EP-0031

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=Raspberry Pi LM75B Temperature Sensor v1.0 SKU:EP-0031

Product Feature

  • 9bit high resolution ADC in chip
  • Temperature resolution of 0.125°C.
  • I2C bus plug and play
  • Compatible with all kind of development board.

Port

  • Raspberry Pi GPIO pins

Product Parameters

  • Working voltage: 1.8V-5.5V, accuracy can be up to 0.5 when working voltage is higher than 3v.
  • Temperatures range from−55°C to +125°C
  • Supply current of 3.5µA in shutdown mode for power conservation
  • Temperature accuracy of: ±2°C from−25°C to +100°C
  • Temperature accuracy of: ±3°C from−55°C to +125°C

Typical Application

  • Industrial controllers
  • Environmental monitoring
  • Smart home
  • Interactive devices

How to wire it up


How to use it

  • i2c-tools package is required, so you should install it before you get temperature as following command:

sudo apt-get update && sudo apt-get -y install i2c-tools

  • Enable I2c function by editing /boot/config.txt,make sure it contain this two parameter as following:

device_tree=bcm2710-rpi-3-b.dtb
dtparam=i2c_arm=on

    • Or you can use this command to enable I2C:

sudo raspi-config

Lm75.png


    • Select as this picture, then you can enable I2C easily.
Lm752.png


  • Please Remember to reboot your Raspberry Pi.
  • After rebooting, please open a terminal and input this command to get temperature:

i2cget -y 1 0x48 0x00 w |awk '{printf("%0.1f C\n",(a=((("0x"substr($1,5,2)substr($1,3,1))*0.0625)+0.1) )>128?a-256:a)}'

Lm753.png



Examples

  • Shell scripts:
  1. !/bin/bash

while true
do
i2cget -y 1 0x48 0x00 w | awk '{printf("%.1f C.\n", (a=((("0x"substr($1,5,2)substr($1,3,1))*0.0625)+0.1) )>128?a-256:a)}'
sleep 1
done


  • C code: You can login to your Raspberry Pi and open a terminal, and then download the zip package from this link below:

File:LM75 C.tar.gz.zip
unzip it and compile it. unzip LM75_C.tar.gz.zip
tar -xf LM75_C.tar.gz
cd LM75_C/
make
./test.o

Lm75c.png



  • Python running in command line:
  • Python running in X window environment: