{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

EE477-hw3-solutions-nazarian-spring2009

# EE477-hw3-solutions-nazarian-spring2009 - EE 477L Homework...

This preview shows pages 1–3. Sign up to view the full content.

1 EE 477L Homework 3 Solutions Spring ’09 Nazarian Lecture 9:30 Assigned: Tuesday Feb. 24, 2009 Due: March 6, 2009 EEB340 at 11am Show and explain your work clearly and in detail . Write the parameter units right beside their numerical values in your equations to show that the final result has the right unit (e.g., for N A =10 17 1/cm 3 write N A /q as 10 17 [cm -3 ] / 1.6×10 -19 [C] = 10 17 /(1.6×10 -19 ) [ 1/(cm 3 C) ] .) 1. Figure 1 shows an enhanced-load NMOS inverter. Assume γ =0.4, 2| φ f|=0.6V, V T0 =0.43V k n ’=115μA/V 2 and λ =0, (Note: all the following questions are adopting this information unless otherwise stated), calculate V OH , V OL , V M for the inverter and also the noise margin. Figure 1 Solution V OL : To calculate V OL , we set V IN = V DD = 2.5V. We expect V OUT to be low, so we can make the assumption that M2 will be saturated and M1 will be in the linear region.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
2 For M2: ' 2 2 2 2 2 2 . .( ) .(1 ) 2 n D GS T DS k W I V V V L λ = + , whereby 2 T V can be approximated as 2 T V derived in above process, which is equal to 2.5-1.765=0.735(V). For M1: ' 2 1 1 1 1 1 1 1 . .[2( ) ] 2 n D GS T DS DS k W I V V V V L = Set 2 D I = 1 D I , we get OUT V =0.285V. (Hint, more accurately, we can still consider the body effect of M2, and form 2 equations to solve both OUT V and 2 T V , which is also considered to be correct) V M : To calculate V M we set V M = V IN = V OUT ; therefore both M1 and M2 are in saturation region since their V G = V D , and we have following equations: ' 2 2 2 2 2 2 . .( ) .(1 ) 2 n D GS T DS k W I V V V L λ = + = ' 2 2 2 . .( 0.735) 2 n DD M k W V V L ' 2 1 1 1 1 1 . .( ) .(1 ) 2 n D GS T DS k W I V V V L λ = + = ' 2 1 0 1 . .( ) 2 n M T k W V V L Set 1 D I = 2 D I , we get M V = 0.984V. 2. Consider a standard CMOS inverter with V OH =2V, V OL =0.1V, while its V IH and V IL values are the same as those for the inverter in question 1. Comment on and compare the robustness of the two inverters.
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 7

EE477-hw3-solutions-nazarian-spring2009 - EE 477L Homework...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online