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(a) Explain why a Bandgap voltage reference is preferred over a VBE-based voltage reference. (b) A Bandgap voltage reference is depicted in Figure 3. Derive the expression for VOUT in terms of VBE + KVT where K and VT are a constant and the thermal voltage, respectively. (c) Redesign the Bandgap voltage reference such that the current in the two transistors is not drawn from VCC. (d) The bipolar transistor Q1 and the bipolar op-amp A in the Bandgap voltage reference in Figure 3 are replaced by a PMOS transistor and a CMOS op-amp, respectively. Explain if these replacements are appropriate.

Please answer only question(b) and (d) thank you(a) Explain why a Bandgap voltage reference is preferred over a VBE-based voltage reference. (b) A Bandgap voltage reference is depicted in Figure 3. Derive the expression for VOUT in terms of VBE + KVT where K and VT are a constant and the thermal voltage, respectively. (c) Redesign the Bandgap voltage reference such that the current in the two transistors is not drawn from VCC. (d) The bipolar transistor Q1 and the bipolar op-amp A in the Bandgap voltage reference in Figure 3 are replaced by a PMOS transistor and a CMOS op-amp, respectively. Explain if these replacements are appropriate.

 

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(a) Explain why a Bandgap voltage reference is preferred over a VBE-based voltage reference. (b) A Bandgap voltage reference is depicted in Figure 3. Derive the expression for VOUT in terms of VBE + KVT where K and VT are a constant and the thermal voltage, respectively. (c) Redesign the Bandgap voltage reference such that the current in the two transistors is not drawn from VCC. (d) The bipolar transistor Q1 and the bipolar op-amp A in the Bandgap voltage reference in Figure 3 are replaced by a PMOS transistor and a CMOS op-amp, respectively. Explain if these replacements are appropriate.

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