TL F 7506
DS1648DS3648DS1678DS3678
TRI-STATE
TTL
to
MOS
MultiplexersDrivers
February 1986
DS1648 DS3648 DS1678 DS3678 TRI-STATE
TTL to
MOS Multiplexers Drivers
General Description
The DS1648 DS3648 and DS1678 DS3678 are quad 2-in-
put multiplexers with TRI-STATE outputs designed to drive
the large capacitive loads (up to 500 pF) associated with
MOS memory systems A PNP input structure is employed
to minimize input currents so that driver loading in large
memory systems is reduced The circuit employs Schottky-
clamped transistors for high speed and TRI-STATE outputs
for bus operation
The DS1648 DS3648 has a 15X resistor in series with the
outputs to dampen transients caused by the fast-switching
output The DS1678 DS3678 has a direct low impedance
output for use with or without an external resistor
Features
Y
TRI-STATE outputs interface directly with system-bus
Y
Schottky-clamped for better ac performance
Y
PNP inputs to minimize input loading
Y
TTL compatible
Y
High-speed capacitive load drivers
Y
Built-in damping resistor (DS1648 DS3648 only)
Logic and Connection Diagrams
TL F 7506 1
Dual-In-Line Package
TL F 7506 2
Top View
Order Number DS1648J DS3648J DS1678J
DS3678J DS3648N or DS3678N
See NS Package Number J16A or N16A
TRI-STATE
is a registered trademark of National Semiconductor Corp
C1995 National Semiconductor Corporation
RRD-B30M105 Printed in U S A
Absolute Maximum Ratings
(Note 1)
If Military Aerospace specified devices are required
please contact the National Semiconductor Sales
Office Distributors for availability and specifications
Supply Voltage
7V
Logical ``1'' Input Voltage
7V
Logical ``0'' Input Voltage
b
1 5V
Storage Temperature Range
b
65 C to
a
150 C
Maximum Power Dissipation at 25 C
Cavity Package
1433 mW
Molded Package
1362 mW
Lead Temperature
(Soldering 10 seconds)
300 C
Derate cavity package 9 6 mW C above 25 C derate molded package
10 9 mW C above 25 C
Operating Conditions
Min
Max
Units
Supply Voltage (V
CC
)
4 5
5 5
V
Temperature (T
A
)
DS1648 DS1678
b
55
a
125
C
DS3648 DS3678
0
a
70
C
Electrical Characteristics
(Notes 2 and 3)
Symbol
Parameter
Conditions
Min
Typ
Max
Units
V
IN(1)
Logical ``1'' Input Voltage
2 0
V
V
IN(0)
Logical ``0'' Input Voltage
0 8
V
I
IN(1)
Logical ``1'' Input Current
V
CC
e
5 5V V
IN
e
5 5V
0 1
40
m
A
I
IN(0)
Logical ``0'' Input Current
V
CC
e
5 5V V
IN
e
0 5V
b
50
b
250
m
A
V
CLAMP
Input Clamp Voltage
V
CC
e
4 5V I
IN
e b
18 mA
b
0 75
b
1 2
V
V
OH
Logical ``1'' Output Voltage
V
CC
e
4 5V I
OH
e b
10 mA
DS1648 DS1678
2 7
3 6
V
(No Load)
DS3648 DS3678
2 8
3 6
V
V
OL
Logical ``0'' Output Voltage
V
CC
e
4 5V I
OL
e
10 mA
DS1648 DS1678
0 25
0 4
V
(No Load)
DS3648 DS3678
0 25
0 35
V
V
OH
Logical ``1'' Output Voltage
V
CC
e
4 5V I
OH
e b
1 0 mA
DS1648
2 4
3 5
V
(With Load)
DS1678
2 5
3 5
V
DS3648
2 6
3 5
V
DS3678
2 7
3 5
V
V
OL
Logical ``0'' Output Voltage
V
CC
e
4 5V I
OL
e
20 mA
DS1648
0 6
1 1
V
(With Load)
DS1678
0 4
0 5
V
DS3648
0 6
1 0
V
DS3678
0 4
0 5
V
I
1D
Logical ``1'' Drive Current
V
CC
e
4 5V V
OUT
e
0V (Note 4)
b
250
mA
I
0D
Logical ``0'' Drive Current
V
CC
e
4 5V V
OUT
e
4 5V (Note 4)
150
mA
I
Hi-Z
TRI-STATE Output Current
V
OUT
e
0 4V to 2 4V Output Control
e
2 0V
b
40
40
m
A
I
CC
Power Supply Current
V
CC
e
5 5V
Output Control
e
3V
42
60
mA
