74VCX162373 Low Voltage 16-Bit Transparent Latch
January 2000
Revised June 2005
74VCX162373
Low Voltage 16-Bit Transparent Latch
with 3.6V Tolerant Inputs and Outputs
and 26: Series Resistors in Outputs
General Description
The VCX162373 contains sixteen non-inverting latches
with 3-STATE outputs and is intended for bus oriented
applications. The device is byte controlled. The flip-flops
appear to be transparent to the data when the Latch enable
(LE) is HIGH. When LE is LOW, the data that meets the
setup time is latched. Data appears on the bus when the
Output Enable (OE) is LOW. When OE is HIGH, the out-
puts are in a high impedance state.
The VCX162373 is also designed with 26
:
resistors in the
outputs. This design reduces line noise in applications
such as memory address drivers, clock drivers and bus
transceivers/transmitters.
The 74VCX162373 is designed for low voltage (1.4V to
3.6V) V
CC
applications with I/O compatibility up to 3.6V.
The 74VCX162373 is fabricated with an advanced CMOS
technology to achieve high speed operation while maintain-
ing low CMOS power dissipation.
Features
s
1.4V–3.6V V
CC
supply operation
s
3.6V tolerant inputs and outputs
s
26
:
series resistors in outputs
s
t
PD
(I
n
to O
n
)
3.3 ns max for 3.0V to 3.6V V
CC
s
Power-off high impedance inputs and outputs
s
Support live insertion and withdrawal (Note 1)
s
Static Drive (I
OH
/I
OL
)
r
12 mA @ 3.0V V
CC
s
Uses patented noise/EMI reduction circuitry
s
Latch-up performance exceeds 300 mA
s
ESD performance:
Human body model
!
2000V
Machine model
!
200V
Note 1:
To ensure the high-impedance state during power up or power
down, OE should be tied to V
CC
through a pull-up resistor; the minimum
value of the resistor is determined by the current-sourcing capability of the
driver.
Ordering Code:
Ordering Number
74VCX162373MTD
Package
Number
MTD48
Package Description
48-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 6.1mm Wide
Devices also available in Tape and Reel. Specify by appending suffix letter “X” to the ordering code.
Logic Symbol
Pin Descriptions
Pin Names
OE
n
LE
n
I
0
–I
15
O
0
–O
15
Description
Output Enable Input (Active LOW)
Latch Enable Input
Inputs
Outputs
© 2005 Fairchild Semiconductor Corporation
DS500236
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74VCX162373
Connection Diagram
Truth Tables
Inputs
LE
1
X
H
H
L
OE
1
H
L
L
L
Inputs
LE
2
X
H
H
L
H
L
X
Z
O
0
Outputs
I
0
–I
7
X
L
H
X
O
0
–O
7
Z
L
H
O
0
Outputs
I
8
–I
15
X
L
H
X
O
8
–O
15
Z
L
H
O
0
OE
2
H
L
L
L
HIGH Voltage Level
LOW Voltage Level
Immaterial (HIGH or LOW, inputs may not float)
High Impedance
Previous O
0
before HIGH-to-LOW of Latch Enable
Functional Description
The 74VCX162373 contains sixteen edge D-type latches
with 3-STATE outputs. The device is byte controlled with
each byte functioning identically, but independent of the
other. Control pins can be shorted together to obtain full
16-bit operation. The following description applies to each
byte. When the Latch Enable (LE
n
) input is HIGH, data on
the I
n
enters the latches. In this condition the latches are
transparent, i.e., a latch output will change state each time
its I input changes. When LE
n
is LOW, the latches store
information that was present on the I inputs a setup time
preceding the HIGH-to-LOW transition on LE
n
. The
3-STATE outputs are controlled by the Output Enable
(OE
n
) input. When OE
n
is LOW the standard outputs are in
the 2-state mode. When OE
n
is HIGH, the standard outputs
are in the high impedance mode but this does not interfere
with entering new data into the latches.
Logic Diagram
Please note that this diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays.
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2
74VCX162373
Absolute Maximum Ratings
(Note 2)
Supply Voltage (V
CC
)
DC Input Voltage (V
I
)
Output Voltage (V
O
)
Outputs 3-STATED
Outputs Active (Note 3)
DC Input Diode Current (I
IK
) V
I
0V
DC Output Diode Current (I
OK
)
V
O
0V
V
O
!
