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A bias source is depicted in Figure 10.1 where Q2 is twice the size of Q1. The other transistors are the same size as Q1. (a) State the basic mechanism of this bias source. (b) Derive the variation of the fractional temperature coefficient for the output current. (c) Determine the resistance R2 for the current bias reference circuit to obtain an output of 100μA and the resultant TCF at room temperature (T=300 K). Assume that the resistor temperature coefficient is 1500ppm/∘C. [(c) 180Ω, 1800ppm/∘C]

A bias source is depicted in Figure 10.1 where Q2 is twice the size of Q1. The other transistors are the same size as Q1. (a) State the basic mechanism of this bias source. (b) Derive the variation of the fractional temperature coefficient for the output current. (c) Determine the resistance R2 for the current bias reference circuit to obtain an output of 100μA and the resultant TCF at room temperature (T=300 K). Assume that the resistor temperature coefficient is 1500ppm/∘C. [(c) 180Ω, 1800ppm/∘C]

Please answer Q1 part(c)

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A bias source is depicted in Figure 10.1 where Q2 is twice the size of Q1. The other transistors are the same size as Q1. (a) State the basic mechanism of this bias source. (b) Derive the variation of the fractional temperature coefficient for the output current. (c) Determine the resistance R2 for the current bias reference circuit to obtain an output of 100μA and the resultant TCF at room temperature (T=300 K). Assume that the resistor temperature coefficient is 1500ppm/∘C. [(c) 180Ω, 1800ppm/∘C]

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