Osservazioni sull’interpretazione basata sulla divisione di corrente

A margine delle analisi e argomentazioni offerte sulle diverse interpretazioni che si possono fare relativamente al comportamento della carica di Gate, è stata fatta una verifica volta a ribadire la consistenza del modello e ad evidenziare la robustezza del metodo.

Il metodo basato sulla divisione della corrente reattiva ha consentito di cambiare profondamente l’approccio con cui si analizza il comportamento della carica di Gate mediante l’introduzione della funzione di divisione. Questa particolarità, oltre ai benefici discussi in precedenza, suggerisce la possibilità di osservare l’evoluzione della corrente di Gate al variare delle tensioni applicate sebbene questa non sia misurata direttamente. Nel fare questo risulterà chiara la solidità della teoria su cui è fondato il metodo.

Partendo dall’analisi sviluppata nel paragrafo 3.6.4, operando alcune manipolazioni dei dati sperimentali è possibile risalire a tre diverse espressioni della corrente di Gate partendo dai diversi contributi misurati:

𝜔𝐼 3-116

𝜔𝐼 3-117

𝜔𝐼 3-118

Il confronto tra gli andamenti delle tre quantità calcolate è riportato in Figura 3-24:

Figura 3-24: Confronto tra gli andamenti della corrente di Gate a piccolo segnale calcolati a partire dalle quantità misurate.

Analizzando i precedenti grafici emerge che, a meno di errori trascurabili derivanti dalla accuratezza dell’estrazione dei singoli elementi e dell’errore di misura, è possibile osservare un ottima sovrapposizione delle curve. Questo consente di dire che il modello è coerente e che l’approccio basato sul criterio della divisione di corrente è effettivamente valido per trattare la carica di Gate su base di un approccio empirico.

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