You have received the design for a single transistor amplifier shown below from a colleague. Data sheets indicate the transistor has the following parameters under the pertinent operating conditions:
1. Draw the DC equivalent circuit for the amplifier and use it to determine the DC bias point of the transistor by manual analysis. Provide a clear record of your working and state VBE, IC and VCE for the transistor.
2. Draw the AC equivalent circuit for the amplifier and use it to determine the performance parameters for the amplifier by manual analysis. Provide a clear record of your working and state: the resultant mid-band small signal gain in dB, the amplifier’s mid-band input and output impedance, the low-frequency turning point of the amplifier in Hz assuming that the input capacitor is dominant.
3. Enter the amplifier design into a circuit simulator such as Multisim. Conduct a DC operating point analysis to confirm the bias conditions of the transistor and an AC analysis to confirm the gain and low frequency turning point. Your submission should include a schematic for the circuit simulated and clear explanation of how the numerical results quoted have been derived. Where appropriate include simulator output graphics with annotations to indicate relevant results. Comment on how well or otherwise the simulated results match those calculated and what might be the reason for any discrepancies observed.
Vo = 0.75 V, hFE = hfe = 400, hie = 1800Ω, hoe = 37.5mS
1. Draw the DC equivalent circuit for the amplifier and use it to determine the DC bias point of the transistor by manual analysis. Provide a clear record of your working and state VBE, IC and VCE for the transistor.
2. Draw the AC equivalent circuit for the amplifier and use it to determine the performance parameters for the amplifier by manual analysis. Provide a clear record of your working and state: the resultant mid-band small signal gain in dB, the amplifier’s mid-band input and output impedance, the low-frequency turning point of the amplifier in Hz assuming that the input capacitor is dominant.
3. Enter the amplifier design into a circuit simulator such as Multisim. Conduct a DC operating point analysis to confirm the bias conditions of the transistor and an AC analysis to confirm the gain and low frequency turning point. Your submission should include a schematic for the circuit simulated and clear explanation of how the numerical results quoted have been derived. Where appropriate include simulator output graphics with annotations to indicate relevant results. Comment on how well or otherwise the simulated results match those calculated and what might be the reason for any discrepancies observed.
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