Regolatore 78L05 tensione out bassa

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ciao tutti,
stavo controllando un arduino standalone che ho fatto qualche tempo fa ed ho notato una cosa:
il regolatore onboard 78l05 http://users.ece.utexas.edu/~valvano/datasheets/lm78l05.pdf non regola bene la tensione, dati 8.71 volt di ingresso da una batteria ricaricabile da 9 volt in uscita ottengo solamente 3.96 volt invece dei 5 volt che dovrebbe erogare...
sul pin di uscita del regolatore c'è un condensatore da 10uf, niente condensatori in ingresso (il filo tra il circuito e la batteria è 20 cm in tutto ).
ho fatto una prova anche senza atmega328p e la tensione misurata è 4.34 volt, leggermente superiore ma sempre molto insoddisfacente..
dal datasheet: min output voltage 4.75 volt
il regolatore è una "sola"?

il regolatore non è una ciofeca, però fornisce max 100 ma. forse il tuo circuito ne assorbe di più?
hai provato sostituirlo con un altro regolatore?

forse il c in uscita è troppo grosso, e potrebbe dargli noia anche l'assenza del c in ingresso. io ne metterei uno da 1 uf in ingresso ed uno da 0.1uf in uscita.


Arduino Forum > International > Italiano > Generale (Moderator: leo72) > Regolatore 78L05 tensione out bassa


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