数字电路和系统设计课后习题集答案解析
1.1将下列各式写成按权展开式：（352.6）10=3×102+5×101+2×100+6×10-1（101.101）2=1×22+1×20+1×2-1+1×2-3（54.6）8=5×81+54×80+6×8-1（13A.4F）16=1×162+3×161+10×160+4×16-1+15×16-21.2按十进制0~17的次序，列表填写出相应的二进制、八进制、十六进制数。
解：略1.3二进制数00000000~11111111和0000000000~1111111111分别可以代表多少个数？解：分别代表28=256和210=1024个数。
1.4将下列个数分别转换成十进制数：（1111101000）2，（1750）8，（3E8）16解：（1111101000）2=（1000）10（1750）8=（1000）10（3E8）16=（1000）101.5将下列各数分别转换为二进制数：（210）8，（136）10，（88）16解：结果都为：（10001000）21.6将下列个数分别转换成八进制数：（111111）2，（63）10，（3F）16解：结果都为（77）81.7将下列个数分别转换成十六进制数：（11111111）2，（377）8，（255）10解：结果都为（FF）161.8转换下列各数，要求转换后保持原精度：解：（1.125）10=（1.0010000000）10——小数点后至少取10位（0010 1011 0010）2421BCD=（11111100）2（0110.1010）余3循环BCD码=（1.1110）21.9用下列代码表示（123）10，（1011.01）2：解：（1）8421BCD码：（123）10=（0001 0010 0011）8421BCD（1011.01）2=（11.25）10=（0001 0001.0010 0101）8421BCD（2）余3 BCD码（123）10=（0100 0101 0110）余3BCD（1011.01）2=（11.25）10=（0100 0100.0101 1000）余3BCD1.10已知A=（1011010）2，B=（101111）2，C=（1010100）2，D=（110）2（1）按二进制运算规律求A+B，A-B，C×D，C÷D，（2）将A、B、C、D转换成十进制数后，求A+B，A-B，C×D，C÷D，并将结果与（1）进行比较。
解：（1）A+B=（10001001）2=（137）10A-B=（101011）2=（43）10C×D=（111111000）2=（504）10C÷D=（1110）2=（14）10（2）A+B=（90）10+（47）10=（137）10A-B=（90）10-（47）10=（43）10C×D=（84）10×（6）10=（504）10C÷D=（84）10÷（6）10=（14）10两种算法结果相同。
1.11试用8421BCD码完成下列十进制数的运算。
解：（1）5+8=（0101）8421BCD+（1000）8421BCD=1101 +0110=（1 0110）8421BCD=13（2）9+8=（1001）8421BCD+（1000）8421BCD=1 0001+0110=（1 0111）8421BCD=17（3）58+27=（0101 1000）8421BCD+（0010 0111）8421BCD=0111 1111+ 0110=（1000 0101）=858421BCD（4）9-3=（1001）8421BCD-（0011）8421BCD=（0110）8421BCD=6（5）87-25=（1000 0111）8421BCD-（0010 0101）8421BCD=（0110 0010）8421BCD=62（6）843-348 =（1000 0100 0011）8421BCD-（0011 0100 1000）8421BCD=0100 1111 1011- 0110 0110=（0100 1001 0101）8421BCD=4951.12试导出1位余3BCD码加法运算的规则。
解：1位余3BCD码加法运算的规则加法结果为合法余3BCD码或非法余3BCD码时，应对结果减3修正[即减(0011)2]；相加过程中，产生向高位的进位时，应对产生进位的代码进行“加33修正”[即加(0011 0011)2]。
2.1有A、B、C三个输入信号，试列出下列问题的真值表，并写出最小项表达式∑m（）。
（1）如果A、B、C均为0或其中一个信号为1时。
输出F=1，其余情况下F=0。
（2）若A、B、C出现奇数个0时输出为1，其余情况输出为0。
（3）若A、B、C有两个或两个以上为1时，输出为1，其余情况下，输出为0。
解：F1(A,B,C)=∑m（0，1，2，4）F2(A,B,C)=∑m（0，3，5，6）F3(A,B,C)=∑m（3，5，6，7）2.2试用真值表证明下列等式：（1）A⎺B+B⎺C+A⎺C=ABC+⎺A⎺B⎺C（2）⎺A⎺B+⎺B⎺C+⎺A⎺C=AB BC AC真值表相同，所以等式成立。
（2）略2.3对下列函数，说明对输入变量的哪些取值组合其输出为1？（1）F（A,B,C）=AB+BC+AC（2）F（A,B,C）=(A+B+C)(⎺A+⎺B+⎺C)（3）F（A,B,C）=(⎺AB+⎺BC+A⎺C)AC解：本题可用真值表、化成最小项表达式、卡诺图等多种方法求解。
（1）F输出1的取值组合为：011、101、110、111。
（2）F输出1的取值组合为：001、010、011、100、101、110。
（3）F输出1的取值组合为：101。
2.4试直接写出下列各式的反演式和对偶式。
(1)F(A,B,C,D,E)=[(A⎺B+C)·D+E]·B(2) F(A,B,C,D,E)=AB+⎺C⎺D+BC+⎺D+⎺CE+B+E(3) F(A,B,C)=⎺A⎺B+C ⎺AB C解：(1) ⎺F=[(⎺A+B)·⎺C+⎺D]·⎺E+⎺BF'=[(A+⎺B)·C+D]·E+B(2) ⎺F=(⎺A+⎺B)(C+D)·(⎺B+⎺C)·D·(C+⎺E)·⎺B·⎺EF'=(A+B)(⎺C+⎺D)·(B+C)·⎺D·(⎺C+E)·B·E(3)⎺F=(A+B)·⎺C+ A+⎺B+CF'=(⎺A+⎺B)·C+⎺A+B+⎺C2.5用公式证明下列等式：(1)⎺A⎺C+⎺A⎺B+BC+⎺A⎺C⎺D=⎺A+BC(2)AB+⎺AC+(⎺B+⎺C) D=AB+⎺AC+D(3)⎺BC⎺D+B⎺CD+ACD+⎺AB⎺C⎺D+⎺A⎺BCD+B⎺C⎺D+BCD=⎺BC+B⎺C+BD(4)A⎺B⎺C+BC+BC⎺D+A⎺BD=⎺A + B +⎺C+⎺D证明：略2.6已知⎺ab+a⎺b=a⊕b,⎺a⎺b+ab=a b,证明：（1）a⊕b⊕c=a b c（2）a⊕b⊕c=⎺a ⎺b ⎺c证明：略2.7试证明：（1）若⎺a⎺b+ a b=0则a x+b y=a⎺x + b⎺y（2）若⎺a b+a⎺b=c，则⎺a c + a⎺c=b证明：略2.8将下列函数展开成最小项之和：（1）F（ABC）=A+BC（2）F（ABCD）=（B+⎺C）D+(⎺A+B) C（3）F(ABC)=A+B+C+⎺A+B+C解：（1）F（ABC）=∑m(3,4,5,6)(2) F（ABCD）=∑m(1,3,5,6,7,9,13,14,15)(3) F(ABC)=∑m(0,2,6)2.9将题2.8中各题写成最大项表达式，并将结果与2.8题结果进行比较。
解：（1）F（ABC）=∏M(0,1,2)(2) F（ABCD）=∏M(2,4,8,10,11,12)(3)F（ABC）=∏M(1,3,4,5,7)2.10试写出下列各函数表达式F的⎺F和F'的最小项表达式。
（1）F=ABCD+ACD+B⎺C⎺D（2）F=A⎺B+⎺AB+BC解：（1）⎺F=∑m(0,1,2,3,5,6,7,8,9,10,13,14)F'=∑m(1,2,5,6,7,8,9,10,12,13,14,15)(2) ⎺F=∑m(0,1,2,3,12,13)F'=∑m(2,3,12,13,14,15)2.11试用公式法把下列各表达式化简为最简与或式（1）F=A+AB⎺C+ABC+BC+B解：F =A+B(2) F=(A+B)(A+B+C)(⎺A+C)(B+C+D)解：F'=AB+⎺AC(3) F=AB+⎺A⎺B •BC+⎺B⎺C解：F=AB+⎺B⎺C+⎺AC或：F=⎺A⎺B+A⎺C+BC(4) F=A⎺C⎺D+BC+⎺BD+A⎺B+⎺AC+⎺B⎺C解：F=A⎺D+C+⎺B(5) F=AC+⎺BC+B(A⎺C+⎺AC)解：F=AC+⎺BC2.12用卡诺图把下列函数化简为最简与或式（1）F(A,B,C)=∑m(0,1,2,4,5,7)解：F=⎺B+⎺A⎺C+AC图略（2）F(A,B,C,D)=∑m(0,2,5,6,7,9,10,14,15)解：F=A⎺B⎺CD+⎺A⎺B⎺D+⎺ABD+BC+C⎺D图略（3）F(A,B,C,D)=∑m(0,1,4,7,9,10,13) +∑φ(2,5,8,12,15)解：F=⎺C+BD+⎺B⎺D图略（4）F(A,B,C,D)=∑m(7,13,15) 且⎺A⎺B⎺C=0, ⎺AB⎺C=0, ⎺A⎺BC=0解：F(A,B,C,D)=BD图略(5) F(A,B,C,D)=AB⎺C+A⎺B⎺C+⎺A⎺BC⎺D+A⎺BC⎺D且ABCD不可同时为1或同时为0 解：F(A,B,C,D)=⎺B⎺D+A⎺C图略（6）F(A,B,C,D)=∏M (5,7,13,15)解：F=⎺B+⎺D图略（7）F(A,B,C,D)=∏M (1,3,9,10,14,15)解：F=⎺A⎺D+⎺AB+⎺C⎺D+B⎺C+A⎺BCD图略（8）F(A,B,C,D,E)=∑m(0,4,5,6,7,8,11,13,15,16,20,21,22,23,24,25,27,29,31)解：F=⎺C⎺D⎺E+⎺BC+CE+BDE+ABE图略2.13用卡诺图将下列函数化为最简或与式（1）F(A,B,C)=∑m(0,1,2,4,5,7)解：F=(A+⎺B+⎺C)(⎺A+⎺B+C)图略（2）F(A,B,C)=∏M (5,7,13,15)解：F=(⎺B+⎺D)图略2.14已知：F1(A,B,C)=∑m(1,2,3,5,7) +∑φ(0,6)，F2(A,B,C)=∑m(0,3,4,6) +∑φ(2,5)，求F=F1⊕F2的最简与或式解：F=A+⎺B4.1分析图4.1电路的逻辑功能解：（1）推导输出表达式（略）(2) 列真值表（略）解：(1)从输入端开始，逐级推导出函数表达式。
