For the class-AB output stage in Figure 8.36, the parameters are: \(V^{+}=24 \mathrm{~V}, V^{-}=-24 \mathrm{~V}, R_{L}=20 \Omega\), and \(I_{\text {Bias }}=10 \mathrm{~mA}\). The diode and transistor parameters are \(I_{S}=2 \times 10^{-12} \mathrm{~A}\). The transistor current gains are \(\beta_{n}=20\) and \(\beta_{p}=5\) for the npn and pnp devices, respectively.

(a) For \(v_{O}=0\), determine \(V_{B B}\), and the quiescent collector current and baseemitter voltage for each transistor.

(b) An average power of 10 watts is to be delivered to the load. Determine the quiescent collector current in each transistor and the instantaneous power dissipated in \(Q_{2}, Q_{5}\), and \(R_{L}\) when the output voltage is at its peak negative amplitude.

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V+ V+ IBias Q D D2 VBB D3 Q2 Q3 Q4 Qs Q6 RL Figure 8.36 Class-AB output stage with Darlington pairs