1
1
bvDè0y?" ù?
7.4
êè
^
V(+5V)
R
Y
A
B
C
D
1
D
2
D
3
0V
5V
-V(0V)
R
Y
A
B
C
D
1
D
2
D
3
0V
5V
7.4.1 =5?￥e?

ê
?
tc

o?￥á
3D) ?è
^
2
bvDè0y?" ù?
(1) F?
B T
1
aR
1

{ ?)
T
1
?
oDp
= T
2
aR
2
aT
6
aR
3
aR
6

?W)
T
2
bvasM
? T
3
aT
4
aT
5
aR
4
aR
5
w?
{)
T
3
è
üM?
7.4.2 TTLDd
ê
7.4.2.1 TTLDd
ê￥yTe ?
A
B
C
T
1
R
1
R
2
T
2
T
3
T
4
T
5
R
4
R
3
R
6
R
5
T
6
V
CC
(+5V)
Y
(v
0
)
(2) A" B" C" 1 (3.6V)
H
T
1
,Jc,T
2
,Je,T
5
,Je √
V
B5
=0.7V,V
B2
=1.4V,V
B1
=2.1V
T
1
,Je ×∴T
1
??bv
á
 i
B1
=(V
CC
-V
B1
)/R
1
≈1mA
∴ T
2
 v
C2
≈ 1V
∴ T
3
√ v
E3
≈ 0.3V
T
2
4@￥ i
B5
,∴ T
5

v
O
= 0.3V,∴ T
4
×, O V
BE4
= 0V
T
6

R3=300,R6=200)
∴ Y=V
L
=0
?
tc -7.4
êè
^
2
3
bvDè0y?" ù?
(3)
{ ?à
μB?1?
H
! A" 0 (0.3V);
B=C=1 (3.6V)
V
B1
=1V ∴ T
2 a
T
5a
T
6
×
a1 T
1
"è C¤ Rc→∞
∴ T
1
'
-
{ R
2
a?
V
E3
≈ V
CC
-V
BE3
= 4.3V
v
O
= V
E3
-V
BE4
= 3.6V
∴ Y= 1 (3.6V)
∴
A
B
C
T
1
R
1
R
2
T
2
T
3
T
4
T
5
R
4
R
3
R
6
R
5
T
6
V
CC
(+5V)
Y
(v
0
)
CBAY =
?
tc -7.4 7.4.2 TTLDd
ê
7.4.2.1 TTLDd
ê￥yTe ?
?
4
bvDè0y?" ù?
v
I
v
O
t
pHL
t
pLH
50%
50%
7.4.2.2 TTLDd
ê+?D?
2
pLHpHL
pd
tt
t
+
=
1 ?
+?

(1)
ü (.
{üt
HW t
pd
?
tc -7.4 7.4.2 TTLDd
ê
3
5
bvDè0y?" ù?
xx = wx =0
?85 (BJT) 71+?
v
O
T
R
B
v
I
R
C
V
CC
+
_
+
_
i
c
E (N)
B (P)
C (N)
Je Jc
?
?
è
é
Q
b
Q
bs
?? u
JeaJcQ
ê
bv u
Je?
êa JcQ
ê
i
C
=β i
B
 u
JeaJc?
ê
i
C
=I
CS
=(V
CC
-V
CES
)/ R
C
"?
v
BC
=0
I
CS
=β I
BS
BSB
Ii ≥

',
BS
B
I
i
N =
Nv

'
Q
bs
v
?
tc?85￥ 71+?
??
,


A
B
C
T
1
R
1
R
2
T
2
T
3
T
4
T
5
R
4
R
3
R
6
R
5
T
6
V
CC
(+5V)
Y
(v
0
)
(2) F
n
@,
A,¨ T
1
LCD
 
?
 T
1

B,?¨ T
4
aT
5
] ?5Tw?
{
?? ?ú
{ ?
B?
+?lM1?
T
1
???
á
3?v i
C1
=β
1
i
B1
?_bv
T
2
á
? ?
T
2
?? T
3a
T
4
?Y
i
C5
§W ↑ T
5
? ?
F y T
5
??
T
2 a
T
5
￥ t
S
↓↓ v
O
￥ t
r
↓
v
O
V? →ú T
5
×
a
T
4
√
i
O
=i
E4
R
O
l R
O
C
L
l t
r
↓
v
O
Vú →? T
4
×
a
T
5
√
i
O
= -i
C5
= βi
B5
v
C
L
bè y
t
f
↓
C
L
4
A
B
C
T
1
R
1
R
2
T
2
T
3
T
4
T
5
R
4
R
3
R
6
R
5
T
6
V
CC
(+5V)
Y
(v
0
)
C,T
6
aR
3
aR
6
F?s
@ F?
T
2
V?? →
?? R
3
￥i
i
E2
v?s? ? T
5

T
5
 y t
on
↓
]
H? T
6
a  i
E2
s
@
i
B5
↓
T
5
M 0
t
S
↓
T
2
V →??
T
5
￥ Q
bs
YV T
6
?b T
5
y
??
(1)
{úè
ü V
OH
T
5
×;T
4
√
?? 3.6V,V
OHmin
=2.4V
2 .
{+?
F? ?
?
A
B
C
T
1
R
1
R
2
T
2
T
3
T
4
T
5
R
4
R
3
R
6
R
5
T
6
V
CC
(+5V)
Y
(v
0
)
V
OH
V
OL
V
OLmax
V
OHmin
V
off
V
on
V
I
V
O
V
OLmax
V
OHmin
V
NL
V
NH
(2)
{?è
ü V
OL
T
5
√;T
4
×
?? 0.3V(Dμμ1
V
OLmax
=0.4V
(3)
{ ? 7
êè
ü V
ON
-? R
L
,
P V
O
=V
OLmax
H￥ V
I
=V
on
(4)
{ ?1
êè
ü V
OFF
-? R
L
,
P V
O
=V
OHmin
H￥ V
I
=V
off
(5) .
2 ?Kèa
V
NL
=V
off
-V
OLmax
----?è
ü.
2 ?Kèa
V
NH
=V
OHmin
-V
on
----úè
ü.
2 ?Kèa
5
z ? v
O
=V
OH
H ?è
@μ
i
O
= i
E4
i
E4
↑,R
4
a? ↑ V
OH
↓
z ? v
O
=V
OL
H9è
@μb
i
O
= - i
C5
i
C5
↑,??
@ i
C5
< β i
B5
H
T
5
? V
OL
↑
A
B
C
T
1
R
1
R
2
T
2
T
3
T
4
T
5
R
4
R
3
R
6
R
5
T
6
V
CC
(+5V)
Y
(v
0
)
3 μ+?
{μ
?
i
O
I
IL
0.3V
×
×
I
IH
3.6V
IHIL
II >>Q
5BILO
iIN β<∴
 ￡ V
OL

b T
5

' N
O
v
(1)
{ ??è
üè
@ I
IL
T1 -)￥9è
@μ (?v
(2)
{ ?úè
üè
@ I
IH
T1 -) ?è
@μ
?l
(3)
"
N
O

{
] ?
ê
10
bvDè0y?" ù?
4 ?{
(1) á
?{
(2) ?
?{
7.4.2.3 OC
êD ?
ê
1 OC
ê
open collector)
LCoLDp
7.4.2.2 TTLDd
ê+?D?

?
?
tc -7.4 7.4.2 TTLDd
ê
A
B
C
T
1
R
1
R
2
T
2
T
3
T
4
T
5
R
4
R
3
R
6
R
5
T
6
V
CC
(+5V)
Y
(v
0
)
2 ?
ê
�
9L2?
6
11
bvDè0y?" ù?
4 ?{
(1) á
?{
(2) ?
?{
7.4.2.3 OC
êD ?
ê
1 OC
ê
open collector)
LCoLDp
7.4.2.2 TTLDd
ê+?D?

?
?
tc -7.4 7.4.2 TTLDd
ê
A
B
C
T
1
R
1
R
2
T
2
T
3
T
4
T
5
R
4
R
3
R
6
R
5
T
6
V
CC
(+5V)
Y
(v
0
)
EN
2 ?
ê
�
9L2?
12
bvDè0y?" ù?
7.4.4 CMOS
êè
^
?
tc -7.4
êè
^
OD
ê
?
ê
7
13
bvDè0y?" ù?
7.4.4 CMOS
êè
^
?
?
tc -7.4
êè
^
+?
z F? ?
? <
z ?′èa? V
DD
/2
.
2 ?Kv
z è÷èaS? z
? ?{?
? μ
?
14
bvDè0y?" ù?
7.4.5
êè
^
P¨?￥ù5
1
êè
^
{
?
°¤
¤1è÷
2 TTL
ê￥
{ ?μ+?
V
OH
V
OL
V
OLmax
V
OHmin
V
off
V
on
V
I
V
O
V
OLmax
V
OHmin
V
NL
V
NH
1
êèE R
off
R<R
off
,5 v
O
=V
OH
7
êèE R
on
R>R
on
,5 v
O
=V
OL
3
ê￥?′èa V
th
TTL,V
th
≈1.4V
CMOS,V
th
≈V
DD
/ 2
A
B
C
T
1
R
1
R
2
T
2
T
3
T
4
T
5
R
4
R
3
R
6
R
5
T
6
V
CC
(+5V)
Y
(v
0
)
R
?
tc -7.4
êè
^