SNIS152E May   2009  – July 2015 LM57

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics - Accuracy Characteristics - Trip Point Accuracy
    6. 7.6 Electrical Characteristics - Accuracy Characteristics - VTEMP Analog Temperature Sensor Output Accuracy
    7. 7.7 Electrical Characteristics
    8. 7.8 Switching Characteristics
    9. 7.9 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 LM57 VTEMP Temperature-to-Voltage Transfer Function
        1. 8.3.1.1 LM57 VTEMP Voltage-to-Temperature Equations
      2. 8.3.2 RSENSE
      3. 8.3.3 Resistor Selection
      4. 8.3.4 TOVER and TOVER Digital Outputs
        1. 8.3.4.1 TOVER and TOVER Noise Immunity
      5. 8.3.5 Trip Test Digital Input
      6. 8.3.6 VTEMP Analog Temperature Sensor Output
        1. 8.3.6.1 VTEMP Noise Considerations
        2. 8.3.6.2 VTEMP Capacitive Loads
        3. 8.3.6.3 VTEMP Voltage Shift
    4. 8.4 Device Functional Modes
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 ADC Input Considerations
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Selection of RSENSE Resistors
      3. 9.2.3 Application Curves
      4. 9.2.4 Grounding of the TRIP TEST Pin
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
    3. 11.3 Temperature Considerations
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Community Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

6 Pin Configuration and Functions

TSSOP/PW and WSON/SD/NGR/DFN Packages
8-Pin
Top View
LM57 30080501.gif

Pin Functions

PIN TYPE EQUIVALENT CIRCUIT DESCRIPTION
NAME NO.
GND 1 Ground — Power supply ground
SENSE1 2 — LM57 SNIS188_RSENSE_ESD.gif Trip-point resistor sense. One of two sense pins which selects the temperature at which TOVER and TOVER will assert.
SENSE2 3 — LM57 SNIS188_RSENSE_ESD.gif Trip-point resistor sense. One of two sense pins which selects the temperature at which TOVER and TOVER will assert.
VDD 4 Power Supply voltage
TRIP
TEST		 5 Digital Input LM57 30080538.gif TRIP TEST pin. Active High input.
If TRIP TEST = 0 (default), then the VTEMP output has the analog temperature sensor output voltage.
If TRIP TEST = 1, then TOVER and TOVER outputs are asserted and VTEMP = VTRIP, the temperature trip voltage.
Tie this pin to ground if not used.
TOVER 6 Digital Output LM57 30080521.gif Overtemperature switch output
Active low, open-drain (see LM57 VTEMP Voltage-to-Temperature Equations regarding required pullup resistor.)
Asserted when the measured temperature exceeds the Trip Point Temperature or if TRIP TEST = 1
This pin may be left open if not used.
TOVER 7 Digital Output LM57 30080520.gif Overtemperature switch output
Active high, push-pull
Asserted when the measured temperature exceeds the trip point temperature or if TRIP TEST = 1
This pin may be left open if not used.
VTEMP 8 Analog Output LM57 30080539.gif VTEMP analog voltage output
If TRIP TEST = 0, then VTEMP = VTS, temperature sensor output voltage
If TRIP TEST = 1, then VTEMP = VTRIP, temperature trip voltage
This pin may be left open if not used.
Thermal Pad (WSON package only) — — — Connected to GND