lm3914 ic based on simple battery tester


Posted on Feb 7, 2014

This circuit employs the popular and easy to find LM3914 IC. This kind of IC is quite very simple to drive, requires no voltage regulators (it features a built in voltage regulator) and can be powered from almost every resource. Once the test switch is pushed, the Car battery voltage is supply into a high impedance voltage divider. His function is


lm3914 ic based on simple battery tester
Click here to download the full size of the above Circuit.

to divide 12V to 1, 25V (or lower values to reduced values). This solution is much better than enabling the internal voltage regulator set the 12V sample voltage to be feed into the internal voltage divider simply because it cannot regulate 12V if the voltage falls lower (linear regulators only step down). Simply wiring with no change, the regulator provides secure 1, 25V which can be fed into the precision internal resistor cascade to create sample voltages to the internal comparators. In any case the default establishing let you to determine voltages between 8 and 12V however you can measure even from 0V to 12V setting the offset trimmer to 0 (but i believe that below 9 volt your vehicle would not start). There is a smoothing capacitor (4700uF 16V) it is used to adsorb EMF noises produced from the ignition coil if you`re testing the battery during the engine working. Diesel engines would not need it, but i am not sure. If you want more a level graph rather than a bar graph simply disconnect pin 9 on the IC (MODE) from power. The calculations are usually simple (default).




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    frequency counter
    High-speed-sample-and-hold
    Very Low Frequency VLF Detector Circuit
    DS18B20
    The intellectual digital voltmeter based on MSP430 one-chip computer is designed
    low power simple energy efficient circuit to make single IR LED blink
    MAX2664/MAX2665 VHF UHF Low Noise Amplifiers Circuit
    high capacity dc power relays
    Simple ADS-B Receiver
    GE/MACOM MASTR-III VHF Station
    Vibrato circuit
    Microcontroller circuits
    Light touch variable delay circuit
    A CMOS the spot welding time adjustment circuit b
    TC621 temperature sensor using poultry hatchery electronic thermostat control circuit diagram



    Top