数字电路习题及答案
·数字电路与系统-习题答案1第1 章数字逻辑基础1.1 什么是数字电路？与模拟电路相比，数字电路具有哪些特点？答：处理数字信号并能完成数字运算的电路系统称为数字电路。
特点：采用二进制，结构简单易于集成；可用于数值计算和逻辑运算；抗干扰，精度高；便于长期存储和远程传输，保密性好，通用性强。
1.3 把下列二进制数转换成十进制数。
（1）(11000101)2 = (197)10（2）(0.01001)2 = (0.28125)10（3）(1010.001)2 = (10.125)101.4 把下列十进制数转换成二进制数。
（1）(12.0625)10 = (1100.0001)2（2）(127.25)10 = (1111111.01)2（3）(101)10 = (1100101)21.5 把二进制数(110101111.110)2分别转换成十进制数、八进制数和十六进制数。
答：(110101111.110)2 =(431.75)10 =(657.6)8 =(1AF.C)161.6 把八进制数(623.77)8分别转换成十进制数、十六进制数和二进制数。
答：(623.77)8 =(403.98)10 =(193.FC)16 =(110010011.111111)21.7 把十六进制数(2AC5.D)16分别转换成十进制数、八进制数和二进制数。
答：(2AC5.D)16 =(10949.81)10 =(25305.64)8 =(10101011000101.1101)21.8 把十进制数(432.13)10转换成五进制数。
答：(432.13)10 =(3212.0316)51.9 用8421BCD 码表示下列十进制数。
（1）(42.78)10 =(0100 0010.0111 1000)8421BCD（2）(103.65)10 =(0001 0000 0011.0110 0101)8421BCD（3）(9.04)10 =(1001.0000 0100)8421BCD数字电路与系统-习题答案21.10 把下列8421BCD 码表示成十进制数。
数字集成电路--电路、系统与设计（第二版）课后练习题第六.
数字集成电路--电路、系统与设计（第⼆版）课后练习题第六.Digital Integrated Circuits - 2nd Ed 11 DESIGN PROJECT Design, lay out, and simulate a CMOS four-input XOR gate in the standard 0.25 micron CMOS process. You can choose any logic circuit style, and you are free to choose how many stages of logic to use: you could use one large logic gate or a combination of smaller logic gates. The supply voltage is set at 2.5 V! Your circuit must drive an external 20 fF load in addition to whatever internal parasitics are present in your circuit. The primary design objective is to minimize the propagation delay of the worst-case transition for your circuit. The secondary objective is to minimize the area of the layout. At the very worst, your design must have a propagation delay of no more than 0.5 ns and occupy an area of no more than 500 square microns, but the faster and smaller your circuit, the better. Be aware that, when using dynamic logic, the precharge time should be made part of the delay. The design will be graded on themagnitude of A × tp2, the product of the area of your design and the square of the delay for the worst-case transition.。
《数字电路与系统设计》第6章习题答案
l ee t h e \1210101…X/Z0/01/0X/Z11…100…6.3对下列原始状态表进行化简： (a)解：1）列隐含表： 2）进行关联比较3）列最小化状态表为：a/1b/0b b/0a/0aX=1X=0N(t)/Z(t)S(t)解：1）画隐含表： 2）进行关联比较： 6.4 试画出用MSI 移存器74194构成8位串行 并行码的转换电路（用3片74194或2片74194和一个D 触发器）。
l ee t-h e \r 91行''' 试分析题图6.6电路，画出状态转移图并说明有无自启动性。
解：激励方程：略 状态方程：略状态转移图 该电路具有自启动性。
6.7 图P6.7为同步加/减可逆二进制计数器，试分析该电路，作出X=0和X=1时的状态转移表。
解：题6.7的状态转移表X Q 4nQ 3nQ 2nQ 1nQ 4n +1Q 3n +1Q 2n +1Q 1n +1Z 0 0 0 0 0 1 1 1 1 1 0 1 1 1 1 1 1 1 0 0 0 1 1 1 0 1 1 0 1 0 0 1 1 0 1 1 1 0 0 0 0 1 1 0 0 1 0 1 1 0 0 1 0 1 1 1 0 1 0 0 0 1 0 1 0 1 0 0 1 0 0 1 0 0 1 1 0 0 0 0 0 1 0 0 0 0 1 1 1 0 0 0 1 1 1 0 1 1 0 0 0 0 1 1 0 0 1 0 1 0 0 0 1 0 1 0 1 0 0 0 0 0 1 0 0 0 0 1 1 0 0 0 0 1 1 0 0 1 0 0 0 0 0 1 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 1 1 0 0 0 0 0 0 0 1 0 1 0 0 0 1 0 0 1 0 0 1 0 0 1 0 0 0 1 1 0 1 0 0 1 1 0 1 0 0 0 1 0 1 0 0 0 1 0 1 0 1 0 1 0 1 0 1 1 0 0 1 0 1 1 0 0 1 1 1 0 1 0 1 1 1 1 0 0 0 0 1 1 0 0 0 1 0 0 1 0 1 1 0 0 1 1 0 1 0 0 1 1 0 1 0 1 0 1 1 0 1 1 0 1 1 1 1 0 0 0 1 1 1 0 0 1 1 0 1 0 1 1 1 0 1 1 1 1 0 0 1 1 1 1 0 1 1 1 1 1 11 1116.8分析图6.8电路，画出其全状态转移图并说明能否自启动。
【精品】数字集成电路电路、系统与设计第二版课后练习题第六章CMOS组合逻辑门的设计
【精品】数字集成电路--电路、系统与设计(第二版)课后练习题第六章CMOS组合逻辑门的设计第六章 CMOS组合逻辑门的设计1.为什么CMOS电路逻辑门的输入端和输出端都要连接到电源电压？CMOS电路采用了MOSFET（金属氧化物半导体场效应管）作为开关元件，其中N沟道MOSFET（NMOS）和P沟道MOSFET（PMOS）分别用于实现逻辑门的输入和输出。
