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LM74 SPI/Microwire12-Bit Plus Sign Temperature Sensor
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1FEATURES DESCRIPTION
The LM74 is a temperature sensor, Delta-Sigma
2• 0.0625°C Temperature Resolution analog-to-digital converter with an SPI and
• Shutdown Mode Conserves Power Between MICROWIRE compatible interface. The host can
Temperature Reading query the LM74 at any time to read temperature. A
• SPI and MICROWIRE Bus Interface shutdown mode decreases power consumption to
less than 10 μA. This mode is useful in systems
• 5-Bump DSBGA Package Saves Space where low average power consumption is critical.
APPLICATIONS The LM74 has 12-bit plus sign temperature resolution
(0.0625°C per LSB) while operating over a
• System Thermal Management temperature range of −55°C to +150°C.
• Personal Computers The LM74's 3.0V to 5.5V supply voltage range, low
• Disk Drives supply current and simple SPI interface make it ideal
• Office Electronics for a wide range of applications. These include
thermal management and protection applications in
• Electronic Test Equipment hard disk drives, printers, electronic test equipment,
and office electronics. The LM74 is available in the
KEY SPECIFICATIONS SOIC package as well as the 5-Bump DSBGA
• Supply Voltage 3.0V or 2.65V to 5.5V package.
• Supply Current Block Diagram
– Operating
– 265μA (typ)
– 520μA (max)
– Shutdown
– 3μA (typ)
• Temperature Accuracy
–−10°C to 65°C, ±1.25°C(max)
–−25°C to 110°C, ±2.1°C(max)
–−55°C to 125°C, ±3°C(max)
Figure 1.
1Please 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.
2All trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date. Copyright © 2000–2013, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
COP8SA
Micro-
Controller
L0(GPI/O)
SI
SK
CS
SI/O
SC
V+
GND
+3.3 V
0.1 µF
GND (A3)
SC (A2)
SI/O (A1)
(B3) CS
(B1) V+
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Connection Diagram
Figure 2. SOIC – Top View Figure 3. 5-Bump DSBGA – Top View
See Package Number D See Package Number YTA0005
PIN DESCRIPTIONS
SOIC DSBGA
Label Function Typical Connection
Pin # Pin #
Slave Input/Output - Serial bus bi-directional data line.
SI/O 1 1 From and to Controller
Schmitt trigger input.
Slave Clock - Serial bus clock Schmitt trigger input
SC 2 5 From Controller
line.
NC 3 No Connection No Connection
GND 4 4 Power Supply Ground Ground
NC 5 No Connection No Connection
NC 6 No Connection No Connection
CS 7 3 Chip Select input. From Controller
DC Voltage from 3.0V to 5.5V for the LM74CIM
and 2.65V to 5.5V for the LM74CIBP and
V+8 2 Positive Supply Voltage Input LM74CITP. Bypass with a 0.1 μF ceramic
capacitor.
Typical Application
Figure 4. COP Microcontroller Interface
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.
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Absolute Maximum Ratings(1)
Supply Voltage −0.3V to 6.0V
Voltage at any Pin −0.3V to V++ 0.3V
Input Current at any Pin(2) 5 mA
Package Input Current(2) 20 mA
Storage Temperature −65°C to +150°C
ESD Susceptibility(3)
Human Body Model
LM74CIBP and LM74CITP, pin A2 (SC) 1900V
LM74CIM,LM74CIBP, and LM74CITP all other pins 2000V
Machine Model 200V
Soldering process must comply with Reflow Temperature Profile specifications. See www.ti.com/packaging.(4)
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. DC and AC electrical specifications do not
apply when operating the device beyond its rated operating conditions.
(2) When the input voltage (VI) at any pin exceeds the power supplies (VI< GND or VI> +VS) the current at that pin should be limited to 5
mA. The 20 mA maximum package input current rating limits the number of pins that can safely exceed the power supplies with an input
current of 5 mA to four.
(3) Human body model, 100 pF discharged through a 1.5 kΩresistor. Machine model, 200 pF discharged directly into each pin.
