BJT Amplifiers

The Miller effect in the context of a Common Emitter amplifier explains

Which one of the following statements is correct about an ac-coupled common- emitter amplifier operating in the mid-band region?

A BJT is baised in forward active mode Assume V BE = 0.7 V, kT/q = 25 mV and reverse saturation current I s = 10 -13 A. The transconductance of the BJT (in mA/V) is

If the emitter resistance in a common-emitter voltage amplifier is not bypassed, it will

A BJT in common-base configuration is used to amplify a signal received by a $$50\,\Omega $$ antena. Assume kT/q = 25 mV. The value of the collector bias current ( in mA ) required to match the input impedance of the amp...

The cascode amplifier is a multistage configuration of

A bipolar transistor is operating in the active region with a collector current of 1mA. Assuming that the 'β' of the transistor is 100 and the transconductance (g m ) and the input resistance ($${r_\pi }$$) of the transi...

Generally, the gain of a transistor Amplifier falls at high frequency due to the

Three identical amplifiers with each one having a voltage gain of 50, input Resistance of 1 KΩ and output resistance of 250Ω, are cascaded. The open circuit voltage gain of the combined Amplifier is

An npn BJT has g m = 38 mA/V, $${C_\mu }\, = {10^{ - 14}}$$ F, $${C_\pi }\, = 4\, \times {10^{ - 13}}\,F$$ and DC current gain $$\beta \, = \,90$$. For this transistor f T and $${f_\beta }$$ are

The current gain of a bipolar transistor drops at high frequencies because of

An amplifier is assumed to have a single pole high frequency transfer function. The rise time of its output response to a step function input is 35 nsec. The upper 3 dB frequency (in MHz) for the amplifier to a sinusoida...

An NPN transistor (with $${C_\pi }\,\, = \,\,0.3\,\,$$ pf) has a unity gain cutoff frequency $${f_T}$$ of 400 MHz at a DC-bias current I c = 1mA. The value of its $${C_\mu }$$ (in pf) is approximately $$\left( {{V_T}\, =...

In a differential Amplifier, CMRR can be improved by using an increased

From a measurement of the rise time of the output pulse of an amplifier whose input is a small amplitude square wave, one can estimate the following parameter of the amplifier:

The $${f_T}$$ of a BJT is related to its $${g_{m,}}\,\,{C_\pi }$$ and $${C_\mu }$$ as follows

The emitter coupled pair of BJT’s gives a linear transfer relation between the differential output voltage and the differential input voltage V id only. When the magnitude of V id is less than '$$\alpha$$' times the ther...

Match the following. Group - I (a)Cascode amplifier (b)Differential Amplifier (c)Darlington pair common-collector Amplifier Group - II (1)does not provide current gain (2)is a wide band Amplifier (3)has very low input im...

An npn transistor has a beta cut-off frequency $${f_\beta }$$ of 1MHz and Common Emitter short circuit low frequency current gain $${\beta _o}$$ of 200. The unity gain frequency $${f_T}$$ and the alpha cut-off frequency...

A change in the value of the Emitter resistance (R e in a difference Amplifier.

An RC-Coupled Amplifier is assumed to have a single-pole low frequency transfer function. The maximum lower-cutoff frequency allowed for the Amplifier to pass 50 Hz square wave with no more than 10% tilt is ______.

In order to reduce the harmonic distortion in an amplifier, its dynamic range has to be _________

A common emitter transistor amplifier has a collector current of 1.0 mA when its base current is 25 $$\mu$$A at the room temperature. It's input resistance is approximately equal to (in K$$\Omega$$) _________ .

In a multi-stage RC-Coupled Amplifier the coupling capacitor.

The bandwidth of an n-stage tuned amplifier, with each stage having a band width of B, is given by

Which of the following statements are correct for basic transistor Amplifier configurations?

The quiescent collector current I c , of a transistor is increased by changing resistance. As a result