Name: Student D Number: Secton Number: 01/0/03/04 A/B Lecturer: Dr Jamaludn/ Dr Azn Wat/ Dr Jehana Ermy/ Prof Md Zan Table Number: ollege of Engneerng Department of Electroncs and ommuncaton Engneerng Test SEMESTER, AADEM YEAR 017/018 Subject ode : EEEB73 ourse Ttle : Electroncs Analyss & Desgn Date : 30 December 017 Tme Allowed : hours nstructons to the canddates: 1. Wrte your Name and Student D Number. ndcate your Secton Number and Lecturer s Name. Wrte also your Table Number.. Wrte all your answers usng pen. DO NOT USE PENL except for the dagram. 3. ANSWER ALL QUESTONS. Show clearly all your calculatons. Eery alue must be wrtten wth ts correct Unt. 4. WRTE ALL YOUR ANSWERS ON THS QUESTON PAPER. NOTE: DO NOT OPEN THE QUESTON PAPER UNTL NSTRUTED TO DO SO. GOOD LUK! Queston Number Marks Q1a Q1b-c Qa-d Qe Q3 Q4a Q4b Total Page 1
QUESTON 1 [0 marks] A BJT dfferental amplfer shown n Fgure 1 s based by a constant current source wth Q = 0.3 ma. The dfferental amplfer s to be redesgned wth an acte load. The acte load to be used s a BJT Wlson current source usng pnp transstors. The transstor parameters are β = 10, BE (on) = EB (on) = 0.7, AN = 100, and AP = 10. (a) Draw the new dfferental amplfer crcut added wth the acte load. Label the crcut correctly and clearly wth approprate symbols and numberng for transstors used n crcut. [4 marks] (b) alculate the dfferental-mode oltage gan, (A d ), of the new crcut. [1 marks] (c) alculate the dfferental-mode oltage gan, (A d ), of the dfferental amplfer crcut f the acte load s changed to a three-transstor current source. Ge your comment about alues of A d for the dfferental amplfer crcut usng Wlson current source and threetransstor current source acte loads. [4 marks] Answers for Queston 1 Fgure 1 Page
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QUESTON [35 marks] Fgure shows a dfferental amplfer crcut wth acte loads and based by a current source usng MOSFET. Transstors M 1 and M are dren nto saturaton wth DS (sat)= 1.1. The acte load transstors (M 3 and M 4 ) are matched wth parameters K p = 0.1 ma/, TP = -, and λ p = 0.0-1. Transstors M 5, M 6 and M 7 are dentcal. All the NMOS transstors hae the same K n = 0. ma/, TN =, and λ n = 0.015-1. (a) Determne 1, Q, and D1 when 1 = = 0. [6 marks] (b) Determne the one-sded dfferental mode oltage gan (A d ) for the dfferental amplfer f R L = 100 kω. [9 marks] (c) t s requred that the MRR of the crcut to be 60 db. What s the common mode oltage gan (A cm )? [3 marks] (d) Suggest ways to mproe the MRR for the crcut n the Fgure. [ marks] (e) The MOSFET dfferental amplfer wth acte load n the Fgure s replaced wth the MOSFET dfferental amplfer wth ascode acte load. Draw and label clearly all the transstors used n the new crcut. [15 marks] Fgure Page 4
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Extra page for Answers ndcate queston number(s) Page 6
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QUESTON 3 [0 marks] onsder the crcut shown n Fgure 3. Study the Fgure 1 thoroughly. Wth supply oltage ±10 and crcut parameters R 1 = 19.3 kω, R = R 3 = 0.1 kω, and R 4 = 5 kω t can be calculated that the alue of Q s 0.307 ma. Assume the quescent alues 7 = Q ; 1 = E1 = = E ; BE (on) = 0.7, β = 10, Early oltage s 100 for Q 7 and Q 11 ; and O = 0 when 1 = = 0. R s the nput resstance of the Darlngton Par whle R L7 s the effecte resstance connected between collector of Q 7 and sgnal ground. alculate the small sgnal oltage gan of the Darlngton Par (A ) by usng the followng relatonshp: A o3 b6 R 1 ( ro 7 RL7 ) [0 marks] Answers for Queston 3 Fgure 3 Page 8
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QUESTON 4 [5 marks] (a) Draw a class-a output stage constructed usng npn emtter follower wth load R L and based by a three-transstor current snkng current source. The oerall crcut s connected to supply oltages of + = +5 and - = -5. [5 marks] (b) A class-ab output stage wth BJTs s shown n Fgure 4. Reerse saturaton current for eery transstor s S = 10-15 A. Assume + = +6 and - = -6. Let R L = 1 kω and BB = 1.40. For the case of the output oltage O = -4 : () Determne L, p, n, and. [1 marks] () alculate the power dsspated n transstor Q n and Q p. [8 marks] Answers for Queston 4 Fgure 4 Page 10
Answers for Queston 4 (ontnued) Page 11
Page 1 APPENDX A) BAS FORMULA FOR TRANSSTOR BJT MOSFET B) HYBRD-π EQUALENT RUTS BJT MOSFET ) QUADRAT FORMULA A A B B x Bx Ax 4 0 DQ o DQ p m DQ n m p ox p p TP SG p D TP SG SD n ox n n TN GS n D TN GS DS r K g K g L W k L W K K L W k L W K K 1 MOSFET ;P MOSFET ; N sgnal ;Small ] [ (sat) MOSFET ;P ] [ (sat) MOSFET ; N ' ' 6 m sgnal ;Small 1 ;PNP NPN ; / / T Q A o Q T T Q m m B E E B S S r r g r g e e T EB T BE