(4) Reflow temperature profiles are different for lead-free and non-lead-free packages.
Operating Ratings
Specified Temperature Range TMIN to TMAX
See(1)
LM74CIBP and LM74CITP −40°C to +125°C
LM74CIM −55°C to +150°C
Supply Voltage Range (+VS)
LM74CIBP and LM74CITP +2.65V to +5.5V
LM74CIM +3.0V to +5.5V
(1) The life expectancy of the LM74 will be reduced when operating at elevated temperatures. LM74 θJA (thermal resistance, junction-to-
ambient) when attached to a printed circuit board with 2 oz. foil is summarized as: Device Number LM74CIM Thermal Resistance (θJA)
160°C/W. Device Number LM74CIBP Thermal Resistance (θJA) 250°C/W. Device Number LM74CITP Thermal Resistance (θJA)
250°C/W.
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Temperature-to-Digital Converter Characteristics
Unless otherwise noted, these specifications apply for V+= 2.65V to 3.6V for the LM74CIBP -3, LM74CITP-3, V+= 3.0V to
3.6V for the LM74CIM -3 and V+= 4.5V to 5.5V for the LM74 -5(1).Boldface limits apply for TA= TJ= TMIN to TMAX;all other
limits TA= TJ=+25°C, unless otherwise noted. Typical(2) LM74-5 LM74-3 Units
Parameter Conditions Limits(3) Limits(3) (Limit)
Temperature Error(1) TA=−10°C to +65°C ±1.25 ±1.25 °C (max)
TA=−25°C to +110°C ±2.1 +2.65/−2.15 °C (max)
TA=−40°C to +85°C +2.65/−1.65 ±2.15 °C (max)
TA=−40°C to +110°C +2.65/ +2.65/−2.15 °C (max)
−2.0
TA=−55°C to +125°C ±3.0 ±3.5 °C (max)
TA=−55°C to +150°C ±5.0 ±5.0 °C (max)
Resolution 13 Bits
Temperature SOIC See(4) 280 425 425 ms (max)
Conversion Time DSBGA See(4) 611 925 925 ms (max)
Quiescent Current SOIC Serial Bus Inactive 310 520 520 μA (max)
DSBGA 265 470 470 μA (max)
SOIC Serial Bus Active 310 μA
DSBGA 310 μA
SOIC Shutdown Mode, 7 μA
V+= 3.3V
DSBGA 3 μA
SOIC Shutdown Mode, 8 μA
V+= 5V
DSBGA 4 μA
(1) All SOP (LM74CIM) parts will function over the V+supply voltage range of 3V to 5.5V. All DSBGA (LM74SIBP and LM75CITP) parts will
function over the V+supply voltage range of 2.65V to 5.5V. The SOP (LM74CIM) parts are tested and specified for rated temperature
error at their nominal supply voltage for temperature ranges of −10°C to +65°C, −55°C to +125°C and −55°C to +150°C. For the SOP
(LM74CIM) parts, the temperature error specifications for temperature ranges of −40°C to +85°C, −25°C to +110°C, and −40°C to
+110°C include error induced by power supply variation of ±5% from the nominal value. For the LM74CIM (SOP) parts, the temperature
error will increase by ±0.3°C for a power supply voltage (V+) variation of ±10% from the nominal value.For the LM74CIBP-3 and
LM74CITP-3 (DSBGA) parts all accuracies are ensured over the supply range of 2.65V to 3.6V, except for the temperature ranges of -
55°C to 125°C and −55°C to +150°C where the accuracy applies for the nominal supply voltage of 3.3V. For the LM74CIBP-5 and
LM74CITP-5 (DSBGA) parts all accuracies are guranteed over the supply range of 4.75V to 5.25V, except for the temperature ranges of
-55°C to 125°C and −55°C to +150°C where the accuracy applies for the nominal supply voltage of 5.0V. For the LM74CIBP and
LM74CITP over -55°C to 125°C and −55°C to +150°C, a power supply variation of ±10% will degrade the accuracy by ±0.3°C.