V
CC
DC Output Source/Sink Current
(I
OH
/I
OL
)
DC V
CC
or GND Current per
Supply Pin (I
CC
or GND)
Storage Temperature Range (T
STG
)
0.5V to
4.6V
0.5V to
4.6V
0.5V to
4.6V
0.5V to V
CC
0.5V
50 mA
50 mA
50 mA
r
50 mA
r
100 mA
65
q
C to
150
q
C
Recommended Operating
Conditions
(Note 4)
Power Supply
Operating
Input Voltage
Output Voltage (V
O
)
Output in Active States
Output in “OFF” State
Output Current in I
OH
/I
OL
V
CC
V
CC
V
CC
V
CC
3.0V to 3.6V
2.3V to 2.7V
1.65V to 2.3V
1.4V to 1.6V
0V to V
CC
0.0V to 3.6V
1.4V to 3.6V
0.3V to
3.6V
Free Air Operating Temperature (T
A
)
Minimum Input Edge Rate (
'
t/
'
V)
V
IN
0.8V to 2.0V, V
CC
3.0V
r
12 mA
r
8 mA
r
3 mA
r
1 mA
40
q
C to
85
q
C
10 ns/V
Note 2:
The Absolute Maximum Ratings are those values beyond which
the safety of the device cannot be guaranteed. The device should not be
operated at these limits. The parametric values defined in the Electrical
Characteristics tables are not guaranteed at the Absolute Maximum Rat-
ings. The “Recommended Operating Conditions” table will define the condi-
tions for actual device operation.
Note 3:
I
O
Absolute Maximum Rating must be observed.
Note 4:
Floating or unused inputs must be held HIGH or LOW.
DC Electrical Characteristics
Symbol
V
IH
Parameter
HIGH Level Input Voltage
Conditions
V
CC
(V)
2.7 - 3.6
2.3 - 2.7
1.65 - 2.3
1.4 - 1.6
V
IL
LOW Level Input Voltage
2.7 - 3.6
2.3 - 2.7
1.65 - 2.3
1.4 - 1.6
V
OH
HIGH Level Output Voltage
I
OH
I
OH
I
OH
I
OH
I
OH
I
OH
I
OH
I
OH
I
OH
I
OH
I
OH
I
OH
Min
2.0
1.6
0.65 x V
CC
0.65 x V
CC
0.8
0.7
0.35 x V
CC
0.35 x V
CC
V
CC
- 0.2
2.2
2.4
2.2
V
CC
- 0.2
2.0
1.8
1.7
V
CC
- 0.2
1.25
V
CC
- 0.2
1.05
V
V
V
Max
Units
100
P
A
6 mA
8 mA
12 mA
100
P
A
4 mA
6 mA
8 mA
100
P
A
3 mA
100
P
A
1 mA
2.7 - 3.6
2.7
3.0
3.0
2.3 - 2.7
2.3
2.3
2.3
1.65 - 2.3
1.65
1.4 - 1.6
1.4
3
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74VCX162373
DC Electrical Characteristics
Symbol
V
OL
Parameter
LOW Level Output Voltage
I
OL
I
OL
I
OL
I
OL
I
OL
I
OL
I
OL
I
OL
I
OL
I
OL
I
OL
I
I
I
OZ
I
OFF
I
CC
Input Leakage Current
3-STATE Output Leakage
Power-OFF Leakage Current
Quiescent Supply Current
Increase in I
CC
per Input
(Continued)
V
CC
(V)
100
P
A
6 mA
8 mA
12 mA
100
P
A
6 mA
8 mA
100
P
A
3 mA
100
P
A
1 mA
V
IH
or V
IL
2.7 - 3.6
2.7
3.0
3.0
2.3 - 2.7
2.3
2.3
1.65 - 2.3
1.65
1.4 - 1.6
1.4
1.4 - 3.6
1.4 - 3.6
0
1.4 - 3.6
1.4 - 3.6
2.7 - 3.6
0.2
0.4
0.55
0.8
0.2
0.4
0.6
0.2
0.3
0.2
0.35
V
Conditions
Min
Max
Units
0
d
V
I
d
3.6V
0
d
V
O
d
3.6V, V
I
0
d
(V
I
, V
O
)
d
3.6V
V
I
V
IH
V
CC
or GND
V
CC
0.6V
V
CC
d
(V
I
, V
O
)
d
3.6V (Note 5)
r
5.0
r
10.0
10.0
20.0
P
A
P
A
P
A
P
A
P
A
P
A
r
20.0
750
'
I
CC
Note 5:
Outputs disabled or 3-STATE only.
