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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,

    Itīs 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 donīt 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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