NMOS和PMOS都需要连接到电源电压，以使其能够正常工作。
输入端连接到电源电压可以确保信号在逻辑门中正常传递，输出端连接到电源电压可以确保输出信号的正确性和稳定性。
2.为什么在CMOS逻辑门中要使用两个互补的MOSFET？CMOS逻辑门中使用两个互补的MOSFET是为了实现高度抗干扰的逻辑功能。
其中，NMOS和PMOS分别用于实现逻辑门的输入和输出。
NMOS和PMOS的工作原理互补，即当NMOS导通时，PMOS截止，当PMOS导通时，NMOS截止。
这样的设计可以在逻辑门的输出上提供高电平和低电平的稳定性，从而提高逻辑门的抗干扰能力。
3.CMOS逻辑门的输入电压范围是多少？CMOS逻辑门的输入电压范围通常是在0V至电源电压之间，即在低电平和高电平之间。
在CMOS逻辑门中，低电平通常定义为输入电压小于0.3Vdd（电源电压的30%），而高电平通常定义为输入电压大于0.7Vdd（电源电压的70%）。
4.如何设计一个基本的CMOS逻辑门？一个基本的CMOS逻辑门可以由一个NMOS和一个PMOS组成。
其中，NMOS的源极连接到地，栅极连接到逻辑门的输入，漏极连接到PMOS的漏极；PMOS的源极连接到电源电压，栅极连接到逻辑门的输入，漏极连接到输出。
这样的设计可以实现逻辑门的基本功能。
5.如何提高CMOS逻辑门的速度？可以采取以下方法来提高CMOS逻辑门的速度：•减小晶体管的尺寸：缩小晶体管的尺寸可以减小晶体管的电容和电阻，从而提高逻辑门的响应速度。
•优化电源电压：增加电源电压可以提高晶体管的驱动能力，从而加快逻辑门的开关速度。
数字逻辑电路与系统设计蒋立平主编习题解答
第4章习题及解答用门电路设计一个4线—2线二进制优先编码器。
编码器输入为3210A A A A ，3A 优先级最高，0A 优先级最低，输入信号低电平有效。
输出为10Y Y ，反码输出。
电路要求加一G 输出端，以指示最低优先级信号0A 输入有效。
题 解：根据题意，可列出真值表，求表达式，画出电路图。
其真值表、表达式和电路图如图题解所示。
由真值表可知3210G A A A A =。
(a)0 0 0 00 0 0 10 0 1 00 0 1 10 1 0 00 1 0 10 1 1 00 1 1 11 0 0 0 1 0 0 11 0 1 01 0 1 11 1 0 01 1 0 11 1 1 01 1 1 10000000000000000000000000010100011111010110000103A 2A 1A 0A 1Y 0Y G真值表≥1&1Y 3A 2A 1&&1A 0Y &1GA 00 01 11 100010001111000000001101113A 2A 1A 0A 03231Y A A A A =+00 01 11 1000000011110001000011103A 2A 1A 0A 132Y A A =(b) 求输出表达式(c) 编码器电路图图 题解4.1试用3线—8线译码器74138扩展为5线—32线译码器。
译码器74138逻辑符号如图（a ）所示。
题 解：5线—32线译码器电路如图题解所示。
&&&&11EN01234567BIN/OCTENY 0&G 1G 2AG 2B42101234567BIN/OCTEN&G 1G 2A G 2B42101234567BIN/OCT EN&G 1G 2A G 2B42101234567BIN/OCT EN&G 1G 2A G 2B421A 0A 1A 2A 3A 4Y 7Y 8Y 15Y 16Y 23Y 24Y 31图 题解4.3写出图所示电路输出1F 和2F 的最简逻辑表达式。
资料：蒋立平版数字逻辑电路与系统设计习题答案
蒋立平版数字逻辑电路与系统设计第1章题库及解答1.1 将下列二进制数转换为等值的十进制数。
（1）（11011）2 （2）（10010111）2（3）（1101101）2 （4）（11111111）2（5）（0.1001）2（6）（0.0111）2（7）（11.001）2（8）（101011.11001）2题1.1 解：（1）（11011）2 =（27）10 （2）（10010111）2 =（151）10（3）（1101101）2 =（109）10 （4）（11111111）2 =（255）10（5）（0.1001）2 =（0.5625）10（6）（0.0111）2 =（0.4375）10（7）（11.001）2=（3.125）10（8）（101011.11001）2 =（43.78125）10 1.3 将下列二进制数转换为等值的十六进制数和八进制数。
（1）（1010111）2 （2）（110111011）2（3）（10110.011010）2 （4）（101100.110011）2题1.3 解：（1）（1010111）2 =（57）16 =（127）8（2）（110011010）2 =（19A）16 =（632）8（3）（10110.111010）2 =（16.E8）16 =（26.72）8（4）（101100.01100001）2 =（2C.61）16 =（54.302）81.5 将下列十进制数表示为8421BCD码。
（1）（43）10 （2）（95.12）10（3）（67.58）10 （4）（932.1）10题1.5 解：（1）（43）10 =（01000011）8421BCD（2）（95.12）10 =（10010101.00010010）8421BCD（3）（67.58）10 =（01100111.01011000）8421BCD（4）（932.1）10 =（100100110010.0001）8421BCD1.7 将下列有符号的十进制数表示成补码形式的有符号二进制数。
数字逻辑电路及系统设计习题答案
第1章习题及解答1.1 将下列二进制数转换为等值的十进制数。
（1）（11011）2 （2）（10010111）2（3）（1101101）2 （4）（11111111）2（5）（0.1001）2（6）（0.0111）2（7）（11.001）2（8）（101011.11001）2题1.1 解：（1）（11011）2 =（27）10 （2）（10010111）2 =（151）10（3）（1101101）2 =（109）10 （4）（11111111）2 =（255）10（5）（0.1001）2 =（0.5625）10（6）（0.0111）2 =（0.4375）10（7）（11.001）2=（3.125）10（8）（101011.11001）2 =（43.78125）101.3 将下列二进制数转换为等值的十六进制数和八进制数。
（1）（1010111）2 （2）（110111011）2（3）（10110.011010）2 （4）（101100.110011）2题1.3 解：（1）（1010111）2 =（57）16 =（127）8（2）（110011010）2 =（19A）16 =（632）8（3）（10110.111010）2 =（16.E8）16 =（26.72）8（4）（101100.01100001）2 =（2C.61）16 =（54.302）81.5 将下列十进制数表示为8421BCD码。
（1）（43）10 （2）（95.12）10（3）（67.58）10 （4）（932.1）10题1.5 解：（1）（43）10 =（01000011）8421BCD（2）（95.12）10 =（10010101.00010010）8421BCD（3）（67.58）10 =（01100111.01011000）8421BCD（4）（932.1）10 =（100100110010.0001）8421BCD1.7 将下列有符号的十进制数表示成补码形式的有符号二进制数。
数字电路与逻辑设计习题及参考答案全套
数字电路与逻辑设计习题及参考答案一、选择题1. 以下表达式中符合逻辑运算法则的是 D 。
A.C ·C=C 2B.1+1=10C.0<1D.A+1=12. 一位十六进制数可以用 C 位二进制数来表示。
A . １B . ２C . ４D . 163. 当逻辑函数有n 个变量时，共有 D 个变量取值组合？A. nB. 2nC. n 2D. 2n4. 逻辑函数的表示方法中具有唯一性的是 A 。
A .真值表 B.表达式 C.逻辑图 D.状态图5. 在一个8位的存储单元中，能够存储的最大无符号整数是 D 。
A .（256）10B .（127）10C .（128）10D .（255）106.逻辑函数F=B A A ⊕⊕)( = A 。
A.BB.AC.B A ⊕D. B A ⊕7．求一个逻辑函数F 的对偶式，不可将F 中的 B 。
A .“·”换成“+”，“+”换成“·”B.原变量换成反变量，反变量换成原变量C.变量不变D.常数中“0”换成“1”，“1”换成“0”8．A+BC= C 。
A .A+B B.A+C C.（A+B ）（A+C ） D.B+C9．在何种输入情况下，“与非”运算的结果是逻辑0。
DA ．全部输入是0 B.任一输入是0 C.仅一输入是0 D.全部输入是110．在何种输入情况下，“或非”运算的结果是逻辑1。
