The data output functions may be enabled or disabled by various signals at OEAB or OEBA inputs. Data input functions are always enabled, i.e.,
data at the bus pins will be stored on every LOW-to-HIGH transition on the clock inputs. This also applies to data I/O (A and B: 8–15) and #2 control pins
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2
74LVTH16652
Logic Diagrams
Please note that these diagrams are provided only for the understanding of logic operations and should not be used to estimate propagation delays.
3
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74LVTH16652
Functional Description
In the transceiver mode, data present at the HIGH imped-
ance port may be stored in either the A or B register or
both.
The select (SAB
n
, SBA
n
) controls can multiplex stored and
real-time.
The examples below demonstrate the four fundamental
bus-management functions that can be performed with the
LVTH16652.
Data on the A or B data bus, or both can be stored in the
internal D flip-flop by LOW-to-HIGH transitions at the
appropriate Clock Inputs (CPAB
n
, CPBA
n
) regardless of
the Select or Output Enable Inputs. When SAB and SBA
are in the real time transfer mode, it is also possible to
store data without using the internal D flip-flops by simulta-
neously enabling OEAB
n
and OEBA
n
. In this configuration
each Output reinforces its Input. Thus when all other data
sources to the two sets of bus lines are in a HIGH imped-
ance state, each set of bus lines will remain at its last state.
Real-Time Transfer
Bus B to Bus A
Storage
OEAB
1
OEBA
1
CPAB
1
CPBA
1
L
L
X
X
SAB
1
X
SBA
1
L
OEAB
1
OEBA
1
CPAB
1
CPBA
1
X
L
L
H
X
H
X
SAB
1
X
X
X
SBA
1
X
X
X
X
Real-Time Transfer
Bus A to Bus B
Transfer Storage
Data to A or B
OEAB
1
OEBA
1
CPAB
1
CPBA
1
H
H
X
X
SAB
1
L
SBA
1
X
OEAB
1
OEBA
1
CPAB
1
CPBA
1
H
L
H or L
H or L
SAB
1
H
SBA
1
H
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4
74LVTH16652
Absolute Maximum Ratings
(Note 2)
Symbol
V
CC
V
I
V
O
I
IK
I
OK
I
O
I
CC
I
GND
T
STG
Parameter
Supply Voltage
DC Input Voltage
DC Output Voltage
DC Input Diode Current
DC Output Diode Current
DC Output Current
DC Supply Current per Supply Pin
DC Ground Current per Ground Pin
Storage Temperature
Value
Conditions
Units
V
V
Output in 3-STATE
Output in HIGH or LOW State (Note 3)
V
I
<
GND
V
O
<
GND
V
O
>
V
CC
Output at HIGH State
V
O
>
V
CC
Output at LOW State
V
mA
mA
mA
mA
mA
−
0.5 to
+
4.6
−
0.5 to
+
7.0
−
0.5 to
+
7.0
−
0.5 to
+
7.0
−
50
−
50
64
128
±
64
±
128
−
65 to
+
150
°
C
Recommended Operating Conditions
Symbol
V
CC
V
I
I
OH
I
OL
T
A
Supply Voltage
Input Voltage
HIGH-Level Output Current
LOW-Level Output Current
Free-Air Operating Temperature
Input Edge Rate, V
IN
=
0.8V–2.0V, V
CC
=
3.0V
Parameter
Min
2.7
0
Max
3.6
5.5
Units
V
V
mA
mA
−
32
64
−
40
0
85
10
°
C
ns/V
∆
t/
∆
V
Note 2:
Absolute Maximum continuous ratings are those values beyond which damage to the device may occur. Exposure to these conditions or conditions
beyond those indicated may adversely affect device reliability. Functional operation under absolute maximum rated conditions is not implied.
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