SN54LVTH16652, SN74LVTH16652
3.3-V ABT 16-BIT BUS TRANSCEIVERS AND REGISTERS
WITH 3-STATE OUTPUTS
SCBS150K JULY 1994 REVISED APRIL 1999
1
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
D
Members of the Texas Instruments
Widebus
TM
Family
D
State-of-the-Art Advanced BiCMOS
Technology (ABT) Design for 3.3-V
Operation and Low Static-Power
Dissipation
D
Support Mixed-Mode Signal Operation
(5-V Input and Output Voltages With
3.3-V V
CC
)
D
Support Unregulated Battery Operation
Down to 2.7 V
D
Typical V
OLP
(Output Ground Bounce)
< 0.8 V at V
CC
= 3.3 V, T
A
= 25
C
D
I
off
and Power-Up 3-State Support Hot
Insertion
D
Bus Hold on Data Inputs Eliminates the
Need for External Pullup/Pulldown
Resistors
D
Distributed V
CC
and GND Pin Configuration
Minimizes High-Speed Switching Noise
D
Flow-Through Architecture Optimizes PCB
Layout
D
Latch-Up Performance Exceeds 500 mA Per
JESD 17
D
ESD Protection Exceeds 2000 V Per
MIL-STD-883, Method 3015; Exceeds 200 V
Using Machine Model (C = 200 pF, R = 0)
D
Package Options Include Plastic Shrink
Small-Outline (DL) and Thin Shrink
Small-Outline (DGG) Packages and 380-mil
Fine-Pitch Ceramic Flat (WD) Package
Using 25-mil Center-to-Center Spacings
description
The 'LVTH16652 devices are 16-bit bus transceivers designed for low-voltage (3.3-V) V
CC
operation, but with
the capability to provide a TTL interface to a 5-V system environment. These devices can be used as two 8-bit
transceivers or one 16-bit transceiver.
Output-enable (OEAB and OEBA) inputs are provided to control the transceiver functions. Select-control (SAB
and SBA) inputs are provided to select whether real-time or stored data is transferred. A low input level selects
real-time data, and a high input level selects stored data. The circuitry used for select control eliminates the
typical decoding glitch that occurs in a multiplexer during the transition between stored and real-time data.
Figure 1 illustrates the four fundamental bus-management functions that can be performed with the
'LVTH16652 devices.
Copyright
1999, Texas Instruments Incorporated
UNLESS OTHERWISE NOTED this document contains PRODUCTION
DATA information current as of publication date. Products conform to
specifications per the terms of Texas Instruments standard warranty.
Production processing does not necessarily include testing of all
parameters.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
Widebus is a trademark of Texas Instruments Incorporated.
SN54LVTH16652 . . . WD PACKAGE
SN74LVTH16652 . . . DGG OR DL PACKAGE
(TOP VIEW)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
1OEAB
1CLKAB
1SAB
GND
1A1
1A2
V
CC
1A3
1A4
1A5
GND
1A6
1A7
1A8
2A1
2A2
2A3
GND
2A4
2A5
2A6
V
CC
2A7
2A8
GND
2SAB
2CLKAB
2OEAB
1OEBA
1CLKBA
1SBA
GND
1B1
1B2
V
CC
1B3
1B4
1B5
GND
1B6
1B7
1B8
2B1
2B2
2B3
GND
2B4
2B5
2B6
V
CC
2B7
2B8
GND
2SBA
2CLKBA
2OEBA
SN54LVTH16652, SN74LVTH16652
3.3-V ABT 16-BIT BUS TRANSCEIVERS AND REGISTERS
WITH 3-STATE OUTPUTS
SCBS150K JULY 1994 REVISED APRIL 1999
2
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
description (continued)
Data on the A or B bus, or both, can be stored in the internal D flip-flops by low-to-high transitions at the
appropriate clock (CLKAB or CLKBA) inputs, regardless of the levels on the select-control or output-enable
inputs. When SAB and SBA are in the real-time transfer mode, it also is possible to store data without using the
internal D-type flip-flops by simultaneously enabling OEAB and OEBA. In this configuration, each output
reinforces its input. When all other data sources to the two sets of bus lines are at high impedance, each set
of bus lines remains at its last level configuration.
When V
CC
is between 0 and 1.5 V, the devices are in the high-impedance state during power up or power down.
However, to ensure the high-impedance state above 1.5 V, OE should be tied to V
CC
through a pullup resistor
and OE should be tied to GND through a pulldown resistor; the minimum value of the resistor is determined by
the current-sinking/current-sourcing capability of the driver.
Active bus-hold circuitry is provided to hold unused or floating data inputs at a valid logic level.
These devices are fully specified for hot-insertion applications using I
off
and power-up 3-state. The I
off
circuitry
disables the outputs, preventing damaging current backflow through the devices when they are powered down.
