SNIS119F May   2004  – August 2017 LM60

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

9 Application and Implementation

NOTE

Information in the following applications sections is not part of the TI component specification, and TI does not warrant its accuracy or completeness. TI’s customers are responsible for determining suitability of components for their purposes. Customers should validate and test their design implementation to confirm system functionality.

9.1 Application Information

The device has a low supply current and a wide supply range, therefore it can easily be driven by a battery.

9.1.1 Capacitive Loads

The device handles capacitive loading well. Without any special precautions, the device can drive any capacitive load as shown in Figure 12. Over the specified temperature range the device has a maximum output impedance of 800 Ω. In an extremely noisy environment, adding some filtering to minimize noise pick-up may be required. TI recommends that 0.1 μF be added from +VS to GND to bypass the power supply voltage, as shown in Figure 13. In a noisy environment, adding a capacitor from the output to ground may be required. A 1-μF output capacitor with the 800-Ω output impedance forms a 199-Hz, low-pass filter. Because the thermal time constant of the device is much slower than the 6.3-ms time constant formed by the RC, the overall response time of the device is not be significantly affected. For much larger capacitors, this additional time lag increases the overall response time of the device.

LM60 sva1268115_nis119.gif Figure 12. No Decoupling Required for Capacitive Load
LM60 sva1268116_nis119.png Figure 13. Filter Added for Noisy Environment

9.2 Typical Applications

9.2.1 Full-Range Centigrade Temperature Sensor

Because the LM60 is a simple temperature sensor that provides an analog output, design requirements related to the layout are also important. Refer to Layout for details.

LM60 sva1268102_nis119.png
VO = (6.25 mV/°C × T°C) + 424 mV
Figure 14. Full-Range Centigrade Temperature Sensor (−40°C to +125°C)
Operating From a Single Li-Ion Battery Cell

9.2.1.1 Design Requirements

For this design example, use the design parameters listed in Table 1.

Table 1. Temperature and Typical VO Values of Figure 14

TEMPERATURE (T) TYPICAL VO
125°C 1205 mV
100°C 1049 mV
25°C 580 mV
0°C 424 mV
–25°C 268 mV
–40°C 174 mV

9.2.1.2 Detailed Design Procedure

Selection of the LM60 is based on the output voltage transfer function being able to meet the needs of the rest of the system.

9.2.1.3 Application Curve

LM60 C001_SNIS119.png Figure 15. LM60 Output Transfer Function

9.2.2 Centigrade Thermostat Application

LM60 centigrade_thermostat_Circuit_snis119.gif Figure 16. Centigrade Thermostat

9.2.2.1 Design Requirements

A simple thermostat can be created by using a reference (LM4040) and a comparator (LM7211) as shown in Figure 16.

9.2.2.2 Detailed Design Procedure

Use Equation 2 and Equation 3 to calculate the threshold values for T1 and T2.

Equation 2. LM60 centigrade_thermostat_VT1_EQ_snis119.gif
Equation 3. LM60 centigrade_thermostat_VT2_EQ_snis119.gif

9.2.2.3 Application Curve

LM60 centigrade_thermostat_Curve_snis119.gif Figure 17. Thermostat Output Waveform

9.3 System Examples

9.3.1 Conserving Power Dissipation With Shutdown

The LM60 draws very little power, therefore it can simply be shutdown by driving the LM60 supply pin with the output of a logic gate as shown in Figure 18.

LM60 sva1268119_nis119.png Figure 18. Conserving Power Dissipation With Shutdown