第 3 章 组合逻辑电路
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数数数数数数 第 3 第 第第第第第第 数 数 3 3 数 数数数数数数 数 数数数数数数 3.1 第第 3.2 第第第第第第第第第第第第第第第第 3.3 第第第第第第第第第第第 数 数 数 数 数 数 数 数 数 数
description
第 3 章 组合逻辑电路. 第 3 章 组合逻辑电路. 3.1 概述 3.2 组合逻辑电路的分析方法和设计方法 3.3 若干常用的组合逻辑电路. 返 回 主 目 录. 第 3 章 组合逻辑电路. 3.1 概 述. 组合逻辑电路. 数字逻辑电路按逻辑功能分为. 时序逻辑电路. 一、组合逻辑电路的特点 功能特点：任一时刻的输出仅仅取决于该时刻的输入，而与 电路原来的状态无关。 结构特点：由门构成，不包含存储单元。. …. …. …. - PowerPoint PPT Presentation
Transcript of 第 3 章 组合逻辑电路
1
…
…
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.
.
DCBA 6
10 Y 1 = 1
DCBA
4
10 Z
0 1
= RAG + RA + RG + AG
= RAG RA RG AG
2
=1
=1
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
=
+ I0 I1 + I2 I1 + I3 I1 + I4 I1 + I5 I1 + I6 I1 + I7 I1
I0 I2 I3 I4 I5 I6 I7
= I1(
I0
I1
I2
I3
I4
I5
I6
I7
Y2
Y1
Y0
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
I4
I2
I3
I5
I7
I6
I1
Y2
Y1
Y0
≥1
≥1
≥1
n
1
2
0
1
0
1
0
0
1
1
0
× × ×
1 1 1 1 1 1 1 1
S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
1
1
1
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0
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S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
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S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
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S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
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1
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S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
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S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
1
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1
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1
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0
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1
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1
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1
S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
1
1
1
1
1
1
0
0
0
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0
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0
0
0
1
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S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
1
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0
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1
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1
1
1
1
1
1
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1
S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
1
1
1
1
1
1
0
0
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0
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1
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1
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1
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1
1
0
1
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1
1
1
1
1
1
0
1
1
1
1
1
1
1
1
0
1
1
1
1
1
1
1
1
0
1
1
1
1
1
1
1
1
0
S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
1
0
1
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0
1
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0
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1
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1
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1
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1
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1
1
1
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1
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1
1
1
1
1
1
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1
0
1
1
1
1
1
1
1
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0
1
1
1
1
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1
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1
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1
1
1
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S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
Y i = m i
[] 2 3 — 8 74LS138 4 — 16
4 D3 D2 D1 D0 16
D3
+5V
D2
D1
D0
4
S2 = S3 = 0;
.
.
.
.
.
.
3—874LS138
m0 ~ m7
S2 = S3 = 0
S2 = S3 = 0
S2 = S3 = 0
S2 = S3 = 0
S2 = S3 = 0
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y0
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y1
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y2
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y3
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y4
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y5
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y6
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y7
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y8
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y9
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
BCD0000 ~ 10011010~1111
101
BCD
m i A 3A 2A 1A 0 4
YaYb Yc Yd Yf Yg
10
S = 1
S = 0
S
41
A1
A0
Y
S = 1
S = 0
S
41
A1
A0
Y
1
2
A2A1A0
A2A1A0
A2A1A0
41
41
= RA G + RA G + RA G + RA (G + G )
.
.
.
.
.
.
.
.
A2 = A A1 = B A0 = C
Z = ABC + AC + ABC
Z = ABC + AC + ABC
= ABC + ABC+ ABC + ABC
.
.
.
.
A
B
C
S
A0
A1
D0
D1
D2
D3
Y
1
S
A0
A1
D0
D1
D2
D3
Y
S
A0
A1
D0
D1
D2
D3
Y
= ABC +ABC +ABC +ABC
= ABC +ABC +ABC +ABC
= BC 0 + BC 0 + BC 0 + BC D
.
.
.
.
= BC 0 + BC D + BC D + BC 1
.
.
.
.
= A1 0 D0+A10 D1+A1 0 D2+A10 D3
= A1 D0 + A1D2
= A1 0 D0+A10 D1+A1 0 D2+A10 D3
= A1 D0 + A1D2
= BC 0 + BC 0 + BC 0 + BC D
.
.
.
.
= BC 0 + BC D + BC D + BC 1
.
.
.
.
= A1 0 D0+A10 D1+A1 0 D2+A10 D3
= A1 D0 + A1D2
110
2 1
0101
0011
0101
0011
S — CO —
0
1
0
1
0
1
0
1
0
0
1
1
0
0
1
1
0
0
0
0
1
1
1
1
0
0
1
0
1
0
0
1
1
0
0
1
0
1
1
1
CI
AB
00
01
11
10
0
1
S
CI
AB
00
01
11
10
0
1
CO
_
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_
_
_
_
_
_
_
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…
…
…
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.
