SNIS197 August   2017 LM60-Q1

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
    6. 7.6 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 LM60 Transfer Function
    4. 8.4 Device Functional Modes
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Capacitive Loads
    2. 9.2 Typical Applications
      1. 9.2.1 Full-Range Centigrade Temperature Sensor
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curve
      2. 9.2.2 Centigrade Thermostat Application
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
        3. 9.2.2.3 Application Curve
    3. 9.3 System Examples
      1. 9.3.1 Conserving Power Dissipation With Shutdown
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
    3. 11.3 Thermal Considerations
  12. 12Device and Documentation Support
    1. 12.1 Receiving Notification of Documentation Updates
    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

8 Detailed Description

8.1 Overview

TheLM60-Q1 devices are precision analog bipolar temperature sensors that can sense a −40°C to +125°C temperature range while operating from a single 2.7-V supply. The output voltage of the LM60-Q1 is linearly proportional to Celsius (Centigrade) temperature (6.25 mV/°C) and has a DC offset of 424 mV. The offset allows reading negative temperatures with a single positive supply. The nominal output voltage of the device ranges from 174 mV to 1205 mV for a −40°C to +125°C temperature range. The device is calibrated to provide accuracies of ±2.0°C at room temperature and ±3°C over the full −25°C to +125°C temperature range.

With a quiescent current of the device is less than 110 μA, self-heating is limited to a very low 0.1°C in still air in the SOT-23 package. Shutdown capability for the device is intrinsic because its inherent low power consumption allows it to be powered directly from the output of many logic gates.

The output of the LM60-Q1 is a Class A base emitter follower, thus the LM60-Q1 can source quite a bit of current while sinking less than 1 µA. In any event load current should be minimized in order to limit it's contribution to the total temperature error. The temperature-sensing element is based on a delta VBE topology of two transistors (Q1 and Q2 in Functional Block Diagram) that are sized with a 10:1 area ratio.

8.2 Functional Block Diagram

LM60-Q1 sva1268117_nis119.gif

8.3 Feature Description

8.3.1 LM60 Transfer Function

The LM60 follows a simple linear transfer function to achieve the accuracy as listed in Electrical Characteristics as given:

Equation 1. VO = (6.25 mV/°C × T °C) + 424 mV

where

  • T is the temperature
  • VO is the LM60-Q1 output voltage

8.4 Device Functional Modes

The only functional mode for this device is an analog output directly proportional to temperature.