$${I_C}\, = \,1.3\,mA,\,{R_C}\, = \,2\,k\Omega ,\,{R_E}\, = \,500\,\Omega ,$$
$${V_T}\, = \,26\,mV,\,\beta \, = \,100,\,{V_{CC}}\, = \,15V,$$
$${V_s}\, = \,0.01\,\sin \left( {\omega t} \right)\,V\,and\,{C_b}\, = \,{C_C}\, = \,10\,\mu F.$$
![GATE ECE 2000 Analog Circuits - Bipolar Junction Transistor Question 5 English](https://gateclass.cdn.examgoal.net/examside/questions/4b9f729cab0baa58eed93f2853798c81c2833fe82ac593b81c583ddb5724d3e8.jpg)
(a)What is the small-signal voltage gain, $${A_V} = {V_0}/{V_s}?$$
(b)What is the approximate $${A_{v,}}\,\,if\,\,{C_e}\,\,$$ is removed?
(c)What will $${V_0}\,be\,if\,{C_b}$$ is short circuited?
![GATE ECE 1999 Analog Circuits - Bipolar Junction Transistor Question 6 English](https://gateclass.cdn.examgoal.net/examside/questions/6868855c3de172f1f6a2e1ee5021bcf23d0ee44be233332dc36cc488766877ca.jpg)
Determine the ac small-signal mid-band and voltage gain $$\left( {{V_o}/{V_s}} \right),$$ input resistance (R1, and output resistance (R0) of the circuit. Assume $${V_{T\,\,}} = \,\,26\,mV.$$
![GATE ECE 1998 Analog Circuits - Bipolar Junction Transistor Question 3 English](https://gateclass.cdn.examgoal.net/examside/questions/e84cb3092d904b3047952ac1a5f98f072dfb65d33b445eda0e2308d2d74bb175.jpg)
![GATE ECE 1997 Analog Circuits - Bipolar Junction Transistor Question 8 English](https://gateclass.cdn.examgoal.net/examside/questions/6ae7329eccae768217c1dc25e8967312b540c9fb729bd48839ed2548be81b7d7.jpg)
The N/W components have following values, RC = 2$$k\Omega $$,
RS = $$1.4k\Omega $$,
RE = $$100\Omega $$.
The transistor has specifications, $$\beta \,\, = \,\,100$$
and base spreading resistance $${r_{bb\,}}^1\, = \,100\Omega $$
Evaluate input resistance Ri for two cases. At a frequency of 10 kHz
(a)CE, the bypass capacitor across RE is 25 $$\mu F$$
(b)The bypass capacitor CE is removed leaving RE unbypassed.