SNOS808P January   2000  – December 2014 LM75A

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Temperature-to-Digital Converter Characteristics
    6. 6.6 Digital DC Characteristics
    7. 6.7 I2C Digital Switching Characteristics
    8. 6.8 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Digital Temperature Sensor
    4. 7.4 Device Functional Modes
    5. 7.5 Programming
      1. 7.5.1 I2C Bus Interface
      2. 7.5.2 Temperature Data Format
      3. 7.5.3 Shutdown Mode
      4. 7.5.4 Fault Queue
      5. 7.5.5 Comparator and Interrupt Mode
      6. 7.5.6 O.S. Output
      7. 7.5.7 O.S. Polarity
      8. 7.5.8 Internal Register Structure
    6. 7.6 Register Maps
      1. 7.6.1 Pointer Register (Selects Which Registers Will Be Read From or Written to):
      2. 7.6.2 Temperature Register (Read-Only):
      3. 7.6.3 Configuration Register (Read/Write):
      4. 7.6.4 THYST and TOS Register (Read/Write):
      5. 7.6.5 PRODID: Product ID Register (Read-Only) Pointer Address: 07h
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Simple Fan Controller, Interface Optional
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curve
    3. 8.3 System Examples
      1. 8.3.1 Simple Thermostat, Interface Optional
      2. 8.3.2 Temperature Sensor with Loudmouth Alarm (Barking Watchdog)
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Digital Noise Issues
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Trademarks
    2. 11.2 Electrostatic Discharge Caution
    3. 11.3 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

6 Specifications

6.1 Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted)(1)
MIN MAX UNIT
Supply Voltage Pin (+VS) −0.3 6.5 V
Voltage at A0, A1and A2 Pins −0.3 (+VS + 0.3) and must be ≤ 6.5 V
Voltage at OS, SCL and SDA Pins −0.3 6.5 V
Input Current at any Pin(2) 5 mA
Package Input Current(2) 20 mA
O.S. Output Sink Current 10 mA
O.S. Output Voltage 6.5 V
Storage temperature, Tstg –65 150 °C

6.2 ESD Ratings

VALUE UNIT
V(ESD) Electrostatic discharge Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(1) ±2500 V
Charged-device model (CDM), per JEDEC specification JESD22-C101(2) ±1000
Machine model ±250
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.

6.3 Recommended Operating Conditions(4)(3)

MIN MAX UNIT
Specified Temperature Range (TMIN to TMAX) −55 125 °C
Supply Voltage Range (+VS) LM75A 2.7 5.5 V

6.4 Thermal Information

THERMAL METRIC(1) LM75A UNIT
D DGK
8 PINS 8 PINS
RθJA Junction-to-ambient thermal resistance 200 250 °C/W
(1) For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.

6.5 Temperature-to-Digital Converter Characteristics

Unless otherwise noted, these specifications apply for: +VS = 2.7 to 5.5 Vdc for LM75AIM. TA = TJ = 25°C, unless otherwise noted.
PARAMETER TEST CONDITIONS MIN TYP(9) MAX(5) UNIT
Accuracy TA = −25°C to +100°C
–55°C ≤ TJ ≤ 125°C		 –2 2 °C
TA = −55°C to +125°C
–55°C ≤ TJ ≤ 125°C		 –3 3
Resolution 9 Bits
Temperature Conversion Time See(6) 100 ms
See(6), –55°C ≤ TJ ≤ 125°C 300
Quiescent Current LM75A I2C Inactive 0.28 mA
I2C Inactive, –55°C ≤ TJ ≤ 125°C 0.5
Shutdown Mode, +VS = 3 V 4 μA
Shutdown Mode, +VS = 5 V 6 μA
O.S. Output Saturation Voltage IOUT = 4 mA, –55°C ≤ TJ ≤ 125°C 0.8 V
O.S. Delay See(7), –55°C ≤ TJ ≤ 125°C 1 6 Conversion
TOS Default Temperature See(8) 80 °C
THYST Default Temperature See(8) 75 °C

