HD74ALVCH16334
16-bit Universal Bus Driver with 3-state Outputs
ADE-205-212 (Z)
Preliminary
1st. Edition
December 1997
Description
This HD74ALVCH16334 is a 16-bit universal bus driver is designed for 2.3 V to 3.6 V V
CC
operation.
Data flow from A to Y is controlled by the output enable (O
E)
input. The device operates in the
transparent mode when the latch enable (LE) input is low. When
LE
is high, the A data is latched if the
clock (CLK) input is held at a high or low logic level. If
LE
is high, the A data is stored in the latch/flip
flop on the low to high transition of CLK. When
OE
is high, the outputs are in the high impedance state.
To ensure the high impedance state during power up or power down,
OE
should be tied to V
CC
through a
pullup resistor; the minimum value of the resistor is determined by the current sinking capability of the
driver.
Active bus hold circuitry is provided to hold unused or floating inputs at a valid logic level.
Features
•
V
CC
= 2.3 V to 3.6 V
•
Typical V
OL
ground bounce < 0.8 V (@V
CC
= 3.3 V, Ta = 25°C)
•
Typical V
OH
undershoot > 2.0 V (@V
CC
= 3.3 V, Ta = 25°C)
•
High output current ±24 mA (@V
CC
= 3.0 V)
•
Bus hold on data inputs eliminates the need for external pullup / pulldown resistors
HD74ALVCH16334
Function Table
Inputs
OE
H
L
L
L
L
L
LE
X
L
L
H
H
H
CLK
X
X
X
↑
↑
L or H
A
X
L
H
L
H
X
Z
L
H
L
H
Y
0
*1
Output Y
H : High level
L : Low level
X : Immaterial
Z : High impedance
↑
: Low to high transition
Note: 1. Output level before the indicated steady state input conditions were established.
2
HD74ALVCH16334
Pin Arrangement
OE
1
Y1 2
Y2 3
GND 4
Y3 5
Y4 6
V
CC
7
Y5 8
Y6 9
GND 10
Y7 11
Y8 12
Y9 13
Y10 14
GND 15
Y11 16
Y12 17
V
CC
18
Y13 19
Y14 20
GND 21
Y15 22
Y16 23
NC 24
48 CLK
47 A1
46 A2
45 GND
44 A3
43 A4
42 V
CC
41 A5
40 A6
39 GND
38 A7
37 A8
36 A9
35 A10
34 GND
33 A11
32 A12
31 V
CC
30 A13
29 A14
28 GND
27 A15
26 A16
25
LE
(Top view)
3
HD74ALVCH16334
Absolute Maximum Ratings
Item
Supply voltage
Input voltage
*1
Output voltage
*1, 2
Input clamp current
Output clamp current
Continuous output current
V
CC
, GND current / pin
Maximum power dissipation
at Ta = 55°C (in still air)
*3
Storage temperature
Notes:
Symbol
V
CC
V
I
V
O
I
IK
I
OK
I
O
I
CC
or I
GND
P
T
T
stg
Ratings
–0.5 to 4.6
–0.5 to 4.6
–0.5 to V
CC
+0.5
–50
±50
±50
±100
0.85
–65 to 150
Unit
V
V
V
mA
mA
mA
mA
W
°C
TSSOP
V
I
< 0
V
O
< 0 or V
O
> V
CC
V
O
= 0 to V
CC
Conditions
Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage
to the device. These are stress ratings only, and functional operation of the device at these or
any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute maximum rated conditions for extended periods may affect device
reliability.
1. The input and output negative voltage ratings may be exceeded if the input and output clamp
current ratings are observed.
2. This value is limited to 4.6 V maximum.
3. The maximum package power dissipation is calculated using a junction temperature of 150°C
and a board trace length of 750 mils.
Recommended Operating Conditions
Item
Supply voltage
Input voltage
Output voltage
High level output current
Symbol
V
CC
V
I
V
O
I
OH
Min
2.3
0
0
—
—
—
Low level output current
I
OL
—
—
—
Input transition rise or fall rate
Operating temperature
∆t
/
∆v
T
a
0
–40
Max
3.6
V
CC
V
CC
–12
–12
–24
12
12
24
10
85
ns / V
°C
mA
Unit
V
V
V
mA
V
CC
= 2.3 V
V
CC
= 2.7 V
V
CC
= 3.0 V
V
CC
= 2.3 V
V
CC
= 2.7 V
V
CC
= 3.0 V
Conditions
Note: Unused control inputs must be held high or low to prevent them from floating.
4
HD74ALVCH16334
Logic Diagram
OE
CLK
LE
A1
1
48
25
47
1D
C1
CLK
2
Y1
To fifteen other channels
5