AA ．全部输入是0 B.全部输入是1 C.任一输入为0，其他输入为1 D.任一输入为111．十进制数25用8421BCD 码表示为 B 。
A .10 101B .0010 0101C .100101D .1010112．不与十进制数（53.5）10等值的数或代码为 C 。
A .(0101 0011.0101)8421BCDB .(35.8)16C .(110101.11)2D .(65.4)813．以下参数不是矩形脉冲信号的参数 D 。
A.周期B.占空比C.脉宽D.扫描期14．与八进制数(47.3)8等值的数为： BA. (100111.0101)2B.(27.6)16C.(27.3 )16D. (100111.101)215. 常用的BCD码有 D 。
数字电路与系统设计课后习题答案之欧阳理创编
1.1将下列各式写成按权展开式：（352.6）10=3×102+5×101+2×100+6×10-1（101.101）2=1×22+1×20+1×2-1+1×2-3（54.6）8=5×81+54×80+6×8-1（13A.4F）16=1×162+3×161+10×160+4×16-1+15×16-2 1.2按十进制0~17的次序，列表填写出相应的二进制、八进制、十六进制数。
解：略1.3二进制数00000000~11111111和0000000000~1111111111分别可以代表多少个数？解：分别代表28=256和210=1024个数。
1.4 将下列个数分别转换成十进制数：（1111101000）2，（1750）8，（3E8）16解：（1111101000）2=（1000）10（1750）8=（1000）10（3E8）16=（1000）101.5将下列各数分别转换为二进制数：（210）8，（136）10，（88）16解：结果都为：（10001000）21.6 将下列个数分别转换成八进制数：（111111）2，（63）10，（3F）16解：结果都为（77）81.7 将下列个数分别转换成十六进制数：（11111111）2，（377）8，（255）10解：结果都为（FF）161.8 转换下列各数，要求转换后保持原精度：解：（1.125）10=（1.0010000000）10——小数点后至少取10位（0010 1011 0010）2421BCD=（11111100）2（0110.1010）余3循环BCD码=（1.1110）21.9 用下列代码表示（123）10，（1011.01）2：解：（1）8421BCD码：（123）10=（0001 0010 0011）8421BCD（1011.01）2=（11.25）10=（0001 0001.0010 0101）8421BCD（2）余3 BCD码（123）10=（0100 0101 0110）余3BCD（1011.01）2=（11.25）10=（0100 0100.0101 1000）余3BCD1.10 已知A=（1011010）2，B=（101111）2，C=（1010100）2，D=（110）2（1）按二进制运算规律求A+B，A-B，C×D，C÷D，（2）将A、B、C、D转换成十进制数后，求A+B，A-B，C×D，C÷D，并将结果与（1）进行比较。
数字集成电路设计与系统分析答案
懂得1、Please illustrate the meaning of its voltage transfer characteristic to a logic gate, and describe the static behaviors showed in the voltage transfer characteristic curves.The electrical function of a gate is best expressed by its voltage transfer characteristic (VTC),which plots the output voltage as a function of the input voltage Vout=f(Vin).The high and low nominal voltage Voh and Vol;The gate or switching threshold voltage Vm,that is define as Vm=f(Vm)(The gate threshold voltage presents the midpoint of the switching characteristics,which is obtained when the output of a gate is short circuited to the input);The high and low input voltage Vih and Vil are defined by the point where the gain (=dVout/dVin)of the VTC equals -12、Please draw the voltage transfer characteristic curve of the inverter and label the static operation points in the VTC.3、Please describe the definition of noise margin and its physical significance(物理意义), then draw the figure of definition of noise margins.The noise margins represent the levels of noise that can be sustained(所允许的) when gates are cascaded. A measure of the sensitivity of a gate to noise is given by the noise margins NML(noise margin low) and NMH(noise margin high), which quantize the size of the legal “0” and “1”, respectively, and set a fixed maximum threshold on the noise value4、Please describe the meaning of the regenerative property and the conditions of a gate with regenerative property.A gate with regenerative property ensures that a disturbed signal converges back to a nominal voltage level after passing through a number of logical stages. The VTC should have a transient region (or undefined region) with a gain greater than 1 in absolute value, bordered by the two legal zones, where the gain should be less than 1 in absolute value5、What are the definitions of the fan-out and fan-in properties?The number that can be driven is termed the fan-out of circuit, that denotes the number of load gates N that are connected to the output of the driving gate. The fan-in of a gate is defined as the number of independent input nodes to the gate.6、How to describe the performance of a digital IC? Please illustrate the parameters used to characterize the transient performance of a logic family, and draw the associated figure of the definition of these parP ropagation delay time and rise/fall time can be used to characterize the transient performance of a logic family .Propagation delay time of a gate