.
DCBA 6
10 Y 1 = 1
DCBA
4
10 Z
0 1
= RAG + RA + RG + AG
= RAG RA RG AG
2
=1
=1
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
=
+ I0 I1 + I2 I1 + I3 I1 + I4 I1 + I5 I1 + I6 I1 + I7 I1
I0 I2 I3 I4 I5 I6 I7
= I1(
I0
I1
I2
I3
I4
I5
I6
I7
Y2
Y1
Y0
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1
I4
I2
I3
I5
I7
I6
I1
Y2
Y1
Y0
≥1
≥1
≥1
n
1
2
0
1
0
1
0
0
1
1
0
× × ×
1 1 1 1 1 1 1 1
S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
1
0
1
0
1
0
1
0
0
1
1
0
0
1
1
0
0
0
0
1
1
1
1
S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
1
0
1
0
1
0
1
0
0
1
1
0
0
1
1
0
0
0
0
1
1
1
1
0
1
1
1
1
1
1
1
S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
1
0
1
0
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0
1
0
0
1
1
0
0
1
1
0
0
0
0
1
1
1
1
0
1
1
1
1
1
1
1
1
0
1
1
1
1
1
1
S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
1
0
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0
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1
1
1
1
1
1
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1
1
1
1
1
S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
1
1
1
1
1
1
0
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1
1
0
1
1
1
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S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
1
1
1
1
1
1
0
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0
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0
0
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0
1
0
1
0
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1
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1
1
1
1
1
1
1
1
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1
1
1
1
1
1
1
1
0
1
1
1
1
1
1
1
1
0
1
1
1
S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
1
1
1
1
1
1
0
0
0
0
0
0
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0
1
0
1
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1
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1
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1
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1
1
1
1
1
1
0
1
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S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
1
1
1
1
1
1
0
0
0
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0
1
0
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S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
1
1
1
1
1
1
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0
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1
1
1
1
0
1
1
1
1
1
1
1
1
0
1
1
1
1
1
1
1
1
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S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
× × ×
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
1
0
1
0
1
0
1
0
0
1
1
0
0
1
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0
0
0
1
1
1
1
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1
1
1
1
1
1
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1
1
1
1
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1
1
1
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1
1
1
1
1
1
1
1
0
1
1
1
1
1
1
1
1
0
1
1
1
1
1
1
1
1
0
1
1
1
1
1
1
1
1
0
1
1
1
1
1
1
1
1
0
S1 S2 + S3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7
3—874LS138
Y i = m i
[] 2 3 — 8 74LS138 4 — 16
4 D3 D2 D1 D0 16
D3
+5V
D2
D1
D0
4
S2 = S3 = 0;
.
.
.
.
.
.
3—874LS138
m0 ~ m7
S2 = S3 = 0
S2 = S3 = 0
S2 = S3 = 0
S2 = S3 = 0
S2 = S3 = 0
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y0
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y1
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y2
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y3
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y4
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y5
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y6
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y7
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y8
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
Y9
A3 A2 A1 A0 Y0 Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9
BCD0000 ~ 10011010~1111
101
BCD
m i A 3A 2A 1A 0 4
YaYb Yc Yd Yf Yg
10
S = 1
S = 0
S
41
A1
A0
Y
S = 1
S = 0
S
41
A1
A0
Y
1
2
A2A1A0
A2A1A0
A2A1A0
41
41
= RA G + RA G + RA G + RA (G + G )
.
.
.
.
.
.
.
.
A2 = A A1 = B A0 = C
Z = ABC + AC + ABC
Z = ABC + AC + ABC
= ABC + ABC+ ABC + ABC
.
.
.
.
A
B
C
S
A0
A1
D0
D1
D2
D3
Y
1
S
A0
A1
D0
D1
D2
D3
Y
S
A0
A1
D0
D1
D2
D3
Y
= ABC +ABC +ABC +ABC
= ABC +ABC +ABC +ABC
= BC 0 + BC 0 + BC 0 + BC D
.
.
.
.
= BC 0 + BC D + BC D + BC 1
.
.
.
.
= A1 0 D0+A10 D1+A1 0 D2+A10 D3
= A1 D0 + A1D2
= A1 0 D0+A10 D1+A1 0 D2+A10 D3
= A1 D0 + A1D2
= BC 0 + BC 0 + BC 0 + BC D
.
.
.
.
= BC 0 + BC D + BC D + BC 1
.
.
.
.
= A1 0 D0+A10 D1+A1 0 D2+A10 D3
= A1 D0 + A1D2
110
2 1
0101
0011
0101
0011
S — CO —
0
1
0
1
0
1
0
1
0
0
1
1
0
0
1
1
0
0
0
0
1
1
1
1
0
0
1
0
1
0
0
1
1
0
0
1
0
1
1
1
CI
AB
00
01
11
10
0
1
S
CI
AB
00
01
11
10
0
1
CO
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
_