All Other Inputs at 0V
All Inputs at 0V
20
32
mA
Note 1
``Absolute Maximum Ratings'' are those values beyond which the safety of the device cannot be guaranteed Except for ``Operating Temperature Range''
they are not meant to imply that the devices should be operated at these limits The table of ``Electrical Characteristics'' provides conditions for actual device
operation
Note 2
Unless otherwise specified min max limits apply across the
b
55 C to
a
125 C temperature range for the DS1648 and DS1678 and across the 0 C to
a
70 C range for the DS3648 and DS3678 All typical values for T
A
e
25 C and V
CC
e
5V
Note 3
All currents into device pins shown as positive out of device pins as negative all voltages referenced to ground unless otherwise noted All values shown
as max or min on absolute value basis
Note 4
When measuring output drive current and switching response for the DS1678 and DS3678 a 15X resistor should be placed in series with each output This
resistor is internal to the DS1648 DS3648 and need not be added
2
Switching Characteristics
V
CC
e
5V T
A
e
25 C (Note 4)
Symbol
Parameter
Conditions
Min
Typ
Max
Units
t
S
g
Storage Delay Negative Edge
(Figure 1)
C
L
e
50 pF
5
7
ns
C
L
e
500 pF
9
12
ns
t
S
'
Storage Delay Positive Edge
(Figure 1)
C
L
e
50 pF
6
8
ns
C
L
e
500 pF
9
13
ns
t
F
Fall Time
(Figure 1)
C
L
e
50 pF
5
8
ns
C
L
e
500 pF
22
35
ns
t
R
Rise Time
(Figure 1)
C
L
e
50 pF
6
9
ns
C
L
e
500 pF
22
35
ns
t
ZL
Delay from Output Control Input to Logical ``0''
C
L
e
50 pF R
L
e
2 kX to V
CC
10
15
ns
Level (from High Impedance State)
(Figure 2)
t
ZH
Delay from Output Control Input to Logical ``1''
C
L
e
50 pF R
L
e
2 kX to GND
8
15
ns
Level (from High Impedance State)
(Figure 2)
t
LZ
Delay from Output Control Input to High Impedance
C
L
e
50 pF R
L
e
400X to V
CC
15
25
ns
State (from Logical ``0'' Level)
(Figure 3)
t
HZ
Delay from Output Control Input to High Impedance
C
L
e
50 pF R
L
e
400X to GND
10
25
ns
State (from Logical ``1'' Level)
(Figure 3)
t
S
g
Propagation Delay to Logical ``0'' Transition When
C
L
e
50 pF
(Figure 1)
12
15
ns
Select Selects A
t
S
'
Propagation Delay to Logical ``1'' Transition When
C
L
e
50 pF
(Figure 1)
14
17
ns
Select Selects A
t
S
g
Propagation Delay to Logical ``0'' Transition When
C
L
e
50 pF
(Figure 1)
16
20
ns
Select Selects B
t
S
'
Propagation Delay to Logical ``1'' Transition When
C
L
e
50 pF
(Figure 1)
14
20
ns
Select Selects B
Schematic Diagram
TL F 7506 3
DS1648 DS3648 only
3
AC Test Circuits and Switching Time Waveforms
t
S
g
t
S
g
T
R
t
F
TL F 7506 4
TL F 7506 5
Note 1
The pulse generator has the following characteristics Z
OUT
e
50X and PRR
s
1 MHz Rise and fall times between 10% and 90% points
s
5 ns
Note 2
C
L
includes probe and jig capacitance
FIGURE 1
t
ZH
TL F 7506 6
Internal on DS1648 and DS3648
t
ZL
TL F 7506 7
TL F 7506 8
FIGURE 2
t
HZ
TL F 7506 9
Internal on DS1648 and DS3648
t
LZ
TL F 7506 10
TL F 7506 11
FIGURE 3
Truth Table
Output
Inputs
Outputs
Control
Select
A
B
H
X
X
X
Hi-Z
L
L
L
X
H
L
L
H
X
L
L
H
X
L
H
L
H
X
H
L
H
e
High level
L
e
Low level
X
e
Don't care
Hi-Z
e
TRI-STATE mode
4
Typical Applications
Addressing 16k RAM
TL F 7506 12
2 1 Multiplexing of RAM Outputs
TL F 7506 14
Refreshing Using TRI-STATE Counter
TL F 7506 13
5
PDF 
ZIP