It is required to design the current-mirror- loaded differential MOS amplifier of Fig. 9.32 to obtain a differential gain of 50 V/V. The technology available provides unCox = 4upCox = 400 uA/V2, |Vt| = 0.5 V and |VA
Figure shows a folded-cascode CMOS amplifier utilizing a simple current source Q2, supplying a current 2I, and a cascaded current-source (Q4, Q5) supplying a current I. Assume, for simplicity, that all transistors have equal parameters, gm and r0. (50pt) (a) Give approximate expressions for all the resistances indicated (Ro1, Ro2, Ro3, Ro4, Ro5 and Rin3) (b) Find the amplifier output resistance Ro. (5pt) (c) Show that the short-circuit transconductance Gm is approximately equal to gm1. (5pt) (d) Find the overall voltage gain vo/vi and evaluate its value for the case gm1 = 2 mA/V and intrinsic gain, A0 = 20.
Perform a hand analysis to determine the small signal gain. ID1 = 1 mA and VDD = 5 V. The objective is to bias the circuit for maximum output swing. Figure 2: An NMOS common source amplifier with a PMOS current mirror active load.
8.75 Figure P8.75 shows a folded-cascode CMOS amplifier utilizing a simple current source Q2, supplying a current 2I, and a cascaded current-source (Q4, Q5) supplying a current I. Assume, for simplicity, that all transistors have equal parameters, gm and ro. (50pt) (a) Give approximate expressions for all the resistances indicated (b) Find the amplifier output resistance Ro. (5pt) (c) Show that the short-circuit transconductance Gm is approximately equal to gm1. Note that the short-circuit transconductance determined by short-circuiting vo to ground and finding the current that flows through the short circuit, Gmvi (5pt) (d) Find the overall voltage gain vo/vi and evaluate its value for the case gm1 = 2 mA/V and intrinsic gain, A0 = 30.