expresses the delay experienced by a signal when passing through a gate,which represent how quickly the gate responds to the changes at its inputs.Rise/fall time express how fast a signal transits between the different levels. Propagation delay time is defined as the period between the 50%transition points of the input and output signals.Rise/fall time is defined as the period between the 10% and 90% points of the total voltage transition at the output waveforms.1、Illustrate the basic structure and simple operation principle of MOS transistor.Four terminals:source, drain, gate, body; Vertical Structure: gate electrode, insulator, semiconductor substrate; Horizontal Structure: source region, channel region, drain region2、Illustrate the basic function of each terminal of MOS device, and describe the general terminal connections of NMOS and PMOS transistor, respectively.The source and the drain are the electrodes conducting the current. The gate electrode is thecontrolling terminal. The function of the body is secondaryIn NMOS devices, the source is defined as the n+ region which has a lower potential(电势) than the other n+ region, the drain. The source is the terminal with the higher potential in PMOS devices, The body is generally connected to a DC supply that is identical for all devices of the same type (GND for NMOS, VDD for PMOS).3、What does the transition (or input) characteristic of MOS transistor mean? And what conclusions we can find from the characteristic curve?It describes the relationship between the gate-source voltage and the drain-source current with the certain drain-source voltage .When the gate-source voltage is less than the threshold voltage, the conducting current is zero, that is, the NMOS transistor is in cutoff operation. When is larger than, the NMOS transistor is on.4、What does the current-voltage (or output) characteristic of MOS transistor mean? And what conclusions we can find from the I-V characteristic curve?.It describes the relationship between the drain-source voltage and the drain-source current with a certain gate-source voltageVgs > Vt , 0<VDS <VGS -VT : Linear modeThe inversion layer forms a continuous current path between the source and the drain.A drain current proportional to Vds will flow from the drain to the source through the conducting channel. The channel region acts as a voltage-controlled linear resister.5、Describe the operation modes of NMOS and PMOS transistors respectively, and define the corresponding ideal current equations.1、Explain the channel-length modulation, sub-threshold conduction, short-channel effect and narrow-channel effect. And illustrate their corresponding chief impacts on the device.This simple current equation prescribes a linear drain-bias dependence for the current in MOS transistors, determined by the empirical model parameter λ, called the channel-length modulation coefficientOne typical condition, which is due to the two-dimensional nature of channel current flow, is the sub-threshold conduction in small-geometry MOS transistors.As a working definition, a MOS transistor is called a short-channel device if its channel length is on the same order of magnitude as the depletion region thicknesses of the source and drain junctions.The short-channel effects that arise in this case are attributed to two physical phenomena: the limitations imposed on electron drift characteristics in the channel; the modification of the threshold voltage due to the shortening channel lengthMOS transistor that have channel widths on the same order of magnitude as the maxium depletion region thickness are defined as narrow channel devices.For MOSFET with small channel widths,the actual threshold voltage increases as a result of this extra depletion charge of the fringe depletion region.This fact is called narrow channel effect.2、Describe the three main components of the