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5.7: Exercises

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    34245
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    Unless otherwise specified, use \(\beta\) = 100.

    5.7.1: Analysis Problems

    1. Plot the load line for the circuit of Figure \(\PageIndex{1}\). \(V_{CC}\) = 20 V, \(V_{EE}\) = −8 V, \(R_B\) = 7.5 k\(\Omega\), \(R_E\) = 10 k\(\Omega\), \(R_C\) = 12 k\(\Omega\).

    clipboard_e7772f8144febab510d3cc2767c45d6b5.png

    Figure \(\PageIndex{1}\)

    2. Determine the new Q point for Problem 1 if \(\beta\) = 250.

    3. Plot the load line for the circuit of Figure \(\PageIndex{2}\). \(V_{EE}\) = 5 V, \(V_{CC}\) = −18 V, \(R_B\) = 22 k\(\Omega\), \(R_E\) = 1.2 k\(\Omega\), \(R_C\) = 1.5 k\(\Omega\).

    clipboard_ecfbb1416638e6f4ce5826ac266ddd749.png

    Figure \(\PageIndex{2}\)

    4. Determine the new Q point for Problem 3 if \(\beta\) = 50.

    5. Plot the load line for the circuit of Figure \(\PageIndex{3}\). \(V_{CC}\) = 20 V, \(R_1\) = 15 k\(\Omega\), \(R_2\) = 5 k\(\Omega\), \(R_E\) = 4.3 k\(\Omega\), \(R_C\) = 9.1 k\(\Omega\).

    clipboard_e280dfcb1219dac32b1d25d3d25d437e8.png

    Figure \(\PageIndex{3}\)

    6. Determine the new Q point for Problem 5 if \(\beta\) = 150.

    7. Plot the load line for the circuit of Figure \(\PageIndex{4}\). \(V_{EE}\) = 16 V, \(R_1\) = 12 k\(\Omega\), \(R_2\) = 4.7 k\(\Omega\), \(R_E\) = 6.2 k\(\Omega\), \(R_C\) = 10 k\(\Omega\).

    clipboard_e3cc27f2dd5528c692ebcb892b04a1d5c.png

    Figure \(\PageIndex{4}\)

    8. Determine the new Q point for Problem 7 if \(\beta\) = 200.

    9. Plot the load line for the circuit of Figure \(\PageIndex{5}\). \(V_{CC}\) = 12 V, \(R_B\) = 560 k\(\Omega\), \(R_C\) = 3.3 k\(\Omega\).

    clipboard_e0eb1fd2cfb9efec91abe56580bf5b30e.png

    Figure \(\PageIndex{5}\)

    10. Determine the new Q point for Problem 9 if \(\beta\) = 75.

    11. Plot the load line for the circuit of Figure \(\PageIndex{6}\).

    clipboard_e05468077fa2f3a31c99368fdc379784b.png

    Figure \(\PageIndex{6}\)

    12. Determine the new Q point for Problem 11 if \(\beta\) = 200.

    13. Plot the load line for the circuit of Figure \(\PageIndex{7}\). \(V_{CC}\) = 15 V, \(R_B\) = 470 k\(\Omega\), \(R_E\) = 560 \(\Omega\), \(R_C\) = 3.3 k\(\Omega\).

    clipboard_e9242a6b146ae4636fb462bf997e1fb7e.png

    Figure \(\PageIndex{7}\)

    14. Determine the new Q point for Problem 13 if \(\beta\) = 170.

    15. Plot the load line for the circuit of Figure \(\PageIndex{8}\).

    16. Determine the new Q point for Problem 15 if \(\beta\) = 75.

    17. Plot the load line for the circuit of Figure \(\PageIndex{9}\). \(V_{EE}\) = 18 V, \(R_B\) = 680 k\(\Omega\), \(R_E\) = 270 \(\Omega\), \(R_C\) = 3.9 k\(\Omega\).

    18. Determine the new Q point for Problem 17 if \(\beta\) = 200.

    clipboard_e73642d702055c63234216f19c56a6e3a.png

    Figure \(\PageIndex{8}\)

    clipboard_eab4aff8079571495f39bf0acc53f829a.png

    Figure \(\PageIndex{9}\)

    5.7.2: Design Problems

    19. Determine a value for \(R_E\) in the circuit of Figure \(\PageIndex{1}\) to set \(I_C\) = 2 mA. Use \(V_{CC}\) = 20 V, \(V_{EE}\) = −8 V, \(R_B\) = 10 k\(\Omega\), \(R_C\) = 5.6 k\(\Omega\).

    20. Determine a value for \(R_C\) in the circuit of Figure \(\PageIndex{2}\) to set \(V_{CE}\) = 10 V. Use \(V_{CC}\) = −25 V, \(V_{EE}\) = 6 V, \(R_B\) = 15 k\(\Omega\), \(R_E\) = 6.8 k\(\Omega\).

    21. Determine a value for \(R_C\) in the circuit of Figure \(\PageIndex{3}\) to set \(V_{CE}\) = 8 V. Use \(V_{CC}\) = 24 V, \(R_1\) = 22 k\(\Omega\), \(R_2\) = 10 k\(\Omega\), \(R_E\) = 5.6 k\(\Omega\).

    22. Determine new values for \(R_1\) and \(R_2\) in the circuit of Figure \(\PageIndex{4}\) in order to set \(I_C\) = 500 \(\mu\)A. \(V_{EE}\) = 22 V, \(R_E\) = 15 k\(\Omega\), \(R_C\) = 6.8 k\(\Omega\).

    5.7.3: Challenge Problems

    23. Determine the maximum and minimum values for \(I_C\) in Problem 1 if every resistor has a 10% tolerance.

    24. Determine the maximum and minimum values for \(V_{CE}\) in Problem 3 if every resistor has a 5% tolerance.

    25. Determine a value for \(R_E\) in the circuit of Figure \(\PageIndex{3}\) to set \(V_{CE}\) = 10 V. \(V_{CC}\) = 30 V, \(R_1\) = 12 k\(\Omega\), \(R_2\) = 3 k\(\Omega\), \(R_C\) = 8.2 k\(\Omega\).

    26. Derive Equation 5.16.

    27. Determine the the power drawn from the supply for the circuit of Problem 5. 28. Using a 15 volt power supply, design a bias circuit to create a very stable Q point of 2 mA and 5 volts.

    5.7.4: Computer Simulation Problems

    29. Perform a series of DC simulations to test the Q point stability versus \(\beta\) of the circuit of Problem 1.

    30. Perform a Monte Carlo simulation to investigate the Q point stability of the circuit of Problem 5 if the emitter resistor has a 10% tolerance.


    This page titled 5.7: Exercises is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by James M. Fiore via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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