Philips Semiconductors
Product specification
Hex inverting Schmitt trigger
DC CHARACTERISTICS FOR 74HCT
74HC/HCT14
For the DC characteristics see
“74HC/HCT/HCU/HCMOS Logic Family Specifications”.
Transfer characteristics are
given below.
Output capability: standard
I
CC
category: SSI
Note to HCT types
The value of additional quiescent supply current (∆I
CC
) for a unit load of 1 is given in the family specifications.
To determine
∆I
CC
per input, multiply this value by the unit load coefficient shown in the table below.
INPUT
nA
UNIT LOAD COEFFICIENT
0.3
Transfer characteristics for 74HCT
Voltages are referenced to GND (ground = 0 V)
T
amb
(°C)
74HCT
SYMBOL PARAMETER
+25
min.
V
T
+
V
T
−
V
H
positive-going
threshold
negative-going
threshold
hysteresis
(V
T
+
−V
T
−)
1.2
1.4
0.5
0.6
0.4
0.4
typ.
1.41
1.59
0.85
0.99
0.56
0.60
max.
1.9
2.1
1.2
1.4
−
−
−40
to +85
min.
1.2
1.4
0.5
0.6
0.4
0.4
max.
1.9
2.1
1.2
1.4
−
−
−40
to +125
min.
1.2
1.4
0.5
0.6
0.4
0.4
max.
1.9
2.1
1.2
1.4
−
−
V
V
V
4.5
5.5
4.5
5.5
4.5
5.5
Figs 6 and 7
Figs 6 and 7
Figs 6 and 7
UNIT
V
CC
WAVEFORMS
(V)
TEST CONDITIONS
AC CHARACTERISTICS FOR 74HCT
GND = 0 V; t
r
= t
f
= 6 ns; C
L
= 50 pF
T
amb
(°C)
74HCT
SYMBOL PARAMETER
+25
min.
t
PHL
/ t
PLH
t
THL
/ t
TLH
propagation delay
nA, to nY
output transition
time
typ.
20
7
max.
34
15
−40
to +85
min.
max.
43
19
−40
to +125
min.
max.
51
22
ns
ns
4.5
4.5
Fig.8
Fig.8
UNIT
V
CC
(V)
WAVEFORMS
TEST CONDITIONS
September 1993
5