Problem Statement

$1.$ Find the component values of a single$-$stage audio amplifier using a Bipolar Junction Transistor $($BJT$)$ for an audio application. You must fulfill as much of the following requirements as possible.

$-$ Open circuit voltage gain should be $5$ times sum of all digits in your registration number e$.$g$.$ your registration number is $\backslash (23\backslash$mathrm$\{$~L$\}-1234\backslash )$ then voltage gain would be $\backslash (5(1+2+3+4)=50\backslash )$

$-$ Input resistance must be greater than $\backslash (40\backslash$mathrm$\{$k$\}\backslash$Omega $\backslash )$

$-$ The output impedance should be less than $\backslash (500\backslash$Omega $\backslash )$

$-$ The circuit is powered by a $+15$ V DC supply.

$-$ Consider a biasing scheme that provides the thermal bias stability.

$-$ As a starting point take DC operating current $\backslash ($ I$\_\{$C$\}=1\backslash$mathrm$\{$~mA$\}\backslash )$ at room temperature.

$-$ Assume $\backslash (\backslash$beta$=100\backslash )$

$-$ Take $\backslash ($ I$\_\{$s$\}=10^\{-14\}\backslash$mathrm$\{$~A$\}\backslash )$ and $\backslash ($ V$\_\{$B E$\}=0\mathrm{.}7\backslash$mathrm$\{$~V$\}\backslash )$ at room temperature

$2.$ Select the standard available resistor values with $5\backslash \%$ tolerance and Analyze your circuit. Find the input resistance, output resistance, open circuit voltage gain and signal swing to check if it fulfills the requirement.

$3.$ Analyze how variations in temperature from $\backslash (-10^\{\backslash$circ$\}\backslash$mathrm$\{$C$\}\backslash )$ to $\backslash (60^\{\backslash$circ$\}\backslash$mathrm$\{$C$\}\backslash )$ affects the performance of the amplifier.

Objectives: To help students understand the concepts related to the design and analysis of single stage BJT amplifier.

Deliverables: A complete report that should include the following

$-$ Schematic diagram

$-$ Detailed Calculations showing how each component value was chosen

$-$ In depth analysis of your design. It should include the explanation about the conflicting requirements and tradeoffs. Show which one of them are met in your design.

$-$ Temperature analysis: Clearly explain, with calculations, how changes in temperature affect the dc and ac parameters.

$-$ Simulation Results $($Bonus$)$: Verify gain, input resistance, and output swing using a circuit simulation tool of your choice.