ece 2280 HW4 electronics http://www.ece.utah.edu/

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ECE2280 Homework #4 1. The terminal voltages of various npn transistors are measured during operation in their respective circuits with the following results:

Case E B C Mode 1 0 0.7 0.7

2 0 0.8 0.1

3 -0.7 0 0.7

4 -0.7 0 -0.6

5 -2.7 -2.0 0

6 0 0 5

2. Use |VBE|=0.7, β=100. Find IB, IC, IE, VB, VC, VE.

3. Use |VBE|=0.7, β=100. Find IB, IC, IE, VB, VC, VE.

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4. Use |VBE|=0.7, β=100. Find IB, IC, IE, VB, VC, VE. 5. Use |VBE|=0.7, β=100. Find IB, IC, IE, VB, VC, VE.

6. For the circuit on the right. Use |VBE|=0.7, β=100, VT=25mV. Find IB4, IC4, IE4, VB4, VC4, VE4. Assume capacitors act as opens for DC analysis.

-10V

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7. Use the circuit below. Use |VBE|=0.7, β=100, VT=25mV. Find IB1, IB2, IB3, IC3, IE3, VB1, VC1, VB2, VB3, VE3. Vs is an AC source. Assume capacitors act as an open for DC analysis. 8. Use |VBE|=0.7, β=100. Find the DC values: IB, IC, IE, VB, VC, VE.

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9. Find IE, VE, IB, VB, IC, VC Let β=100.

10. Let β=99. Find the DC values for IE, VE, IB, VB, IC, VC. Verify your assumption.