A simplified class-AB output stage with enhancement-mode MOSFETs is shown in Figure 8.26. The circuit parameters are \(V_{D D}=12 \mathrm{~V}\) and \(R_{L}=1 \mathrm{k} \Omega\). The transistor parameters are \(V_{T N}=-V_{T P}=1.5 \mathrm{~V}\) and \(K_{n}=K_{p}=4 \mathrm{~mA} / \mathrm{V}^{2}\).

(a) (i) Determine the value of \(V_{B B}\) such that \(i_{D n}=i_{D p}=1 \mathrm{~mA}\) when \(v_{I}=0\). (ii) What is the power dissipated in each transistor?

(b) (i) Determine the maximum output voltage such that \(M_{n}\) remains biased in the saturation region. (ii) What are the values of \(i_{D n}, i_{D p}, i_{L}\), and \(v_{I}\) for this case? (iii) Calculate the power dissipated in \(M_{n}, M_{p}\), and \(R_{L}\) for this case.

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VBB + +VpD Mn iDn ww VGSn 2 VI VBB VSGP 2 Mp ipp OVO RL -VDD Figure 8.26 MOSFET class-AB output stage