AC Electrical Characteristics
(Note 6)
Symbol
t
PHL
t
PLH
Parameter
Propagation Delay
LE to O
n
C
L
t
PHL
t
PLH
Propagation Delay
I
n
to O
n
C
L
t
PZL
t
PZH
C
L
t
PLZ
t
PHZ
C
L
t
S
Setup Time
C
L
15 pF, R
L
30 pF, R
L
2k
:
500
:
Output Disable Time
C
L
15 pF, R
L
30 pF, R
L
2k
:
500
:
Output Enable Time
C
L
15 pF, R
L
30 pF, R
L
2k
:
500
:
C
L
15 pF, R
L
30 pF, R
L
2k
:
500
:
C
L
Conditions
30 pF, R
L
500
:
V
CC
(V)
3.3
r
0.3
2.5
r
0.2
1.8
r
0.15
1.5
r
0.1
3.3
r
0.3
2.5
r
0.2
1.8
r
0.15
1.5
r
0.1
3.3
r
0.3
2.5
r
0.2
1.8
r
0.15
1.5
r
0.1
3.3
r
0.3
2.5
r
0.2
1.8
r
0.15
1.5
r
0.1
3.3
r
0.3
2.5
r
0.2
1.8
r
0.15
C
L
t
H
Hold Time
C
L
15 pF, R
L
30 pF, R
L
2k
:
500
:
1.5
r
0.1
3.3
r
0.3
2.5
r
0.2
1.8
r
0.15
C
L
15 pF, R
L
2k
:
1.5
r
0.1
T
A
40
q
C to
85
q
C
Max
3.6
4.9
9.8
19.6
3.3
4.5
9.0
18.0
3.9
5.4
9.8
19.6
4.0
4.4
7.9
15.8
Min
0.8
1.0
1.5
1.0
0.8
1.0
1.5
1.0
0.8
1.0
1.5
1.0
0.8
1.0
1.5
1.0
1.5
1.5
2.5
3.0
1.0
1.0
1.0
2.0
Units
Figure
Number
Figures
1, 2
Figures
7, 8
Figures
1, 2
Figures
7, 8
Figures
1, 3, 4
Figures
7, 9, 10
Figures
1, 3, 4
Figures
7, 9, 10
Figures
1, 6
Figures
6, 7
Figures
1, 6
Figures
6, 7
ns
ns
ns
ns
ns
ns
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4
74VCX162373
AC Electrical Characteristics
Symbol
t
W
Parameter
Pulse Width
C
L
(Continued)
V
CC
(V)
3.3
r
0.3
2.5
r
0.2
1.8
r
0.15
T
A
Conditions
30 pF, R
L
500
:
40
q
C to
85
q
C
Max
Units
Figure
Number
Figures
1, 5
Figures
5, 7
Min
1.5
1.5
4.0
4.0
ns
C
L
t
OSHL
t
OSLH
Output to Output Skew
(Note 7)
C
L
Note 6:
For C
L
15 pF, R
L
30 pF, R
L
2k
:
500
:
1.5
r
0.1
3.3
r
0.3
2.5
r
0.2
1.8
r
0.15
C
L
0.5
0.5
0.75
1.5
ns
15 pF, R
L
2k
:
1.5
r
0.1
50
P
F, add approximately 300 ps to the AC maximum specification.
Note 7:
Skew is defined as the absolute value of the difference between the actual propagation delay for any two separate outputs of the same device. The
specification applies to any outputs switching in the same direction, either HIGH-to-LOW (t
OSHL
) or LOW-to-HIGH (t
OSLH
).
Dynamic Switching Characteristics
Symbol
V
OLP
Parameter
Quiet Output Dynamic Peak V
OL
C
L
30 pF, V
IH
Conditions
V
CC
, V
IL
0V
V
CC
(V)
1.8
2.5
3.3
V
OLV
Quiet Output Dynamic Valley V
OL
C
L
30 pF, V
IH
V
CC
, V
IL
0V
1.8
2.5
3.3
V
OHV
Quiet Output Dynamic Valley V
OH
C
L
30 pF, V
IH
V
CC
, V
IL
0V
1.8
2.5
3.3
T
A
25
q
C
Typical
0.15
0.25
0.35
V
Units
0.15
0.25
0.35
1.55
2.05
2.65
V
V
Capacitance
Symbol
C
IN
C
OUT
C
PD
Input Capacitance
Output Capacitance
Power Dissipation Capacitance
Parameter
V
CC
V
I
V
I
V
CC
Conditions
1.8V, 2.5V or 3.3V, V
I
0V or V
CC
, V
CC
0V or V
CC
, f
10 MHz,
0V or V
CC
T
A
25
q
C
Typical
6
7
20
Units
pF
pF
pF
1.8V, 2.5V or 3.3V
1.8V, 2.5V or 3.3V
5
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