Gavin Jackson wrote:
>
> Hi there once again
>
> Correct me if I'm wrong, but I though that the 78XX voltage
> regulators can only take 3X the output voltage on their input,
> so the maximum supply that a 7805 can have as its input
> is 15V.
>
> Let me know
>
> Gavin

Sorry to correct you, but the LM78xx-series are spec'd as follows :
all 78xx devices execpt 7824 : max input voltage 35 V DC
7824 : max input voltage : 40 V DC

with regards,  Reelf

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