Τεχνολογία Προηγμένων Ψηφιακών Κυκλωμάτων & Συστημάτων Καθηγητής: Παπαδόπουλος Γ. Πιτσιώρης Γεώργιος 4830 Ε’ Έτος
Digital Integrated Circuits Jan Rabaey
Chapter 4: Problem 4.1
Δεδομένα για Polysilicon Parallel-plate capacitance to substrate: fF/μm 2 Parallel-plate capacitance to substrate: fF/μm 2 Fringing capacitance to substrate : 0.054fF/μm Fringing capacitance to substrate : 0.054fF/μm Sheet resistance : 4 Ω/sq Sheet resistance : 4 Ω/sq
Ι av = C total * ΔV/ΔT= =(4*100fF+7*C ws )*5Volts/5nsec= =400fF+7*(5mm*3μm*0.088fF/μm 2 +2*5mm*0.054fF/μm)Volts/nsec= =400fF+7*(1320fF+540fF)Volts/nsec==13.42mA I av,90% =0.9*13.42mA=12.078mA
Π-Network model για RC distributed Line Π-Network model για RC distributed Line
Έτσι διαμορφώνεται το ισοδύναμο κύκλωμα
Capacitors : C ws =5mm*3μm*0.088fF/μm 2 +2*5mm* Capacitors : C ws =5mm*3μm*0.088fF/μm 2 +2*5mm* 0.054fF/μm=( )fF=1860fF Resistors : Resistors : R ws =5mm/3μm*4Ω/sq=6.67kΩ
Το dominant time constant είναι το elmore delay (first order time constant) Το dominant time constant είναι το elmore delay (first order time constant) Penfield-Rubenstein-Horowitz δίνουν μεθοδολογία για tree RC networks Penfield-Rubenstein-Horowitz δίνουν μεθοδολογία για tree RC networks τ=1.5* C ws *(R ws +R ws +2*R ws )+(0.5*C ws +100fF)* τ=1.5* C ws *(R ws +R ws +2*R ws )+(0.5*C ws +100fF)* (R ws +R ws +2*R ws +3*R ws )=9.5*C ws *R ws +7*R ws *100fF= 9.5*1860fF*6.67kΩ+7*100fF*6.67kΩ= nsec
Λύση με άλλα δεδομένα Parallel-plate capacitance to substrate: fF/μm 2 Parallel-plate capacitance to substrate: fF/μm 2 Fringing capacitance to substrate : 0.043fF/μm Fringing capacitance to substrate : 0.043fF/μm Sheet resistance : 4 Ω/sq Sheet resistance : 4 Ω/sq
Αποτελέσματα Ι av = C total * ΔV/ΔT= Ι av = C total * ΔV/ΔT= =(4*100fF+7*C ws )*5Volts/5nsec= =400fF+7*(5mm*3μm*0.058fF/μm 2 +2*5mm*0.043fF/μm)Volts/nsec= =400fF+7*(870fF+430fF)Volts/nsec= =9.5mA I av,90% =0.9*9.5mA=8.55mA I av,90% =0.9*9.5mA=8.55mA
Αποτελέσματα Capacitors : C ws =( )fF=1300fF Capacitors : C ws =( )fF=1300fF Resistors : R ws =5mm/3μm*4Ω/sq=6.67kΩ Resistors : R ws =5mm/3μm*4Ω/sq=6.67kΩ τ=1.5* C ws *(R ws +R ws +2*R ws )+(0.5*C ws +100fF)* τ=1.5* C ws *(R ws +R ws +2*R ws )+(0.5*C ws +100fF)* (R ws +R ws +2*R ws +3*R ws )=9.5*C ws *R ws +7*R ws *100fF= 9.5*1300fF*6.67kΩ+7*100fF*6.67kΩ=87nsec