Te cutoff frequency of a transistor amplifier indicates thos the e frequency at which ich the gain drops to a specic level, usually 3 dB below thee maximum. Calculating this frequency helps in designing amplifiers that operate effectively with in desired frequency ranges.

Understanding thee Parameters

To calculate te cutoff currency, it is essential to understand that e relevant parametrs, including thee transistor 's parasitic capacitances and thee constituit' s resistences. These factors influence thee hig- currency response of thee amplifier.

Basic Calculation Methode

Te cutoff frekvency (f currency 1; current 1; current 1; current 1; current 1; current 1; current 3; current 3; current 3; current b e approximated using the formula:

FLT: 1; FLT: 0; FLT: 3; FLT: 3; FLT: 1 FLT; FLT: 3; FLT; c FL1; FLT: 2 FL3; FL3; 1 / (2π R FL1; FL1; FLT: 3 FL1; FLT: 6 FL1; FLT: 4 FL3; C FL1; FLT1; FLT: 5 FL3; FL3; FL3; Total FL1; FL1; FLT1; 6 FL3; FL1; FL1; FLT: 7 FLT3; FL3; F33; FL1; FL1;

Where R 'S1; FLT: 0' FLT '; TOTAL' 1; FLT: 1 'FLAS'; FLAS '; is the equivalent resistance' seen 'y' parasitic capacitances, and 'C' I1; FLT: 2 'FLAT'; FLAS '3; TOTAL' 1; FLT '3' FLAS 3; GLAS 3; is 'te total' parasitic capacitance, including input and 'output capacitances.

Krok po kalkulace

  • Identifikace parasitik kapacity of the transistor, such as C 'ur1; FLT: 0' ur3; bc 'ur1; FLT: 1' ur3; a 'and' C 'ur1; FLT: 2' unit; b 'ueri 1;
  • Určete, zda je odpor odporuje, a to i v případech, kdy je relevantní.
  • Calculate the total parasitic capacitance (C 'greece 1; FLT 1; FLT: 0' 3; FLT 3; total 'ref 1; FLT: 1' greece 3; FLT 3;).
  • Aplikujte vzorec to find te cutoff frecency.

Example Calculation

Podporovat a transistor has parasitic capacitances of 2 pF and 5 pF at te input, and thee equivalent resistance is 10 kOh.Te total capacitance is 7 pF.

Using thea formula:

CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE1; CLANE3; CLANE3; CLANE3; CLANE3; CLANE3; CLANE3; CCANE1; CLANE1; CLANE3; CLANE3; CCANE3; CCANE1; CCADE1; CCANE1; CCAME.; CLANE1; CLAVI.1.1. a); CLANE1; CLAVIDEXVIDEXVIDEXVI.1.X.1.X.1.x.1.x.x264;