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1Instructables1,743Views8CommentsJoined December 28th, 2013
Hi, This is ArunS,hobbiyst of Electronics,Aeronautics,Automation.

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  • arunscuddalore commented on arunscuddalore's instructable BATTERY LOW ALARM5 days ago
    BATTERY LOW ALARM

    Hi,As per calculation, the standby current for the above circuit is less than 2mA.

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  • arunscuddalore commented on arunscuddalore's instructable BATTERY LOW ALARM1 week ago
    BATTERY LOW ALARM

    Hi,The Schematic and PCB presented here is Revised /updated one.You can use the PCB to make your project.

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  • arunscuddalore commented on arunscuddalore's instructable BATTERY LOW ALARM2 weeks ago
    BATTERY LOW ALARM

    Thank you for your comment

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  • arunscuddalore commented on arunscuddalore's instructable BATTERY LOW ALARM2 weeks ago
    BATTERY LOW ALARM

    Hi, Now almost everything is rectified . Go through the entire project.Regards,ArunS

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  • arunscuddalore made the instructable BATTERY LOW ALARM3 weeks ago
    BATTERY LOW ALARM

    Dear Friend, Thanks for explaining more theoretically. After careful examination of my circuit ,two components were wrongly typed.1) D3 is 1N5234 (wrongly typed as 1N4148). Since 1N5234 is a 6.2 volt Zener Diode,which has to be placed in reverse biased condition.So, no need to change the circuit. 2) R3 is 10Kilo ohm( wrongly typed as10k/100k)To get an alarm , Q1 needs a positive signal on its base from pin 1 (of the LM358).For that, pin 1 to get positive (enough), pin 3 (+ in) needs to have a higher voltage than pin 2 (- in).This condition is TRUE , if we are using LM358 in NON INVERTING COMPARATOR circuit. In this type when Vin is greater than Vref, output will be postive.According to your statement swapping pins 2 and 3 i.e Vref to pin 3 and Vin to pin 2 will not work properly and l...

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    Dear Friend, Thanks for explaining more theoretically. After careful examination of my circuit ,two components were wrongly typed.1) D3 is 1N5234 (wrongly typed as 1N4148). Since 1N5234 is a 6.2 volt Zener Diode,which has to be placed in reverse biased condition.So, no need to change the circuit. 2) R3 is 10Kilo ohm( wrongly typed as10k/100k)To get an alarm , Q1 needs a positive signal on its base from pin 1 (of the LM358).For that, pin 1 to get positive (enough), pin 3 (+ in) needs to have a higher voltage than pin 2 (- in).This condition is TRUE , if we are using LM358 in NON INVERTING COMPARATOR circuit. In this type when Vin is greater than Vref, output will be postive.According to your statement swapping pins 2 and 3 i.e Vref to pin 3 and Vin to pin 2 will not work properly and leads to a reverse effect or reverse alarm.But I have designed the circuit in which , LM358 is used in INVERTING COMPARATOR. In this type when Vin is less than Vref, output will be postive.Here Vref is taken from R1 and D3 voltage divider junction and it is fed to non inverting pin(no.3/+).Vin is taken from variable resistor R3 junction and it is fed to inverting pin(no.2/-) and accordingly schematic and PCB will be updated soon.A picture enclosed here will be explaining more theoretically and the values were verified practically.As per the datasheet of IC, it is not mandatory to tie second op-amp inputs to gnd, if we are not using the second op-amp. Thanks for making me in depth analysis of the circuit.

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  • arunscuddalore followed arunscuddalore3 weeks ago
      • BATTERY LOW ALARM
  • arunscuddalore commented on arunscuddalore's instructable BATTERY LOW ALARM3 weeks ago
    BATTERY LOW ALARM

    Thanks for your comment. Have you done prototype of this circuit or you verified with any simulation software.Anyhow once again i will verify both schematic and PCB

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  • arunscuddalore commented on arunscuddalore's instructable BATTERY LOW ALARM3 weeks ago
    BATTERY LOW ALARM

    It is better idea. But micro soldering station is costlier when compared to ordinary 35 watt soldering iron.Moreover skill is required for soldering SMD components, which is somewhat difficult to ordinary people.

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