
(Charged Device Model) . . . . . . . . . . . . . . . . . 1000V
(1) Stresses above these ratings may cause permanent damage.
Exposure to absolute maximum conditions for extended periods
may degrade device reliability. These are stress ratings only, and
functional operation of the device at these or any other conditions
beyond those specified is not supported.
(2) Input terminals are diode-clamped to the power-supply rails.
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.
Input signals that can swing more than 0.5V beyond the supply
rails should be current limited to 10mA or less.
(3) Short-circuit to ground.
ORDERING INFORMATION(1)
PRODUCT
PACKAGE-LEAD
PACKAGE DESIGNATOR
TMP125
SOT23-6
DBV
PACKAGE MARKING
T125
(1) For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI web site
at www.ti.com.
PIN CONFIGURATION
Top View
TMP125
1
SI
2
V+
3
T125
GND
6
SO
5
CS
4
SCK
SOT23−6
NOTE: Pin 1 is determined by orienting
the package marking as shown.
2
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SBOS323A − DECEMBER 2004 − REVISED JUNE 2005
ELECTRICAL CHARACTERISTICS
At TA = −40°C to +125°C and VS = +2.7V to 5.5V, unless otherwise noted.
TMP125
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNIT
TEMPERATURE INPUT
+125
°C
−25°C to +85°C
±0.5
±2.0
°C
−40°C to +125°C
±1.0
±2.5
Range
−40
Accuracy (temperature error)
°C
Resolution
10
Bits
Temperature Measurement Noise
0.1
LSB
DIGITAL INPUT/OUTPUT
Input Logic Levels:
VIH
VIL
Input Current, SI, SCK, CS
0.7(V+)
IIN
V
0V = VIN = V+
0.3(V+)
V
±1
µA
0.4
V
Output Logic Levels:
VOL SO
VOH SO
ISINK = 3mA
ISOURCE = 2mA
(V+)−0.4
Input Capacitance, SI, SCK, CS
Conversion Time
10-Bit
Update Rate
V
2.5
pF
60
ms
120
ms
POWER SUPPLY
Operating Range
Quiescent Current, at TA = 25°C
2.7
IQ
over Temperature
Serial Bus Inactive
36
−40°C to +125°C
Shutdown Current
0.1
over Temperature
5.5
V
50
µA
60
µA
1
µA
1
µA
TEMPERATURE RANGE
Specified Range
−40
+125
°C
Operating Range
−55
+125
°C
Storage Range
−60
+150
Thermal Resistance
qJA
SOT23-6 Surface-Mount
200
°C
°C/W
3
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SBOS323A − DECEMBER 2004 − REVISED JUNE 2005
TYPICAL CHARACTERISTICS
At TA = −40°C to +125°C and VS = +2.7V to 5.5V, unless otherwise noted.
CONVERSION TIME vs TEMPERATURE
QUIESCENT CURRENT vs TEMPERATURE
80
45
VS = 5.5V
Conversion Time (ms)
40
IQ (µA)
VS = 5.5V
75
35
30
70
65
60
55
50
25
Active Conversion
Serial Bus Inactive
20
45
5 Typical Units Shown
40
−55
−35
−15
5
25
45
65
85
105
−55
125
−35
−15
5
TEMPERATURE ACCURACY vs TEMPERATURE
2.0
Temperature Error (_ C)
1.5
1.0
0.5
0.0
−0.5
−1.0
−1.5
−35
−15
5
25
45
65
Temperature (_C)
4
45
65
Temperature (_ C)
Temperature (_ C)
−2.0
−55
25
85
105
125
85
105
125
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SBOS323A − DECEMBER 2004 − REVISED JUNE 2005
APPLICATIONS
The TMP125 10-bit, read-only digital temperature sensor
is optimal for thermal management and thermal protection
applications. The TMP125 is specified for a temperature
range of −40°C to +125°C, with operation extending down
to −55°C. It is specified for a supply voltage range of 2.7V
to 5.5V, and also features a hardware shutdown to provide
power savings. Quiescent current is reduced to 1µA during
analog shutdown.
The TMP125 communicates through a serial interface that
is SPI-compatible. Temperature is converted to a 10-bit
data word with 0.25°C resolution. The TMP125 is optimal
for low-power applications, with a 120ms conversion
period for reduced power consumption.
The sensing device of the TMP125 is the chip itself.
Thermal paths run through the package leads as well as
the plastic package, and the lower thermal resistance of
metal causes the leads to provide the primary thermal
path.
The TMP125 requires no external components for
operation, though a 0.1µF supply bypass capacitor is
recommended. Figure 1 shows typical connection for the
TMP125.
0.1µF
3
4
SO
6
The one-shot command can be used to force a single
conversion. When the command is issued, the part will
perform a single conversion and then go into shutdown
mode. After the conversion is complete, the conversion
result should be read with the power-down bit high (see
Figure 3) if you do not want to start a new conversion.
The TMP125 will go into idle mode for 60ms, requiring only
20µA of current. A new conversion begins every 120ms.
Figure 2 describes the conversion timing for the TMP125.
