Recent questions tagged bipolar-junction-transistor

The circuit diagram of a standard $\text{TTL NOT}$ gate is shown in the figure. When $V_{i}=2.5 \mathrm{~V},$ the modes of operation of the transistors will be$\mathrm{Q}...

In the following transistor circuit, $V_{B E}=0.7 \mathrm{~V}, r_{e}=25 \; \mathrm{mV} / I_{E},$ and $\beta$ and all the capacitances are very large.The value of DC curre...

In the following transistor circuit, $V_{B E}=0.7 \mathrm{~V}, r_{e}=25 \; \mathrm{mV} / I_{E},$ and $\beta$ and all the capacitances are very large.The mid-band voltage ...

For the amplifier circuit of the figure is the transistor a $\mathrm{B}$ of $800$ . The midband voltage gain $\mathrm{V}^{0} / \mathrm{V}^{1}$, of the circuit will be$0$$...

$\alpha$ - cut off frequency of a bipolar junction transistorincreases with the increase in base widthincreases with the increase in emitter widthincreases with increase ...

In a transistor push-pull amplifierthere is no $d.c.$ present in the outputthere is no distortion in the outputthere are no even harmonics in the outputthere are no odd h...

In the silicon $\text{BJT}$ circuit shown below, assume that the emitter area of transistor $\text{Q1}$ is half that of transistor $\text{Q2.}$The value of current $\text...

The amplifier circuit shown below uses a silicon transistor. The capacitors $\mathrm{C}_{\mathrm{C}}$ and $\mathrm{C}_{\mathrm{E}}$ can be assumed to be short at signal f...

In a uniformly doped $\text{BJT}$, assume that $\text{N}_\text{E}, \text{N}_\text{H}$ and $\text{N}_\text{C}$ are the emitter, base and collector dopings in $\text{atoms/...

Consider the common emitter amplifier shown below with the following circuit parameters: $\beta=100, g_{m}=0.3861 \mathrm{~A / V}, \mathrm{r}_{\mathrm{o}}=\infty, \mathrm...

In a transistor having finite $B$, the forward bias across the base emitter junction is kept constant and the reverse bias across the collector-base junction is increased...

If the transistors in the given figure have high values of $\beta$ and a $V_{B E}$ of $0.65$ volt, the current $I$, flowing through the $2$ kilo ohms resistance will be $...

Discrete transistors $T_1$ and $T_2$ having maximum collector current rating of $0.75$ amps are connected in parallel as shown in the figure. This combination is treated ...

In figure, all transistors are identical and have a high value of beta. The voltage $V_{D C}$ is equal to_________.

For the $\text{BJT Q}_1$ in the circuit shown below, $\beta=\infty, \mathrm{V}_{\mathrm{BEon}}=0.7 \mathrm{V}, \mathrm{V}_{\mathrm{CEsat}}=0.7 \mathrm{V}$. The switch is ...

For a $\mathrm{BJT}$, the common-base current gain $\alpha=0.98$ and the collector base junction reverse bias saturation current $\mathrm{I}_{\mathrm{CO}}=0.6 \;\; \mu \m...

The base of an $\text{npn BJT T1}$ has a linear doping profile $N_{B}\left ( x \right )$ as shown below. The base of another $\text{npn BJT T2}$ has a uniform doping $N_...

For the $\text{BJT}$ in the amplifier shown below, $V_{BE}=0.7V,\:kT/q=26\:mV$. Assume that $\text{BJT}$ output resistance $(r_{o})$ is very high and the base current is ...

In the voltage regulator shown below, $V_{1}$ is the unregulated imput at $15\:V$. Assume $V_{BE}=0.7\:V$ and the base current is negligible for both the $\text{BJTs}$. I...

The injected excess electron concentration profile in the base region of an $npn$ BJT, biased in the active region, is linear, as shown in the figure. If the area of the ...

The Ebers-Moll model of a $BJT$ is valid only in active modeonly in active and saturation modesonly in active and cut-off modesin active, saturation and cut-off modes

In the circuit shown in the figure, the BJT has a current gain $(\beta)$ of $50.$ For an emitter-base voltage ܸ $V_{EB} = 600\: mV,$ the emitter-collector voltage $V_{EC}...

An npn BJT having reverse saturation current $I_{S} = 10^{-15}\:A$ is biased in the forward active region with $V_{BE} = 700\: mV.$ The thermal voltage $(V_{T})$ is $25\:...

In the ac equivalent circuit shown, the two BJTs are biased in active region and have identical parameters with $\beta \gg 1$. The open circuit small signal voltage gain ...

Consider two BJTs biased at the same collector current with area $A_1=0.2 \mu m \times 0.2 \mu m$ and $A_2 = 300 \mu m \times 300 \mu m$. Assuming that all other device p...

In the circuit shown, the silicon BJT has $\beta = 50$. Assume $V_{BE}= 0.7 \: V$ and $V_{CE(sat)}= 0.2 \: V$. Which one of the following statements is correct? ...

An increase in the base recombination of a BJT will increasethe common emitter dc current gain $\beta$the breakdown voltage $BV_{CEO}$the unity-gain cut-off frequency $f_...

A BJT is biased in forward active mode. Assume $V_{EE} = 0.7\:V, \: kT/q = 25\:mV$ and reverse saturation current $I_{S} = 10^{-13}\:A.$ The transconductance of the BJT ...

In the voltage regulator circuit shown in the figure, the op-amp is ideal. The BJT has $V_{BE} = 0.7\:V$ and $\beta = 100,$ and the zener voltage is $4.7\:V.$ For a regul...

In the circuit shown, transistors $Q_1$ and $Q_2$ are biased at a collector current of $2.6$ $mA$. Assuming that transistor current gains are sufficiently large to assume...