6.6 Digital DC Characteristics

Unless otherwise noted, these specifications apply for +VS = 2.7 to 5.5 Vdc for LM75AIM and LM75AIMM. TA = TJ = 25°C, unless otherwise noted.
PARAMETER TEST CONDITIONS MIN TYP(9) MAX(5) UNIT
VIN(1) Logical “1” Input Voltage –55°C ≤ TJ ≤ 125°C +VS × 0.7 +VS + 0.3 V
V
VIN(0) Logical “0” Input Voltage –55°C ≤ TJ ≤ 125°C −0.3 +VS × 0.3 V
V
IIN(1) Logical “1” Input Current VIN = +VS 0.005 μA
VIN = +VS, –55°C ≤ TJ ≤ 125°C 1.0
IIN(0) Logical “0” Input Current VIN = 0 V −0.005 μA
VIN = 0 V, –55°C ≤ TJ ≤ 125°C −1.0
CIN All Digital Inputs 5 pF
IOH High Level Output Current
Open drain leakage		 LM75A VOH = 5 V, –55°C ≤ TJ ≤ 125°C 1 μA
VOL Low Level Output Voltage IOL = 3 mA, –55°C ≤ TJ ≤ 125°C 0.4 V
tOF Output Fall Time CL = 400 pF IO = 3 mA, –55°C ≤ TJ ≤ 125°C 250 ns

6.7 I2C Digital Switching Characteristics

Unless otherwise noted, these specifications apply for +VS = 2.7 to 5.5 Vdc for LM75AIM and LM75AIMM on output lines = 80 pF unless otherwise specified. TA = TJ = 25°C, unless otherwise noted.
PARAMETER TEST CONDITIONS MIN TYP(9) MAX(5)(11) UNIT
t1 SCL (Clock) Period –55°C ≤ TJ ≤ 125°C 2.5 ns
t2 Data in Set-Up Time to SCL High –55°C ≤ TJ ≤ 125°C 100 ns
t3 Data Out Stable after SCL Low –55°C ≤ TJ ≤ 125°C 0 ns
t4 SDA Low Set-Up Time to SCL Low (Start Condition) –55°C ≤ TJ ≤ 125°C 100 ns
t5 SDA High Hold Time after SCL High (Stop Condition) –55°C ≤ TJ ≤ 125°C 100 ns
tTIMEOUT SDA Time Low for Reset of Serial Interface(10) LM75A 75 ms
–55°C ≤ TJ ≤ 125°C 325
(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 5mA. The 20mA maximum package input current rating limits the number of pins that can safely exceed the power supplies with an input current of 5mA to four.
(3) Reflow temperature profiles are different for lead-free and non-lead-free packages. Soldering process must comply with Reflow Temperature Profile specifications. Refer to www.ti.com/packaging.(3)
(4) LM75A θJA (thermal resistance, junction-to-ambient) when attached to a printed circuit board with 2 oz. foil similar to the one shown in Thermal Information is summarized in the table below the Operating Ratings table.
(5) Maximum values (limits) are ensured to AOQL (Average Outgoing Quality Level).
(6) The conversion-time specification is provided to indicate how often the temperature data is updated. The LM75A can be accessed at any time and reading the Temperature Register will yield result from the last temperature conversion. When the LM75A is accessed, the conversion that is in process will be interrupted and it will be restarted after the end of the communication. Accessing the LM75A continuously without waiting at least one conversion time between communications will prevent the device from updating the Temperature Register with a new temperature conversion result. Consequently, the LM75A should not be accessed continuously with a wait time of less than 300ms.
(7) O.S. Delay is user programmable up to 6 “over limit” conversions before O.S. is set to minimize false tripping in noisy environments.
(8) Default values set at power up.
(9) Typicals are at TA = 25°C and represent most likely parametric norm.
(10) Holding the SDA line low for a time greater than tTIMEOUT will cause the LM75A to reset SDA to the IDLE state of the serial bus communication (SDA set High).
(11) Timing specifications are tested at the bus input logic levels (Vin(0)=0.3XVA for a falling edge and Vin(1)=0.7XVA for a rising edge) when the SCL and SDA edge rates are similar.
1265804.pngFigure 1. Timing Diagram
1265805.pngFigure 2. Temperature-to-Digital Transfer Function (Non-Linear Scale for Clarity)
1265806.pngFigure 3. Printed Circuit Board Used for Thermal Resistance Specifications
1265810.pngFigure 4. I2C Timing Diagram
1265811.pngFigure 5. I2C Timing Diagrams (Continued)

6.8 Typical Characteristics

1265818.pngFigure 6. Accuracy vs Temperature (LM75A)