The power-up 3-state circuitry places the outputs in the high-impedance state during power up and power down,
which prevents driver conflict.
The SN54LVTH16652 is characterized for operation over the full military temperature range of 55
C to 125
C.
The SN74LVTH16652 is characterized for operation from 40
C to 85
C.
FUNCTION TABLE
INPUTS
DATA I/O
OPERATION OR FUNCTION
OEAB
OEBA
CLKAB
CLKBA
SAB
SBA
A1A8
B1B8
OPERATION OR FUNCTION
L
H
H or L
H or L
X
X
Input
Input
Isolation
L
H
X
X
Input
Input
Store A and B data
X
H
H or L
X
X
Input
Unspecified
Store A, hold B
H
H
X
X
Input
Output
Store A in both registers
L
X
H or L
X
X
Unspecified
Input
Hold A, store B
L
L
X
X
Output
Input
Store B in both registers
L
L
X
X
X
L
Output
Input
Real-time B data to A bus
L
L
X
H or L
X
H
Output
Input
Stored B data to A bus
H
H
X
X
L
X
Input
Output
Real-time A data to B bus
H
H
H or L
X
H
X
Input
Output
Stored A data to B bus
H
L
H or L
H or L
H
H
Output
Output
Stored A data to B bus and
stored B data to A bus
The data-output functions may be enabled or disabled by a variety of level combinations at OEAB or OEBA. Data-input functions always are
enabled; i.e., data at the bus terminals is stored on every low-to-high transition of the clock inputs.
Select control = L; clocks can occur simultaneously.
Select control = H; clocks must be staggered to load both registers.
SN54LVTH16652, SN74LVTH16652
3.3-V ABT 16-BIT BUS TRANSCEIVERS AND REGISTERS
WITH 3-STATE OUTPUTS
SCBS150K JULY 1994 REVISED APRIL 1999
3
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
BUS B
BUS A
BUS B
BUS A
BUS B
BUS A
BUS B
BUS A
OEAB
X
L
L
OEAB
L
L
CLKAB
X
CLKBA
X
SAB
X
SBA
L
CLKAB
X
CLKBA
X
SAB
L
SBA
X
H
CLKAB CLKBA
X
SAB
X
SBA
X
CLKAB
CLKBA
SAB
SBA
X
H
X
X
X
X
X
H
L
H or L
H
H
OEBA
OEBA
H
H
OEAB OEBA
OEAB OEBA
H or L
REAL-TIME TRANSFER
BUS B TO BUS A
REAL-TIME TRANSFER
BUS A TO BUS B
STORAGE FROM
A, B, OR A AND B
TRANSFER STORED DATA
TO A AND/OR B
Figure 1. Bus-Management Functions
SN54LVTH16652, SN74LVTH16652
3.3-V ABT 16-BIT BUS TRANSCEIVERS AND REGISTERS
WITH 3-STATE OUTPUTS
SCBS150K JULY 1994 REVISED APRIL 1999
4
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
logic symbol
C3
EN7 [BA]
29
G12
26
2SAB
5
1A1
1A2
6
1A3
8
1A4
9
1A5
10
1A6
12
1A7
13
1A8
14
1B6
45
1B7
44
1B8
43
1B2
51
1B3
49
1B4
48
1B5
47
1B1
52
3D
27
2CLKAB
G10
31
2SBA
30
2CLKBA
EN8 [AB]
28
2OEAB
EN1 [BA]
56
G6
3
1SAB
2
1CLKAB
G4
54
1SBA
55
1CLKBA
EN2 [AB]
1
1OEAB
C5
C9
C11
15
2A1
2A2
16
2A3
17
2A4
19
2A5
20
2A6
21
2A7
23
2A8
24
2B6
36
2B7
34
2B8
33
2B2
41
2B3
40
2B4
38
2B5
37
2B1
42
9D
1OEBA
2OEBA
5D
1
1
1
2
1
6
6
4
4
1
11D
7
1
1
8
1 12
12
10
10
1
This symbol is in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.
SN54LVTH16652, SN74LVTH16652
3.3-V ABT 16-BIT BUS TRANSCEIVERS AND REGISTERS
WITH 3-STATE OUTPUTS
SCBS150K JULY 1994 REVISED APRIL 1999
5
POST OFFICE BOX 655303
DALLAS, TEXAS 75265
logic diagram (positive logic)
1A1
1B1
One of Eight Channels
1SAB
1CLKAB
1SBA
1CLKBA
1OEAB
1OEBA
To Seven Other Channels
2A1
2B1
One of Eight Channels
2SAB
2CLKAB
2SBA
2CLKBA
2OEAB
2OEBA
To Seven Other Channels
1
55
54
2
3
5
29
28
30
31
27
26
15
1D
C1
1D
C1
52
56
42
1D
C1
1D
C1
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