(2) Typicals are at TA= 25°C and represent most likely parametric norm.
(3) Limits are specified to AOQL (Average Outgoing Quality Level).
(4) This specification is provided only to indicate how often temperature data is updated. The LM74 can be read at any time without regard
to conversion state (and will yield last conversion result). A conversion in progress will not be interrupted. The output shift register will be
updated at the completion of the read and a new conversion restarted.
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Logic Electrical Characteristics
DIGITAL DC CHARACTERISTICS
Unless otherwise noted, these specifications apply for V+= 2.65V to 3.6V for the LM74CIBP -3, LM74CITP-3, V+= 3.0V to
3.6V for the LM74CIM -3 and V+= 4.5V to 5.5V for the LM74 -5(1).Boldface limits apply for TA= TJ= TMIN to TMAX;all other
limits TA= TJ=+25°C, unless otherwise noted. Typical(2) Limits(3) Units
Symbol Parameter Conditions (Limit)
VIN(1) Logical “1” Input Voltage V+× 0.7 V (min)
V++ 0.3 V (max)
VIN(0) Logical “0” Input Voltage −0.3 V (min)
V+× 0.3 V (max)
Input Hysteresis Voltage V+= 3.0V to 3.6V 0.8 0.35 V (min)
V+= 4.5V to 5.5V 0.8 0.33 V (min)
IIN(1) Logical “1” Input Current VIN = V+0.005 3.0 μA (max)
IIN(0) Logical “0” Input Current VIN = 0V −0.005 −3.0 μA (min)
CIN All Digital Inputs 20 pF
VOH High Level Output Voltage IOH =−400 μA2.4 V (min)
VOL Low Level Output Voltage IOL = +2 mA 0.4 V (max)
IO_TRI-STATE TRI-STATE Output Leakage Current VO= GND −1μA (min)
VO= V++1 μA
(max)
(1) All SOP (LM74CIM) parts will function over the V+supply voltage range of 3V to 5.5V. All DSBGA (LM74SIBP and LM75CITP) parts will
function over the V+supply voltage range of 2.65V to 5.5V. The SOP (LM74CIM) parts are tested and specified for rated temperature
error at their nominal supply voltage for temperature ranges of −10°C to +65°C, −55°C to +125°C and −55°C to +150°C. For the SOP
(LM74CIM) parts, the temperature error specifications for temperature ranges of −40°C to +85°C, −25°C to +110°C, and −40°C to
+110°C include error induced by power supply variation of ±5% from the nominal value. For the LM74CIM (SOP) parts, the temperature
error will increase by ±0.3°C for a power supply voltage (V+) variation of ±10% from the nominal value.For the LM74CIBP-3 and
LM74CITP-3 (DSBGA) parts all accuracies are ensured over the supply range of 2.65V to 3.6V, except for the temperature ranges of -
55°C to 125°C and −55°C to +150°C where the accuracy applies for the nominal supply voltage of 3.3V. For the LM74CIBP-5 and
LM74CITP-5 (DSBGA) parts all accuracies are guranteed over the supply range of 4.75V to 5.25V, except for the temperature ranges of
-55°C to 125°C and −55°C to +150°C where the accuracy applies for the nominal supply voltage of 5.0V. For the LM74CIBP and
LM74CITP over -55°C to 125°C and −55°C to +150°C, a power supply variation of ±10% will degrade the accuracy by ±0.3°C.
(2) Typicals are at TA= 25°C and represent most likely parametric norm.
(3) Limits are specified to AOQL (Average Outgoing Quality Level).
