Question

Consider the following circuit. Assume the threshold voltage of the N-FETs is Vthn 0.4V, and threshold voltage of the PFET is Vthp-0.6V. Assume, both PFETs and NFETs have same oxide thickness (tox 2nm), and v length (L22nm). Assume, supply voltage (VDD)-2.5% and mobility of NFET and PFET are given by: 나 = 1000 cm 2/V-s and μ,-0.5Hn. Assume, width of the N-FET is same of both inverter, and equal to Wn110nm. Width of PFETs (Wp) are also same for both inverters; however, Wp is NOT equal to Wn VoD 2.5V W. W 110nm w, = 110nm V: 0 to Voo Consider the following design scenarios. You need to use saturation current based model of delay (not RC delay) for this problem Design for Vw-0.5Voo 1. Compute width of PFETs (Wp) such that switching threshold of the inverters (VM 0.5VDD) [25 points] 2. Based on the design in problem 1, compute the ratio of low-to-high (tpLH) to high-to-low (tpHu) propagation delay of the first inverter i.e. compute tplH tpHL]. [25 points] Design for tpLH tpHL 3. Compute width of PFETs (Wp) required to achieveH[25 points] 4. Based on the design in problem 3, compute VM/VDD [25 points] Permittivity of free space Permittivity of silicon Permittivity of SiO2 8.854x10-1 F/cm 11.686 1.03x10-12 F/cm 3.90 345x1013 F/cm

Answer 1

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