Datasheet

December 1990 3
Philips Semiconductors Product specification
Presettable synchronous 4-bit binary
up/down counter
74HC/HCT191
QUICK REFERENCE DATA
GND = 0 V; T
amb
=25°C; t
r
=t
f
=6ns
Notes
1. C
PD
is used to determine the dynamic power dissipation (P
D
in µW):
P
D
=C
PD
× V
CC
2
× f
i
+∑ (C
L
× V
CC
2
× f
o
) where:
f
i
= input frequency in MHz
f
o
= output frequency in MHz
∑ (C
L
× V
CC
2
× f
o
) = sum of outputs
C
L
= output load capacitance in pF
V
CC
= supply voltage in V
2. For HC the condition is V
I
= GND to V
CC
For HCT the condition is V
I
= GND to V
CC
−1.5 V
ORDERING INFORMATION
See
“74HC/HCT/HCU/HCMOS Logic Package Information” .
SYMBOL PARAMETER CONDITIONS
TYPICAL
UNIT
HC HCT
t
PHL
/ t
PLH
propagation delay CP to Q
n
C
L
= 15 pF; V
CC
= 5 V 22 22 ns
f
max
maximum clock frequency 36 36 MHz
C
I
input capacitance 3.5 3.5 pF
C
PD
power dissipation capacitance per package notes 1 and 2 31 33 pF