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SERIAL BUS DIGITAL SWITCHING CHARACTERISTICS
Unless otherwise noted, these specifications apply for V+= 2.65V to 3.6V for the LM74CIBP -3, LM74CITP-3, V+= 3.0V to
3.6V for the LM74CIM -3 and V+= 4.5V to 5.5V for the LM74 -5(1); CL(load capacitance) on output lines = 100 pF unless
otherwise specified. Boldface limits apply for TA= TJ= TMIN to TMAX;all other limits TA= TJ= +25°C, unless otherwise
noted. Typical(2) Limits(3) Units
Symbol Parameter Conditions (Limit)
t1SC (Clock) Period 0.16 μs (min)
DC (max)
t2CS Low to SC (Clock) High Set-Up Time 100 ns (min)
t3CS Low to Data Out (SO) Delay 70 ns (max)
t4SC (Clock) Low to Data Out (SO) Delay 100 ns (max)
t5CS High to Data Out (SO) TRI-STATE 200 ns (max)
t6SC (Clock) High to Data In (SI) Hold Time 50 ns (min)
t7Data In (SI) Set-Up Time to SC (Clock) High 30 ns (min)
(1) All SOP (LM74CIM) parts will function over the V+supply voltage range of 3V to 5.5V. All DSBGA (LM74SIBP and LM75CITP) parts will
function over the V+supply voltage range of 2.65V to 5.5V. The SOP (LM74CIM) parts are tested and specified for rated temperature
error at their nominal supply voltage for temperature ranges of −10°C to +65°C, −55°C to +125°C and −55°C to +150°C. For the SOP
(LM74CIM) parts, the temperature error specifications for temperature ranges of −40°C to +85°C, −25°C to +110°C, and −40°C to
+110°C include error induced by power supply variation of ±5% from the nominal value. For the LM74CIM (SOP) parts, the temperature
error will increase by ±0.3°C for a power supply voltage (V+) variation of ±10% from the nominal value.For the LM74CIBP-3 and
LM74CITP-3 (DSBGA) parts all accuracies are ensured over the supply range of 2.65V to 3.6V, except for the temperature ranges of -
55°C to 125°C and −55°C to +150°C where the accuracy applies for the nominal supply voltage of 3.3V. For the LM74CIBP-5 and
LM74CITP-5 (DSBGA) parts all accuracies are guranteed over the supply range of 4.75V to 5.25V, except for the temperature ranges of
-55°C to 125°C and −55°C to +150°C where the accuracy applies for the nominal supply voltage of 5.0V. For the LM74CIBP and
LM74CITP over -55°C to 125°C and −55°C to +150°C, a power supply variation of ±10% will degrade the accuracy by ±0.3°C.
(2) Typicals are at TA= 25°C and represent most likely parametric norm.
(3) Limits are specified to AOQL (Average Outgoing Quality Level).
Figure 5. Data Output Timing Diagram
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-55°C
-25°C
-0.0625°C
0°C
0,0001,1001,0000 +0.0625°C
+25°C
Temperature
+150°C
Output Code
1,1111,1111,1111
1,1110,0111,0000
1,1100,1001,0000
00,0000,0000,0000
0,0000,0000,0001
0,1001,0110,0000
LM74
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Electrical Characteristics
Figure 8. Temperature-to-Digital Transfer Function (Non-linear scale for clarity)
TRI-STATE Test Circuit
Figure 9.
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Typical Performance Characteristics
Average Power-On Reset Voltage vs Temperature Static Supply Current vs Temperature (SOIC)
Figure 10. Figure 11.
Static Supply Current vs Temperature (DSBGA) Temperature Error (SOIC)
Figure 12. Figure 13.
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FUNCTIONAL DESCRIPTION
The LM74 temperature sensor incorporates a band-gap type temperature sensor and 12-bit plus sign ΔΣ ADC
(Delta-Sigma Analog-to-Digital Converter). Compatibility of the LM74's three wire serial interface with SPI and
MICROWIRE allows simple communications with common microcontrollers and processors. Shutdown mode can
be used to optimize current drain for different applications. A Manufacture's/Device ID register identifies the
LM74 as Texas Instruments product.
Power Up and Power Down
When the supply voltage is less than about 1.6V (typical), the LM74 is considered powered down. The LM74
always powers up in a known state. When the supply voltage rises above 1.6V (typical), an internal Power-On
Reset (POR) occurs and the temperature register will then contain a value of 1111 1111 0000 00XX, where XX
indicates undefined values. See Temperature Register (after power-up, before first complete temperature
conversion) diagram for contents after POR but before completion of the first temperature conversion.
