推 ketsu1109 :已收入精華區 11/24 02:28
課程名稱︰交換電路與邏輯設計
課程性質︰大二必修
課程教師︰李建模
開課學院:電資學院
開課系所︰電機系
考試日期(年月日)︰2009/11/13
考試時限(分鐘):110分
是否需發放獎勵金:是
(如未明確表示,則不予發放)
試題 :
Switching Circuits and Logic Design
Midterm Examination
1.(8%)Convert (25/3) to base 9. Truncate the final answer. Do all of the
arithmetic in decimal with accuracy to 2 decimal places (just ignore the
3rd decimal place).
2.(15%)In this problem, given the following circuit of input X, Y, and Z:
(這裡有個電路圖...我懶的畫了...)
(總之做出來是X(YZ'+Y'Z')+Y(XZ+X'Z') )
(a)(7%)Find the minimum sum of product expression for output F.
(b)(8%)Draw a circuit of input X,Y,Z to realize F by using two OR gates,two
AND gates, and one inverter only. All of gates should have two inputs except
the inverter. Note: There are three possible solutions. You just need to
write ONE solution.
3.(15%)Simplify the Boolean expression using the consensus theorem and/or
other theorems.
(a'+c'+d)(b+c'+d)(a+b+d)(a'+b+c)(a'+b+d)(a+b'+c+d')(a+b+c+d')
4.(22%)For the Boolean expression:
f(a,b,c,d)=sigma m(0,2,5,8,9,12,13)+ sigma d(10,11,14)
(Assume that a is the most significant bit and d is the least significant
bit. That means, a'b'c'd'=m1.)
(a)(10%)Find the minimum sum-of-product expression with Karnaugh Map.
Please also indicate which terms are essential prime implicants.
(b)(12%)Derive the two-level minimum NAND-NAND, NOR-OR, OR-NAND circuits
of f(a,b,c,d).
5.(15%)
(a)(12%)Find a minimum two-level, multiple-output OR-AND circuit to realize
f1(a,b,c,d)=bd'+a'd+cd'
f2(a,b,c,d)=b'c'+b'd+a'b
f3(a,b,c,d)=a'b+bd'+b'd
(b)(3%)Realize the same function with a minimum two-level NOR-NOR circuit.
6.(15%)
For the circuit given below, assume all the gates have propagation delay 1ns.
A---- W
AND ---------- X
Z---- NAND---------- Y
| B----- NAND--------
| A----- AND---------Z
| C---- |
| |
|--------------------------------------------------------|
(我竟然完成了這麼精美(?)的圖耶!!)
(a)(5%)Fill in the following chart with the 9 values corresponding to the
{0,1,x} three-valued simulation of a 2-input NAND gate, where "x" denotes
an unknown value.
NAND| 0 1 x
---------------
0 |
1 |
x |
(b)(5%)Complete the following truth table of function Z in terms of input
variables A,B, and C.
(Suggestion:Don't panic! Wheneveryou are not sure about the value of a
wire, treat it as an unknown. Three-valued simulation may help you
understand the circuit.)
ABC| Z
----------
000| 0
001|
010|
011|
100|
101|
110|
111|
(c)(2%)Can a static 1-hazard happen in Z? If yes, under what condition(
that is, fixing A,B,C to certain values for enough time and then
switching one of the inputs to its opposite value) can it happen?
(Suggestion: K-map based analysis does not work here because it's a
multi-level circuit. However, the mechanism for a static 1-hazard to
happen here is similar to that in a two-level circuit.)
(d)(3%)Complete the following timing diagram (from 3ns to 7ns).
(Assume A=W=X=1 and B=C=Y=Z=0 initally.)
|---------------
A| |--------------------
| --------------------------
B|---------|
| ------------------------------
C|-----|
|---------------
W|
|---------------
X|
|
Y|---------------
|
Z|---------------
|---------------------------------------------
0 1 2 3 4 5 6 7
7.(10%)
Let Boolean function f(A,B,C,D)=A'D'+A'C+AB'+AC'D, whose K-map is shown
below for your reference.
\ AB
CD \ 00 01 11 10
00 1 1 1
01 1 1
11 1 1 1
10 1 1 1
(a)(8%)Implement f using a 4-to-a MUX and 2-input AND/OR gates.
(Let variables A and B be the control variables of the MUX.
Assume a variable and its complement are available as inputs.)
(b)(2%)Suppose f is implemented with two function generators g and h
connected as shown below. Determine the functions of g(A,B,H) and
h(C,D). (There can be multiple solutions; however, showing one is enough.)
-------
A--| |
------- B--| |
C-------| | | g |-------G
| h |------| |
D-------| | H |-----|
|-----|
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※ 編輯: princeeeeeee 來自: 140.112.249.177 (11/24 00:37)