TEMPERATURE REGISTER
The Temperature Register of the TMP125 is a 16-bit,
read-only register that stores the output of the most recent
conversion. However, temperature is represented by only
10-bits, which are in signed two’s complement format. The
first bit of the Temperature Register, D15, is a leading zero.
Bits D14 and D5 are used to indicate temperature. Bits D4
to D0 are the same as D5 (see Table 1). Data format for
temperature is summarized in Table 2. When calculating
the signed two’s complement temperature value, be sure
to use only the 10 data bits.
Following power-up or reset, the Temperature Register will
read 0°C until the first conversion is complete.
V+
SCK
shutdown, perform a 16-clock communication with SI set
to logic low. The 16-clock communication is the same as
the Data Read shown in Figure 3, except that the data on
SO will be the last conversion prior to putting the device
into shutdown mode. Note that SO is only used to control
the shutdown function; if not using this function, connect
this pin to ground.
2
D14
D13
D12
D11
D10
D9
D8
0
T9
T8
T7
T6
T5
T4
T3
D7
D6
D5
D4
D3
D2
D1
D0
T2
T1
T0
T0
T0
T0
T0
T0
SI
TMP125
5
D15
CS
Table 1. Temperature Register
1
TEMPERATURE
(°C)
Figure 1. Typical Connections for the TMP125
DIGITAL OUTPUT
D14…D5
+127
01 1111 1100
+125
01 1111 0100
+100
01 1001 0000
COMMUNICATING WITH THE TMP125
+75
01 0010 1100
The TMP125 continuously converts temperatures to
digital data. Temperature data is read by pulling CS low.
Once CS is pulled low, temperature data from the last
completed conversion prior to dropping CS is latched into
the shift register and clocked out at SO on the falling SCK
edge. The 16-bit data word is clocked out sign bit first,
followed by the MSB. The SI pin is used to put the device
into shutdown mode. To enter shutdown mode, SI must be
high on the rising edge of the third bit of SCK (see
Figure 3). Also, all 16 bits must be clocked to allow
shutdown on the TMP125. To bring the device out of
+50
00 1100 1000
+25
00 0110 0100
+10
00 0010 1000
+0.25
00 0000 0001
0
00 0000 0000
−0.25
11 1111 1111
−25
11 1001 1100
−50
11 0011 1000
−55
11 0010 0100
Table 2. Temperature Data Format
5
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SBOS323A − DECEMBER 2004 − REVISED JUNE 2005
Timing Diagrams
The TMP125 is SPI-compatible. Figure 3 and Figure 4
describe the output data of the TMP125. Figure 5,
Figure 6, and Figure 7 describe the various timing
requirements, with parameters defined in Table 3.
120ms
60ms
50µA (active)
PARAMETER
20µA (idle)
MIN
SCK Period
Data In to Rising Edge SCK Setup Time
SCK Falling Edge to Output Data Delay
SCK Rising Edge to Input Data Hold Time
CS to Rising Edge SCK Set-Up Time
t1
t2
t3
t4
CS to Output Data Delay
t5
t6
CS Rising Edge to Output High Impedance
t7
Figure 2. Conversion Time and Period
MAX
UNITS
100
ns
20
ns
30
ns
20
ns
40
ns
30
ns
30
ns
Table 3. Timing Description
CS
SCK
SO
Leading
Zero
SI
Don’t
Care
T9
T8
Don’t
Care
Power
Down
T7
T6
T5
T4
T3
T2
T1
T0
T0
T0
T0
T0
T0
To enter shutdown mode, SI must be high on the rising edge of the third bit of SCK (see the Communicating with the TMP125 section).
Figure 3. Data READ
CS
SCK
SO
Leading
Zero
SI
Don’t
Care
T9
T8
T7
Don’t
Care
Power
Down
One−
Shot
T6
T5
T4
T3
T2
T1
Figure 4. One-Shot Command
6
T0
T0
T0
T0
T0
T0
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SBOS323A − DECEMBER 2004 − REVISED JUNE 2005
SCK
SCK
t2
t2
t4
t4
CS
CS
SO
SO
Figure 5. Input Data Timing Diagram
SCK
t5
t1
t3
CS
t6
SO
Figure 6. Output Data Timing Diagram
SCK
SCK
CS
CS
t7
t7
SI
SI
Figure 7. High Impedance Output Timing Diagram
7
PACKAGE OPTION ADDENDUM
www.ti.com
15-Jul-2022
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)
Samples
(4/5)
(6)
HPA00444AIDBVT
ACTIVE
SOT-23
DBV
6
250
TBD
Call TI
Call TI
-40 to 125
TMP125AIDBVR
ACTIVE
SOT-23
DBV
6
3000
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
T125
Samples
TMP125AIDBVRG4
ACTIVE
SOT-23
DBV
6
3000
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
T125
Samples
TMP125AIDBVT
ACTIVE
SOT-23
DBV
6
250
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
T125
Samples
TMP125AIDBVTG4
ACTIVE
SOT-23
DBV
6
250
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
T125
Samples
Samples
(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