The LM74 power-up default condition is continuous conversion mode. After completion of the first full
temperature conversion, the register will contain temperature measurement data in bits D15 (the temperature
data MSB) through D3 (the temperature data LSB). Bit D2 will be fixed high; bits D1 and D0 are undefined. See
Section 1.5.3 for a diagram of the Temperature Regisiter contents after the first complete temperature
conversion. Note that bit D2 represents a complete conversion flag. During POR it is low and, after the first
temperature conversion is complete, it goes high. This bit can be polled to indicate when the POR data in the
Temperature Register has been replaced with valid temperature data.
After the first conversion, and any subsequent conversions, the value in the temperature register does not
change until the completion of the next conversion, at which time the temperature register is updated with the
latest temperature value.
Serial Bus Interface
The LM74 operates as a slave and is compatible with SPI or MICROWIRE bus specifications. Data is clocked
out on the falling edge of the serial clock (SC), while data is clocked in on the rising edge of SC. A complete
transmit/receive communication will consist of 32 serial clocks. The first 16 clocks comprise the transmit phase of
communication, while the second 16 clocks are the receive phase.
When CS is high SI/O will be in TRI-STATE. Communication should be initiated by taking chip select (CS) low.
This should not be done when SC is changing from a low to high state. Once CS is low the serial I/O pin (SI/O)
will transmit the first bit of data. The master can then read this bit with the rising edge of SC. The remainder of
the data will be clocked out by the falling edge of SC. Once the 14 bits of data (one sign bit, twelve temperature
bits and 1 high bit) are transmitted the SI/O line will go into TRI-STATE. CS can be taken high at any time during
the transmit phase. If CS is brought low in the middle of a conversion the LM74 will complete the conversion and
the output shift register will be updated after CS is brought back high.
The receive phase of a communication starts after 16 SC periods. CS can remain low for 32 SC cycles. The
LM74 will read the data available on the SI/O line on the rising edge of the serial clock. Input data is to an 8-bit
shift register. The part will detect the last eight bits shifted into the register. The receive phase can last up to 16
SC periods. All ones must be shifted in order to place the part into shutdown. A zero in any location will take the
LM74 out of shutdown. The following codes should only be transmitted to the LM74:
• 00 hex
• 01 hex
• 03 hex
• 07 hex
• 0F hex
• 1F hex
• 3F hex
• 7F hex
• FF hex
any others may place the part into a Test Mode. Test Modes are used by Texas Instruments to thoroughly test
the function of the LM74 during production testing. Only eight bits have been defined above since only the last
eight transmitted are detected by the LM74, before CS is taken HIGH.
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The following communication can be used to determine the Manufacturer's/Device ID and then immediately place
the part into continuous conversion mode. With CS continuously low:
• Read 16 bits of temperature data
• Write 16 bits of data commanding shutdown
• Read 16 bits of Manufacture's/Device ID data
• Write 8 to 16 bits of data commanding Conversion Mode
• Take CS HIGH.
Note that one complete temperature conversion period will have to pass before the LM74 Temperature register
will contain the new temperature data. Until then, it will contain a "stale" temperature (the data that was in the
register before going into shutdown mode).
Temperature Data Format
Temperature data is represented by a 13-bit, two's complement word with an LSB (Least Significant Bit) equal to
0.0625°C:
Temperature Digital Output
Binary Hex
+150°C 0100 1011 0000 0111 4B 07h
+125°C 0011 1110 1000 0111 3E 87h
+25°C 0000 1100 1000 0111 0C 87h
+0.0625°C 0000 0000 0000 1111 00 0Fh
0°C 0000 0000 0000 0111 00 07h
−0.0625°C 1111 1111 1111 1111 FF FFh
−25°C 1111 0011 1000 0111 F3 87h
−55°C 1110 0100 1000 0111 E4 87h
Note: The last two bits are TRI-STATE and depicted as one in the table.