load capacitanceCL, when a logic gate is driving other fan-out gates. And sketch the capacitance model of NMOS transistor.Gate capacitances (of other inputs connected to out)Diffusion(or junction) capacitances (of drain/source regions)Routing capacitances (output to other inputs)1,Describe the basic structure and operation of a static CMOS inverter. Then draw theassociated transistor schematicThis structure consists of an enhancement-type NMOS transistor and an enhancement-type PMOS transistor, operating in complementary mode. So this configuration is called Complementary MOS (CMOS). The gate terminals of the PMOS and NMOS transistors are connected to form the inverter input. The drain terminals of the PMOS and NMOS transistors are connected to form the inverter output. The source and the substrate of the NMOS transistor are connected to the ground, while the source and body of PMOS transistor are connected to VDD The circuit topology is complementary push-pull in the sense that: For high input the NMOS transistor drives (pulls down) the output node while the PMOS transistor acts as the load, and for low input the PMOS transistor drives (pulls up) the output node while the NMOS transistor acts as the load.When the input is at VDD: The NMOS is on (conducting) while the PMOS is off (cut-off). A direct path exists between Vout and the ground node, resulting in a steady-state value of 0V at the output. When the input is at ground:The NMOS is off while the PMOS is on. A direct path exists between VDD and Vout, yielding a high output voltage (equal to VDD).Static CMOS logic:structure:The static CMOS style is really an extension of the static CMOS inverter to multiple inputs. A logic function in static CMOS must be implemented in both NMOS and PMOS transistors. It is the combination of the pull-up network(PUN) and the pull-down network(PDN). Each input always connects to PUN and PDN simultaneously. The function of the PUN is to provide a connection between the output and VDD anytime the output of the logic gate is meant to be 1 (based on the inputs). The function of the PDN is to connect the output to VSS when the output of the logic gate is meant to be 0.Opreation: The pull-down net should be “on” when the pull-up net is “off” and vice versa. For any given input combination, the output is connected either to VDD or to ground via a low-resistance path. A DC current path between the VDD and ground is not established for any of the input combinations. With the complementary nature of NMOS and PMOS, the pull-up or the pull-down is “on” alternately to implement the logic operation.Discuss the main problems for high fan-in static CMOS gates and the associated techniques for fast complex gates.tpHL = 0.69 Reqn(C1+2C2+3C3+4CL); Propagation delay deteriorates(恶化) rapidly as a function of fan-in quadratically in the worst case, Gates with a fan-in greater than 4 become excessively slow and must be avoided.tPLH increases linearly due to the linearly increasing value of the diffusion capacitance;tPHL increase quadratically due to the simultaneous increase the resistance and internal capacitance in serial part.Transistor sizing: as long as fan-out capacitance dominatesProgressive transistor sizing: This approach reduces the dominant resistance, while keeping the increase in capacitance within boundsTransfer gate:Configuration:The source and drain nodes serve as inputs and outputs, while the gate node serves as the control input, the body node is connected to the power/ground Operation: For NMOS transfer gate,it turns on while the gate control terminal goes high, and the input signal will be delivered to the output node; it turns off while the gate control terminal goes low, and the output node will be impedance.CMOS transmission gate:Configuration: The CMOS transmission gate consists of one NMOS and one PMOS transistor, with the source and