A simplified version of a common source amplifier is shown below. The MOSFET parameters are given beside the circuit diagram. a) Specify the value of VGG needed to produce a drain current ID = 0.1 mA. b) What is the output voltage vo(t)? include both DC and ac terms.
Calculate the differential-mode voltage gain, common-mode voltage gain, and common-mode rejection ratio (CMRR) of the fully-differential amplifier shown in Fig. 2. For CMRR calculation, neglect the mismatch in the two RB resistors but consider a relative mismatch of 5% between the two RD resistors. Assume the below values in calculations and neglect channel length modulation and body effect. VDD = 1.8 V, RB = 500 ohm, RS = 200 ohm, RD = 1.5 kohm, RL =5 kohm, unCox = 180 uA/V2, W = 20 um, L = 0.18 um, Vt = 0.6 V, ID = 450 uA. Fig. 2. Fully-differential common-source amplifier with source degeneration and resistive loads.
Calculate the symbolic small signal (VOUT /VIN) gain of the folded-cascode stage shown in Fig. 4 in terms of transistor parameters and the bias current Iss. Assume the current source Iss is ideal and all transistors are in saturation. Neglect body effect. Neglect channel length modulation except doing output impedance calculation; Transistor parameters are limited as those shown in Eq.1 and Eq.2; do not directly use gm and ro. (Hint: Try to draw the small signal model of the circuit to reach a straightforward solution.)
(a) Choose VB such that M1 is 300mV away from the triode region (VDS1 = VGS1-VTH1+300mV; M1 and M2 operate in Saturation region). (b) Calculate the small-signal voltage gain (VOUT/VIN). (c) Assume VB = 1.43 V, calculate the maximum output voltage swing to keep all transistors in saturation. Neglect channel length modulation. (d) Assume the maximum output swing is VOUT = 2.23 VPP, Calculate the swing at node X. In Fig. 2, assume (W/L)1 = 12 μm/0.18 μm, (W/L)2 = 24 μm/0.36 μm, ID1 = ID2 = 0.5 mA, and RD = 2 kΩ, VTH,N = 0.5 V, μnCox = 150 μA/V2, VDD = 3.3 V, λn = 0.1 V-1. Neglect body effect. Neglect channel length modulation except doing output impedance calculation.