The first data byte is the most significant byte with most significant bit first, permitting only as much data as
necessary to be read to determine temperature condition. For instance, if the first four bits of the temperature
data indicate an overtemperature condition, the host processor could immediately take action to remedy the
excessive temperatures.
Shutdown Mode/Manufacturer's ID
Shutdown mode is enabled by writing XX FF to the LM74 as shown in Figure 16c. The serial bus is still active
when the LM74 is in shutdown. Current draw drops to less than 10 μA between serial communications. When in
shutdown mode the LM74 always will output 1000 0000 0000 00XX. This is the manufacturer's/Device ID
information. The first 5-bits of the field (1000 0XXX) are reserved for manufacturer's ID. As mentioned in Section
1.2, writing a zero to the LM74 configuration register will take it out of shutdown mode and place it in conversion
mode. In other words, any valid code listed in Section 1.2 other than XX FF will put it in conversion mode. After
leaving shutdown, but before the first temperature conversion is complete, the temperature register will contain
the last measured temperature which resided in the temperature register before entering shutdown mode. After
the completion of the first conversion, the temperature register will be updated with the new temperature data.
Internal Register Structure
The LM74 has three registers, the temperature register, the configuration register and the manufacturer's/device
identification register. The temperature and manufacturer's/device identification registers are read only. The
configuration register is write only.
Configuration Register
(Selects shutdown or continuous conversion modes):
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Table 1. (Write Only):
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
X X X X X X X X Shutdown
D0–D15 set to XX FF hex enables shutdown mode.
D0–D15 set to 00 00 hex sets Continuous conversion mode.
Note: setting D0-D15 to any other values may place the LM74 into a manufacturer's test mode, upon which the
LM74 will stop responding as described. These test modes are to be used for Texas Instruments production
testing only. See Serial Bus Interface for a complete discussion.
Temperature Register (after power-up, before first complete temperature conversion)
Table 2. (Read Only):
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
11111111000000XX
D0–D1: Undefined. TRI-STATE will be output on SI/0.
D2–D15: Power-on Reset (POR) values.
Temperature Register (after completion of first temperature conversion)
Table 3. (Read Only):
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
MSB Bit 11 Bit 10 Bit 9 Bit 8 Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 LSB 1 X X
D0–D1: Undefined. TRI-STATE will be output on SI/0.
D2: High.
D3–D15: Temperature Data. One LSB = 0.0625°C. Two's complement format.
Manufacturer's Device ID Register
Table 4. (Read Only):
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
10000000000000XX
D0–D1: Undefined. TRI-STATE will be output on SI/0.
D2–D15: Manufacturer's/Device ID Data. This register is accessed whenever the LM74 is in shutdown mode.
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Serial Bus Timing Diagrams
Figure 14. a) Reading Continuous Conversion - Single Eight-Bit Frame
Figure 15. b) Reading Continuous Conversion - Two Eight-Bit Frames
Figure 16. c) Writing Shutdown Control
Application Hints
To get the expected results when measuring temperature with an integrated circuit temperature sensor like the
LM74, it is important to understand that the sensor measures its own die temperature. For the LM74, the best
thermal path between the die and the outside world is through the LM74's pins. In the SOIC package all the pins
on the LM74 will have an equal effect on the die temperature. Because the pins represent a good thermal path to
the LM74 die, the LM74 will provide an accurate measurement of the temperature of the printed circuit board on
which it is mounted. There is a less efficient thermal path between the plastic package and the LM74 die. If the
ambient air temperature is significantly different from the printed circuit board temperature, it will have a small
effect on the measured temperature.
In probe-type applications, the LM74 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 LM74 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. Printed-circuit coatings and varnishes such as
Humiseal and epoxy paints or dips are often used to insure that moisture cannot corrode the LM74 or its
connections.