drain connected in parallel; The gate voltages appliedto these two transistors are also set to be complementary signals. The substrate terminal of the NMOS transistor is connected to ground and the substrate terminal of the PMOS transistor is connected to Vdd.Operation: If the control signal C is logic-high (equal to Vdd), then both transistors are turned on and provide a low-resistance current path between the input and output nodes. If the control signal C is logic-low, then both transistors will be off, and the path between the input and output nodes will be in the high-impedance state. The weakness of one device is overcome by the strength of the other device, whether the output is transmitting a high or low value. This is a clear advantage of the CMOS transfer gate over the single transistor counterpart.DCVLS:Operation: Assume now that, for a given set of inputs, PDN1 conducts while PDN2 does not, and that Out and out are initially high and low, respectively. Turning on PDN1: Causes Out to be pulled down (below VDD−|VTP |); Out is in a high impedance state, as M2 and PDN2 are both turned off. At the point M2 turns on and starts charging out非to VDD — eventually turning off M1; This in turn enables Out to discharge all the way to GND.XOR/XNOR: When the signals A and B have the same values, there is one conducting path either AB or A非B非; Then the output F is pulled down;At the same time, the other pull-down paths connected to the F非are both turned off. When F is pulled down below VDD−|VTP |, M2 t urns on and starts charging F非to VDD —eventually turning off M1 and pulling down F to Gnd. When the signals A and B have the different values, there is one conducting path either AB非or A非B; Then the output F非is pulled down; At the same time, the other pull-down paths connected to the F are both turned off. When F非is pulled down below VDD−|VTP |, M1 turns on and starts charging F to VDD —eventually turning off M2 and pulling down F非to Gnd.Precharge-Evaluate dynamic CMOS:Operation: Precharge (when the clock signal Φ= 0)：The PMOS precharge transistor MP is conducting while the complementary NMOS transistor MN is off. The output load capacitance is precharged to VDD by MP, then VOH=VDD；The input voltages have no influence yet upon the output level since the complementary NMOS transistor MN is off. Evaluate (when the clock signal Φ=1)：The precharge transistor MP turns off while the NMOS evaluate transistor MN turns on. The output node voltage may now remain at the logic-high level or drop to a logic low, depending on the input voltage levels: If the input signals create a conducting path between the output node and the ground, PDN is on, and the output capacitance will discharge toward VOL=0;Otherwise, when PDN is off, the output voltage remains at VOH= VDD.Domino dynamic CMOS logic:When Φ=0, during precharge: The output of the n-type dynamic gate is charged up to VDD, and the output of the inverter is set to 0. When Φ=1, during evaluation: The dynamic gate conditionally discharges, and there are two possibilities: The output node of the dynamic CMOS stage is either discharged to a low level through the NMOS circuitry (1 to 0 transition), or it remains high. Consequently, the inverter output voltage can also make at most one transition during the evaluation phase, from 0 to 1.TSPC dynamic CMOS logic:Configuration:If one constrains a NORA stage to have only n-precharge gates, and not static gates, then a p-channel transistor can be eliminated from the clocked latch; The dynamic circuit technique to be presented in that it uses only one-phase clock signal, so no clock skew problem exists. The NORA design style can be simplified so that a single clock is sufficient. For the doubled n-C2MOS latch, when φ= 1, the latch is in the transparent evaluate mode and corresponds to 2 cascaded inverters (non-inverting); For the doubled n-C2MOS