December 1990 7
Philips Semiconductors Product specification
4-bit magnitude comparator 74HC/HCT85
DC CHARACTERISTICS FOR 74HCT
For the DC characteristics see
“74HC/HCT/HCU/HCMOS Logic Family Specifications”
.
Output capability: standard
I
CC
category: MSI
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.
AC CHARACTERISTICS FOR 74HCT
GND = 0 V; t
r
=t
f
= 6 ns; C
L
= 50 pF
INPUT UNIT LOAD COEFFICIENT
I
A<B
I
A>B
I
A=B
A
n
, B
n
1.00
1.00
1.50
1.50
SYMBOL PARAMETER
T
amb
(°C) TEST CONDITIONS
74HCT
UNIT
V
CC
(V)
WAVEFORMS+25 −40 to +85 −40 to +125
min. typ. max. min. max. min. max.
t
PHL
/ t
PLH
propagation delay
A
n
, B
n
to Q
A>B
or Q
A<B
26 44 55 66 ns 4.5 Fig.6
t
PHL
/ t
PLH
propagation delay
A
n
, B
n
to Q
A=B
24 40 50 60 ns 4.5 Fig.6
t
PHL
/ t
PLH
propagation delay
I
A<B
, I
A=B
, I
A>B
to
Q
A<B
, Q
A>B
18 31 39 47 ns 4.5 Fig.6
t
PHL
/ t
PLH
propagation delay
I
A=B
to Q
A=B
18 31 39 47 ns 4.5 Fig.6
t
THL
/ t
TLH
output transition time 7 15 19 22 ns 4.5 Fig.6