DSBGA Light Sensitivity
The LM74 in the DSBGA package should not be exposed to ultraviolet light. The DSBGA package does not
completely encapsulate the LM74 die in epoxy. Exposing the LM74 DSBGA package to bright sunlight will not
immediatly cause a change in the output reading. Our experiments show that directly exposing the circuit side
(bump side) of the die to high intensity (≥1mW/cm2) ultraviolet light, centered at a wavelength of 254nm, for
greater than 20 minutes will deprogram the EEPROM cells in the LM74. Since the EEPROM is used for storing
calibration coefficients, the LM74 will function but the temperature accuracy will no longer be as specified. Light
can penetrate through the side of the package as well, so exposure to ultra violet radiation is not recommended
even after mounting.
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Typical Applications
Figure 17. Temperature monitor using Intel 196 processor
Figure 18. LM74 digital input control using microcontroller's general purpose I/O.
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SNIS107K –MAY 2000–REVISED MARCH 2013
REVISION HISTORY
Changes from Revision J (March 2013) to Revision K Page
• Changed layout of National Data Sheet to TI format .......................................................................................................... 14
Copyright © 2000–2013, Texas Instruments Incorporated Submit Documentation Feedback 15
Product Folder Links: LM74
PACKAGE OPTION ADDENDUM
www.ti.com 10-Dec-2020
Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status
(1)
Package Type Package
Drawing Pins Package
Qty Eco Plan
(2)
Lead finish/
Ball material
(6)
MSL Peak Temp
(3)
Op Temp (°C) Device Marking
(4/5)
Samples
LM74CIM-3 NRND SOIC D 8 95 Non-RoHS &
Non-Green Call TI Call TI -55 to 150 LM74
CIM3
LM74CIM-3/NOPB ACTIVE SOIC D 8 95 RoHS & Green SN Level-1-260C-UNLIM -55 to 150 LM74
CIM3
LM74CIM-5 NRND SOIC D 8 95 Non-RoHS &
Non-Green Call TI Call TI -55 to 150 LM74
CIM5
LM74CIM-5/NOPB ACTIVE SOIC D 8 95 RoHS & Green SN Level-1-260C-UNLIM -55 to 150 LM74
CIM5
LM74CIMX-3 NRND SOIC D 8 2500 Non-RoHS &
Non-Green Call TI Call TI -55 to 150 LM74
CIM3
LM74CIMX-3/NOPB ACTIVE SOIC D 8 2500 RoHS & Green SN Level-1-260C-UNLIM -55 to 150 LM74
CIM3
LM74CIMX-5/NOPB ACTIVE SOIC D 8 2500 RoHS & Green SN Level-1-260C-UNLIM -55 to 150 LM74
CIM5
LM74CITP-3/NOPB ACTIVE DSBGA YTA 5 250 RoHS & Green SNAGCU Level-1-260C-UNLIM -40 to 125 10
LM74CITPX-3/NOPB ACTIVE DSBGA YTA 5 3000 RoHS & Green SNAGCU Level-1-260C-UNLIM -40 to 125 10
(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 <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
PACKAGE OPTION ADDENDUM
www.ti.com 10-Dec-2020
Addendum-Page 2
(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 finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two
lines if the finish value exceeds the maximum column width.
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.
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device Package
Type Package
Drawing Pins SPQ Reel
Diameter
(mm)
Reel
Width
W1 (mm)
A0
(mm) B0
(mm) K0
(mm) P1
(mm) W
(mm) Pin1
Quadrant
LM74CIMX-3 SOIC D 8 2500 330.0 12.4 6.5 5.4 2.0 8.0 12.0 Q1
LM74CIMX-3/NOPB SOIC D 8 2500 330.0 12.4 6.5 5.4 2.0 8.0 12.0 Q1
LM74CIMX-5/NOPB SOIC D 8 2500 330.0 12.4 6.5 5.4 2.0 8.0 12.0 Q1
LM74CITP-3/NOPB DSBGA YTA 5 250 178.0 8.4 1.7 1.7 0.76 4.0 8.0 Q1
LM74CITPX-3/NOPB DSBGA YTA 5 3000 178.0 8.4 1.7 1.7 0.76 4.0 8.0 Q1
PACKAGE MATERIALS INFORMATION
www.ti.com 29-Sep-2019
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
LM74CIMX-3 SOIC D 8 2500 367.0 367.0 35.0
LM74CIMX-3/NOPB SOIC D 8 2500 367.0 367.0 35.0
LM74CIMX-5/NOPB SOIC D 8 2500 367.0 367.0 35.0
LM74CITP-3/NOPB DSBGA YTA 5 250 210.0 185.0 35.0
LM74CITPX-3/NOPB DSBGA YTA 5 3000 210.0 185.0 35.0
PACKAGE MATERIALS INFORMATION
www.ti.com 29-Sep-2019
Pack Materials-Page 2
www.ti.com
PACKAGE OUTLINE
C
.228-.244 TYP
[5.80-6.19]
.069 MAX
[1.75]
6X .050
[1.27]
8X .012-.020
[0.31-0.51]
2X
.150
[3.81]
.005-.010 TYP
[0.13-0.25]
0 - 8 .004-.010
[0.11-0.25]
.010
[0.25]
.016-.050
[0.41-1.27]
4X (0 -15 )
A
.189-.197
[4.81-5.00]
NOTE 3
B .150-.157
[3.81-3.98]
NOTE 4
4X (0 -15 )
(.041)
[1.04]
SOIC - 1.75 mm max heightD0008A
SMALL OUTLINE INTEGRATED CIRCUIT
4214825/C 02/2019
NOTES:
1. Linear dimensions are in inches [millimeters]. Dimensions in parenthesis are for reference only. Controlling dimensions are in inches.
Dimensioning and tolerancing per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not
exceed .006 [0.15] per side.
4. This dimension does not include interlead flash.
5. Reference JEDEC registration MS-012, variation AA.
18
.010 [0.25] C A B
5
4
PIN 1 ID AREA
SEATING PLANE
.004 [0.1] C
SEE DETAIL A
DETAIL A
TYPICAL
SCALE 2.800
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EXAMPLE BOARD LAYOUT
.0028 MAX
[0.07]
ALL AROUND
.0028 MIN
[0.07]
ALL AROUND
(.213)
[5.4]
6X (.050 )
[1.27]
8X (.061 )
[1.55]
8X (.024)
[0.6]
(R.002 ) TYP
[0.05]
SOIC - 1.75 mm max heightD0008A
SMALL OUTLINE INTEGRATED CIRCUIT
4214825/C 02/2019
NOTES: (continued)
6. Publication IPC-7351 may have alternate designs.
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.
METAL SOLDER MASK
OPENING
NON SOLDER MASK
DEFINED
SOLDER MASK DETAILS
EXPOSED
METAL
OPENING
SOLDER MASK METAL UNDER
SOLDER MASK
SOLDER MASK
DEFINED
EXPOSED
METAL
LAND PATTERN EXAMPLE
EXPOSED METAL SHOWN
SCALE:8X
SYMM
1
45
8
SEE
DETAILS
SYMM
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EXAMPLE STENCIL DESIGN
8X (.061 )
[1.55]
8X (.024)
[0.6]
6X (.050 )
[1.27] (.213)
[5.4]
(R.002 ) TYP
[0.05]
SOIC - 1.75 mm max heightD0008A
SMALL OUTLINE INTEGRATED CIRCUIT
4214825/C 02/2019
NOTES: (continued)
8. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
9. Board assembly site may have different recommendations for stencil design.
SOLDER PASTE EXAMPLE
BASED ON .005 INCH [0.125 MM] THICK STENCIL
SCALE:8X
SYMM
SYMM
1
45
8
MECHANICAL DATA
YTA0005xxx
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TPD05XXX (Rev A)
0.500±0.075
D
E
4215103/A 12/12
A
. All linear dimensions are in millimeters. Dimensioning and tolerancing per ASME Y14.5M-1994.
B. This drawing is subject to change without notice.
NOTES:
D: Max =
E: Max =
1.667 mm, Min =
1.616 mm, Min =
1.606 mm
1.555 mm
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