latch, when φ= 0, both inverters are disabled (hold mode) -- only the pull-up network is still active.Pipelined NORA dynamic CMOS system:Configuration: Consists of an np-CMOS logic sequence and a clocked CMOS output buffer; A pipelined system can be constructed by simply cascading alternating φ-section and φ -section, meaning that evaluation occurs during active φ and φ respectively;Operation:φ=0, during hold mode :N block performs the precharge operation and pulls node Out1 up to VDD through the p-type device Mp1, while p block performs the discharge operation and pulls the node Out2 down to zero through the n-type device Mn2; The clocked CMOS latch will not be in operation and the previous output voltage will be stored on the output load capacitor CL. φ=1, during evaluate mode:All cascaded NMOS and PMOS blocks evaluate output levels one after the other, and then the signal Out2 will be inversed to the output node by the clocked CMOS latch in operation;Operation Mode: Evaluate―Hold: All logic stages perform the precharge-discharge operation when the clock is high, and all stages evaluate output levels when the clock is low. Therefore, wewill call this circuit a section, meaning that evaluation occurs during active .Clocked CMOS dynamic circuit:Basic Structure:A pair of PMOS and NMOS transistors controlled by the complementary clock signals are cascaded in the pullup and pulldown paths of the static CMOS gate, respectively, then a CMOS logic gate can be synchronized with a clock. Operation: φ=1, during evaluation mode：The transistors Mp1 and Mp2 are both turned on, then this gate can evaluate normally as a CMOS inverter to generate the logic output In非; φ=0 , during hold mode: Both transistors Mp1 and Mp2 are off, decoupling the output from the input. The CMOS circuit cannot conduct and evaluate, then the output Q retains its previous value stored on the output capacitor CL.Sequential logic:Virtually all useful systems require storage of state information, leading to another class of circuits called sequential logic circuits. In these circuits, the output not only depends upon the current values of the inputs, but also upon preceding output values. In other words, a sequential circuit remembers some of the past history of the system; A sequential circuit consists of a combinational circuit and a memory block in the feedback loop.Combination logic:In all logic circuits described so far, the output is directly related to the input. Typically, there are no feedback loops between the output and the input in these circuits (also classified as non-regenerative circuits), so the outputs are always a logical combination of the inputs. As a class, these circuits are known as combinational logic circuits. Combinational logic circuits, described earlier, have the property that the output of a logic block is only a function of the current input values, assuming that enough time has elapsed for the logic gates to settle. Static storage:preserve state as long as the power is on;are built using positive feedback or regeneration with an intentional connection between the output and the input;useful when updates are infrequent (clock gating)Dynamic storage:store state on parasitic capacitors;only hold state for short periods of time (milliseconds);require periodic refresh to annihilate charge leakage;usually simpler, so higher speed and lower power;useful in datapath circuits that require high performance levels and are periodically clockedLatch: level sensitive circuit that passes inputs to Q when the clock is high (or low);input sampledon the falling edge of the clock is held stable when clock is low (or high)Register or Flip-flops (edge-triggered): edge sensitive circuits that only sample the inputs on a clock transitionpositive edge-triggered: 0- 1negative edge-triggered: 1 -0built using latches (e.g., master-slave flip-flops)。