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  1. #1
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    L7805CV giving 5.4Volts

    I am using L7805CV from STmicroelectronics purchased from local market.
    I have been using this regulator for a very long time. I always check the voltage and it is always around 4.92 to 4.97. But this time the regulator is giving 5.4V.
    I am attaching my circuit diagram.

    Any help would save my day.
    Thank in advanceClick image for larger version. 

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  2. #2
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    Re: L7805CV giving 5.4Volts

    Hi,

    It´s urgent to read datasheet in detail:

    It says:
    Note: Minimum load current for regulation is 5 mA.
    --> Measure output voltage with minimum load of at least 5mA. If the voltage still is above specified voltage, then replace the regulator.

    Klaus
    Please don´t contact me via PM, because there is no time to respond to them. No friend requests. Thank you.



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  3. #3
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    Re: L7805CV giving 5.4Volts

    Klauss is right.
    In addition, make sure your ground points are all properly connected - especially regulator pin 3



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  4. #4
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    Re: L7805CV giving 5.4Volts

    I have never seen a "local market". Does it sell cheap fake or defective parts like ebay does?



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