temperature sensor-LM35...

Discussion in 'The Projects Forum' started by darkmaster8905, May 11, 2010.

  1. darkmaster8905

    Thread Starter New Member

    May 11, 2010
    hello... can u help me to give some idea about the simple temperature sensor that i used LM35 and the output i used LCD and LED.... LCD show the value of the temperature and the LED show the level of the temperature such as green in the normal condition.... i used AT89c51 as my microcontroller... from the micrcontroller i already used some of pin to create another sensor.. i have another 8pins as part of temperature sensor... if i directly used the LED and not use the LCD i need 11pins that means i need another 3pins... can u suggest any idea for me or another method to create the simple temprature.. really hope from u all... thanks for helping...

    component i used:-
    AT89c51 (40 pins)-already used 32pins ot another sensor
    LED-red,yellow and green
  2. SgtWookie


    Jul 17, 2007
    Why don't you look at using a 1-wire or 2-wire LCD interface?

    It involves using a 74HC174 or 74HC595 shift register, some caps/resistors, and some "bit-twiddling" to clock your LCD bytes out a bit at a time.

    Roman Black's 1-wire is here:

    Myke Predko's 2-wire is here:

    Both for PICs, but you can write code to use the idea.
    darkmaster8905 likes this.
  3. tracecom

    AAC Fanatic!

    Apr 16, 2010
    You can use an LM3914 to interface directly from the LM35 to colored LED's. See the LM3914 datasheet for a schematic.