文档介绍：15-1 Basic Operational Characteristics
and Parameters.
15-2 CMOS Circuits
CH15 INTEGRATED CIRCUIT
TECHNOLOGIES
Chapter overview
15-3 TTL Circuits
15-4 Practical Considerations in the
Use of TTL.
15-parison of CMOS and TTL
Performance.
P
N
+ uD -
i-v characteristic
Switching circuit
Switching performance of a Diode
+
u
i
=0V
R
L
-
+
u
o
-
D
+ +
-
u
i
=5V
R
L
-
+
u
o
-
D
Equivalent
circuit
(1)DC Supply voltage :
TTL (transistor-transistor logic)
:+5V
CMOS (complementary medal oxide
semiconductor)
:+5V,+
15-1 Basic Operational Characteristics and Parameters
(2) Logic levels
VIL ,VIH,VOL,VOH.
The range of CMOS circuits:
VIL:0~ (for 5V CMOS)
VIL:0~ (for CMOS)
VIH:~5V (for 5V CMOS)
VIH:2~ (for CMOS)
Unallowed ranges:
~ or ~2V.
When the input voltages are in the unallowed ranges ,CMOS gates cannot be operated reliably.
Input Output
0V
LOW
( 0 )
HIGH
( 1 )
eptable
5V
VIH(min)
VIL(max)
0V
LOW( 0 )
HIGH( 1 )
eptable
5V
VOL(max)
VOH(min)
(a) +5V CMOS
Input Output
0V
2V
LOW
( 0 )
HIGH
( 1 )
eptable
VIH(min)
VIL(max)
0V
LOW( 0 )
HIGH( 1 )
eptable
VOL(max)
VOH(min)
(b) + CMOS
(3) Noise immunity
Noise :Unwanted voltage induced in
electrical circuits.
. :High frequency ic
radiation,
power-line voltage fluctuation.
Noise immunity: the ability to tolerate a certain amount of unwanted voltage fluctuation on its inputs without changing its output state.