National Semiconductor LM32, LM40, LM41 User Manual

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Revision B

November 9, 2004

LM32, LM40, LM41 Evaluation Board User’s Guide

LM32

,

LM40

,

LM41 Evaluation Board User’s Guide

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LM32, LM40, LM41 Evaluation Board User’s Guide

Table of Contents

Table of Contents 2 References 3

1.0 Introduction 4

1.1 Block Diagram 4

2.0 Quick Start 5

2.1 Quick Start Diagram 5

2.2 LM32 Quick Start 6

2.3 LM40 Quick Start 8

2.4 LM41 Quick Start 10

3.0 Functional Description 12

3.1 Evaluation Board Connection Tables 12

3.1.1 LM32 Evaluation Board Connection Table 12

3.1.2 LM40 Evaluation Board Connections Table 13

3.1.3 LM41 Evaluation Board Connections Table 14

4.0 Software Installation and Operation 15

5.0 Electrical and Mechanical Specifications 16

5.1 Electrical Specifications 16

5.2 Electrical Schematic 16,17

5.3 Evaluation Board Layout 18

5.4 Bill of Materials 19

5.5 Mechanical Specifications 20

5.5.1 Operating Mechanical and Environmental Specifications 20

5.5.2 Evaluation Board Mechanical Dimensions 20

5.5.3 Electrostatic Discharge (ESD) Precautions 20

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LM32, LM40, LM41 Evaluation Board User’s Guide

References

1. Datasheet for the device on the evaluation board: a. “LM32 Dual Thermal Diode Temperature Sensor With SensorPath™ Bus” or b. “LM40 Hardware Monitor with Dual Thermal Diodes and SensorPath™ Bus” or

c. “LM41 Hardware Monitor with Thermal Diode Inputs and SensorPath™ Bus”

The latest copy of the LM32, LM40, LM41 datasheets can be obtained by going to the National Semiconductor website www.national.com, by searching on “LM32”, “LM40”, or “LM41”, and then downloading the appropriate datasheet file.

2. SensorEval, Version 1.04b or later, Evaluation Board CD containing: a. The SensorEval.exe executable program used to run the LM32, LM40, or LM41

Evaluation Boards. b. A softcopy of this User’s Guide c. A readme.txt file with useful information about the program. d. A softcopy of the SensorEval Software manual.

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1.0 Introduction

The LM32/LM40/LM41 Evaluation Board is used together with the National Semiconductor SensorEval software (provided in the kit), and with a USB cable (not provided in the kit), and with an external personal computer (PC). Power to the LM32/LM40/LM41 Evaluation Board is provide by the +5VDC line of the USB connection. No external power supply or signal sources are required for operation of the LM32/LM40/LM41 evaluation board.

Before connecting the PC to the LM32/LM40/LM41 evaluation board through the USB cable, the PC is first turned on and allowed to go through its boot-up procedure. The user installs and initiates the SensorEval software. See Section 4.0 for software installation details.

After the SensorEval software is running, the user can connect the USB cable first to the computer and then to the LM32/LM40/LM41 Evaluation Board.

The PC should be able to recognize the board and the user simply runs the SensorEval software and selects the LM32/LM40/LM41 Eval Board radio button. The software allows the

user to select which of the LM32, LM40, or LM41 devices is used.

The block diagram below describes the LM32/LM40/LM41 Evaluation Board itself. The USB input provides the +5.0 VDC power to the board, which is regulated down to 3.3 VDC to power the IC’s. The EEPROM is programmed at the factory with a unique ID code for this particular board. When the USB cable is plugged in, the PC interrogates the USB devices and can identify this device as the LM32/LM40/LM41 Evaluation Board.

The microcontroller on the board provides the single wire signal (SWD), provides the address (ADD) select signal, and relays the information from the LM32, LM40, or LM41 to the PC via the USB lines.

The pins available to the user for probing vary according to device type. The output pinouts for each of the LM32, LM40, or LM41 are shown in the Connections sections and the Electrical Schematic.

1.1 Block Diagram

USB

Input

EEPROM

Circuit

Voltage

Regulator

Circuit

Microcontroller

Circuitry

USB D+ USB D-

SCL SDA

U5

LM32, LM40,

or LM41

+5.0 VDC

GND

+3.3 VDC

+3.3V

SWD

ADD

GND

SWD ADD

D1+

D1D2+

D2-

Other Signals

depending on device.

(See Connections and

Schematic)

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2.0 Quick Start

1. Install the CD into the CD drive of the computer and install the SensorEval software (see Section

4.0).

2. Hookup the USB cable between the PC or notebook computer and the LM32/LM40/LM41 Evaluation

Board as shown in Quick Start Diagram below.

2.1 Quick Start Diagram

Important! NO EXTERNAL POWER SUPPLY OR SIGNAL INPUTS ARE REQUIRED!

For

Socket

(not used)

LM32/40/41 Evaluation Board

National Semiconductor

Q1

LM41

LM40

LM32

LM40

LM41

U4

J3

J2

J6

Q2

See

Connection

Diagrams

See

Connection

Diagrams

LM32/40/41

PC with

SensorEval

software installed

USB Cable

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2.2 LM32 Quick Start

1. Run the SensorEval software by clicking the icon on the desktop.

2. The first screen will look like this:

Select the LM32 Evaluation Board. Click OK.

3. The next screen will look like this:

Select “Read Cont” box to read the temperature continuously. Notice that there are three tabs for the registers “00 through 05”, “08 through 09”, and “09 through 20”. The first screen (above) displays the registers 00hex through 05hex.

For Register 05, “Device Func1 Enable”,

select ENABLED.

4. Click on the 09-20 Register Tab. The Screen should look like this:

For Register 0A select Enable for Temp Sensor 0, 1 and 2.Note that Temp2 (Remote sensor [Q1 on the board] 2 is displayed in the box on the right and is updated as the temperature of the Q1 changes.

5. Click on the 08-09 Register Tab. The screen should look like this:

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National Semiconductor LM32, LM40, LM41 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual