Transcription of Analog & Digital Electronics
{{id}} {{{paragraph}}}
Example: bachelor of science
Analog & Digital Electronics
Analog & Digital ElectronicsCourse No: PH-218 Lec-12: frequency Response of BJT AmplifiersCourse Instructors: Dr. A. P. VAJPEYID epartment of Physics, Indian Institute of Technology Guwahati, India1 High frequency Response of CE Amplifier Athighfrequencies,internaltransistor junction capacitances docome into play, reducing an amplifier'sgain and introducing phase shift asthe signal frequency BJT, Cbeis the B-E junction capacitance, and Cbcis the B-C junction capacitance. (output to input capacitance)(output to input capacitance) At lower frequencies, the internal capacitances have a veryhighreactance because of their low capacitance value (usually only a few pf)and the low frequency value. Therefore, they look like opensand haveno effect on the transistor's performance. As the frequency goes up, the internal capacitive reactance's godown, and at some point they begin to have a significanteffect on the transistor's gain. When the reactance of Cbebecomes small enough, a significant amount of the signal voltage is lost due to a voltage-divider effect of the source resistance and the reactance of frequency Response of CE Amplifier 3 When the reactance of Cbcbecomessmallenough,asignificant amount of outputsignal voltage is fed back out ofphase with the input (negativefeedback),thuseffectivelyreduci ng the voltage Miller effect occurs only in inverting amplifiers it is the invert
When the reactance of C be becomes small enough, a significant amount of the signal voltage is lost due to a voltage-divider effect of the source resistance and the reactance of C be. High frequency …
Loading..
Tags:
Information
Domain:
Source:
Link to this page:
Please notify us if you found a problem with this document: