数字电子技术基础_第四版_阎石_课后答案[1-6章]
- 格式:pdf
- 大小:1.78 MB
- 文档页数:28
(2)Y = A + C + D
(3)Y = (A + B)( A + C)AC + BC 解:Y = ( A + B)(A + C)AC + BC = [( A + B)( A + C) + AC]⋅ BC = ( AB + AC + BC + AC)(B + C) = B + C
(2)Y = ( A + B + C)( A + B + C)( A + B + C)
(3)Y = M 0 ⋅ M 3 ⋅ M 4 ⋅ M 6 ⋅ M 7
(4)Y = M 0 ⋅ M 4 ⋅ M 6 ⋅ M 9 ⋅ M12 ⋅ M13
(5)Y = M 0 ⋅ M 3 ⋅ M 5
1.13 用卡诺图化简法将下列函数化为最简与或形式: (1)Y = A + D (2)Y = AB + AC + BC + C D
0 (INH=1) (C) Y=
AB + CD (INH = 0)
2.18 (a) Ya = ABCDE
(b) Yb = A + B + C + D + E
(c) Yc = ABC + DEF
(d ) Yd = A + B + C • D + E + F
2.19 不能。会使低电平变高,高电平变低。 2.20 解:
= 0.05mA <
I
,
B
∴
T饱和,
v o=0.2V
(0
~
0.3V都行)
2.3 解:
s 闭合时,L ≤ 0.4V
R2
≤
0.4 5I I′L
=
0.4V 2mA
= 200Ω
s 断开时,输入为高电平,此时
R2的最大允许值为200Ω
VIH = Vcc − (R1 + R2 ) × 5I IH ≥ 4V ∴ R1最大允许值为10K-R 2
(4)Y = A + B + C
(5)Y = AD + AC + BCD + C 解:Y = (A + D)(A + C)(B + C + D)C = AC(A + D)(B + C + D) = ACD(B + C + D) = ABCD
1.11 将函数化简为最小项之和的形式
(6)Y = 0
(1)Y = ABC + AC + BC 解:Y = ABC + AC + BC = ABC + A(B + B )C + ( A + A)BC = ABC + ABC + ABC + ABC + ABC = ABC + ABC + ABC + ABC
=
− 10 5.1 + 20
× 5.1 =
−2V
∴T截止 vo ≈ 10V
当
v
i=5V时,
I
=
B
5-0.7 5.1
−
10.7 20
=
0.3mA
I BS
≈
10 30 × 2
= 0.17 mA <
IB
∴ T饱和
vo ≈ 0.2V (0 ~ 0.3V都行)
悬空时, v B负值, T截止, vo ≈ 10V
2
数字电路 习题答案 (第二章)
2.10 (1) vi2 = 1.4V (2) vi2 = 0.2V (3) vi2 = 1.4V (4) vi2 = 0.2V (5) vi2 = 1.4V
2.11 各种情况均为 1.4V 2.12 解:
输出为高电平时:Vo = Vcc − (0.2 × 2 − iL )RL = 4.6 + iL RL
(5)Y =1
2
Y = ABC + ABC + ABC
(2)Y = CD + ACD (4)Y = BC + B D
(2)Y = B + AD + AC (4)Y = A + B D (6)Y = CD + B D + AC
数字电路 习题答案 (第二章)
第二章
2.1 解:
(a)当v i=0V时, v B
⎪ ⎪
I 2 = I 3 + I BS
⎪⎭
∴ 1.1K ≤ R1 ≤ 4.46 K
2.9 解:
(1) 同上题解法:I LM = 16mA
I L = 5 ×1.4 = 7mA
⇒
Ic
=
I Rc
+
IL
=
Vcc − 0.3 Rc
+
IL
= 8mA
可解得:0.3K ≤ RB ≤ 33.1K
⇒ I BS
=
Ic β
I
OL (max) 2I IL
=
16 2 ×1.6
=
5
N
高=
I
OH (max) 2I IH
=
0.4 2 × 0.04
=
5
∴ 最多能驱动5个相同的或非门
2.7 解:根据公式:
R L (max)
=
Vcc − VOH nI OH + mI IH
= 5 − 3.2 = 5K 3× 0.1 + 3× 0.02
(9)Y = BC + AD + AD
1.9 (a) Y = ABC + BC
(10)Y = AC + AD + AEF + BDE + BDE (b) Y = ABC + ABC
(c) Y1 = AB + AC D,Y2 = AB + AC D + ACD + ACD
(d) Y1 = AB + AC + BC,Y2 = ABC + ABC + ABC + ABC 1.10 求下列函数的反函数并化简为最简与或式
(b)当v i=0V时, vB为负值 ∴ T截止 vo=5V
当
v
i=5V时,
I
=
B
5-0.7 54。7
−
8.7 18
=
0.42 mA
I BS
≈
5 50 × 2
= 0.05mA <
IB
∴ T饱和
vo ≈ 0.2V (0 ~ 0.3V都行)
悬空时,
I
=
B
5-0.7 4.7
−
8.7 18
=
0.08 mA
I BS
= 0.08mA
(2)把 OC 门换成 TTL 门时, 若门输出为低电平时两者相同,无影响; 但输出高电平时两者截然不同,OC 门向内流进(漏电流), 而 TTL 的电流是向外流出,IB=IRB+IOH ,IOH 为 TTL 输出高电平时的输出电流。 由输出特性曲线知:当 VOH 下降到 0.7V 时,IOH 相当大,IC 也很大,会烧毁三极管。
(1)Y=A+B
(3)Y=1
(2)Y = ABC + A + B +C 解:Y = BC + A + B +C =C + A + B +C =(1 A+A=1)
(5)Y=0
(4)Y = ABCD + ABD + ACD 解:Y = AD(BC + B + C ) = AD(B + C + C) = AD
(1)(17)10=(10001)2=(11)16
(3) (0.39)10 = (0.0110 0011 1101 0111 0000 1010)2 = (0.63 D70A )16
1.8 用公式化简逻辑函数
(2)(127)10=(1111111)2=(7F)16
(4) (25.7)10 = (11001.1011 0011)2 = (19.B3)16
(2)Y = ABCD + ABCD + ABCD + ABCD + ABCD + ABCD
1
数字电路 习题答案 (第一章)
(3)Y = A + B + CD 解:Y = A(BC D + BCD + BCD + BCD + BC D + BC D + BCD + BCD) + B(AC D + ACD + ACD + ACD + AC D + AC D + ACD + ACD) + (AB + AB + AB + AB)CD = ABC D + ABCD + ABCD + ABCD + ABC D + ABC D + ABCD + ABCD + ABC D + ABCD + ABCD + ABCD + ABCD (13)
(10)Y ( A, B, C) = ∑( m1,m4 , m7 )
Y = B + CD + AD 1.14 化简下列逻辑函数
(1)Y = A + B + C + D (3)Y = AB + D + AC (5)Y = AB + DE + CE + BDE + AD + ACDE