HD74LV393A
Dual 4-bit Binary Counters
ADE-205-276 (Z)
1st Edition
April 1999
Description
The HD74LV393A contain two 4-bit ripple carry binary counters, which can be cascaded to create a single
divide-by-256 counter.
The HD74LV393A is incremented on the high to low transition (negative edge) of the clock input, and
each has an independent clear input. When clear is set high all four bits of each counter are set to a low
level. This enables count trucation and allows the implementation of divide-by-N counter configurations.
Low-voltage and high-speed operation is suitable for the battery-powered products (e.g., notebook
computers), and the low-power consumption extends the battery life.
Features
V
CC
= 2.0 V to 5.5 V operation
All inputs V
IH
(Max.) = 5.5 V (@V
CC
= 0 V to 5.5 V)
All outputs V
O
(Max.) = 5.5 V (@V
CC
= 0 V)
Typical V
OL
ground bounce < 0.8 V (@V
CC
= 3.3 V, Ta = 25
C)
Typical V
OH
undershoot > 2.3 V (@V
CC
= 3.3 V, Ta = 25
C)
Output current
6 mA (@V
CC
= 3.0 V to 3.6 V),
12 mA (@V
CC
= 4.5 V to 5.5 V)
HD74LV393A
3
Absolute Maximum Ratings
Item
Symbol
Ratings
Unit
Conditions
Supply voltage range
V
CC
0.5 to 7.0
V
Input voltage range*
1
V
I
0.5 to 7.0
V
Output voltage range*
1, 2
V
O
0.5 to V
CC
+ 0.5
V
Output: H or L
0.5 to 7.0
V
CC
: OFF
Input clamp current
I
IK
20
mA
V
I
< 0
Output clamp current
I
OK
50
mA
V
O
< 0 or V
O
> V
CC
Continuous output current
I
O
25
mA
V
O
= 0 to V
CC
Continuous current through
V
CC
or GND
I
CC
or I
GND
70
mA
Maximum power dissipation
at Ta = 25
C (in still air)*
3
P
T
785
mW
SOP
500
TSSOP
Storage temperature
Tstg
65 to 150
C
Notes: The absolute maximum ratings are values which must not individually be exceeded, and furthermore,
no two of which may be realized at the same time.
1. The input and output voltage ratings may be exceeded if the input and output clamp-current
ratings are observed.
2. This value is limited to 5.5 V maximum.
3. The maximum package power dissipation was calculated using a junction temperature of 150
C.
HD74LV393A
4
Recommended Operating Conditions
Item
Symbol
Min
Max
Unit
Conditions
Supply voltage range
V
CC
2.0
5.5
V
Input voltage range
V
I
0
5.5
V
Output voltage range
V
O
0
V
CC
V
H or L
Output current
I
OH
--
50
A
V
CC
= 2.0 V
--
2
mA
V
CC
= 2.3 to 2.7 V
--
6
V
CC
= 3.0 to 3.6 V
--
12
V
CC
= 4.5 to 5.5 V
I
OL
--
50
A
V
CC
= 2.0 V
--
2
mA
V
CC
= 2.3 to 2.7 V
--
6
V
CC
= 3.0 to 3.6 V
--
12
V
CC
= 4.5 to 5.5 V
Input transition rise or fall rate
t /
v
0
200
ns/V
V
CC
= 2.3 to 2.7 V
0
100
V
CC
= 3.0 to 3.6 V
0
20
V
CC
= 4.5 to 5.5 V
Operating free-air temperature
Ta
40
85
C
Note:
Unused or floating inputs must be held high or low.
Logic Diagram
CK
Q
R
QA
CK
Q
R
QB
CK
Q
R
QC
CK
Q
R
QD
CLK
CLR
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