SCBS050B − MAY 1990 − REVISED APRIL 1994
•
•
•
•
•
SN54BCT648 . . . JT OR W PACKAGE
SN74BCT648 . . . DW OR NT PACKAGE
(TOP VIEW)
State-of-the-Art BiCMOS Design
Significantly Reduces ICCZ
Independent Registers for A and B Buses
Multiplexed Real-Time and Stored Data
Inverting Data Paths
Power-Up High-Impedance Mode
Package Options Include Plastic
Small-Outline (DW) Packages, Ceramic
Chip Carriers (FK) and Flatpacks (W), and
Standard Plastic and Ceramic 300-mil DIPS
(JT, NT)
CLKAB
SAB
DIR
A1
A2
A3
A4
A5
A6
A7
A8
GND
description
These devices consist of bus transceiver circuits
with 3-state outputs, D-type flip-flops, and control
circuitry arranged for multiplexed transmission of
data directly from the input bus or from the internal
registers. Data on the A or B bus will be clocked
into the registers on the low-to-high transition of
the appropriate clock (CLKAB or CLKBA) input.
Figure 1 illustrates the four fundamental busmanagement functions that can be performed with
the ′BCT648.
1
24
2
23
3
22
4
21
5
20
6
19
7
18
8
17
9
16
10
15
11
14
12
13
VCC
CLKBA
SBA
OE
B1
B2
B3
B4
B5
B6
B7
B8
DIR
SAB
CLKAB
NC
VCC
CLKBA
SBA
SN54BCT648 . . . FK PACKAGE
(TOP VIEW)
4 3 2
A1
A2
A3
NC
A4
A5
A6
Output-enable (OE) and direction-control (DIR)
inputs are provided to control the transceiver
functions. In the transceiver mode, data present at
the high-impedance port may be stored in either
register or in both. The select control (SAB and
SBA) can multiplex stored and real-time
(transparent mode) data. The direction control
determines which bus will receive data when OE
is active (low). In the isolation mode (OE high), A
data may be stored in one register and/or B data
may be stored in the other register.
5
1 28 27 26
25
6
24
7
23
8
22
9
21
10
20
19
11
12 13 14 15 16 17 18
OE
B1
B2
NC
B3
B4
B5
A7
A8
GND
NC
B8
B7
B6
•
NC − No internal connection
When an output function is disabled, the input function is still enabled and may be used to store and transmit
data. Only one of the two buses, A or B, may be driven at a time.
The SN54BCT648 is characterized for operation over the full military temperature range of −55°C to 125°C. The
SN74BCT648 is characterized for operation from 0°C to 70°C.
Copyright 1994, Texas Instruments Incorporated
!"#$%! & '("")% $& ! *(+,'$%! -$%).
"!-('%& '!!"# %! &*)''$%!& *)" %/) %)"#& ! )0$& &%"(#)%&
&%$-$"- 1$""$%2. "!-('%! *"!')&&3 -!)& !% )')&&$",2 ',(-)
%)&%3 ! $,, *$"$#)%)"&.
• DALLAS, TEXAS 75265
• HOUSTON, TEXAS 77251−1443
POST OFFICE BOX 655303
POST OFFICE BOX 1443
1
21
OE
L
3
DIR
L
1
23
CLKAB CLKBA
X
X
2
SAB
X
BUS B
BUS A
BUS A
BUS B
SCBS050B − MAY 1990 − REVISED APRIL 1994
22
SBA
L
21
OE
L
3
DIR
H
3
DIR
X
X
X
1
23
CLKAB CLKBA
X
↑
X
↑
↑
↑
2
SAB
X
X
X
22
SBA
X
X
X
21
OE
L
L
STORAGE FROM
A, B, OR A AND B
22
SBA
X
BUS B
3
DIR
L
H
1
CLKAB
X
H or L
23
CLKBA
H or L
X
2
SAB
X
H
TRANSFER STORED DATA
TO A OR B
Figure 1. Bus-Management Functions
Pin numbers shown are for the DW, JT, NT, and W packages.
2
2
SAB
L
BUS A
BUS A
21
OE
X
X
H
23
CLKBA
X
REAL-TIME TRANSFER
BUS A TO BUS B
BUS B
REAL-TIME TRANSFER
BUS B TO BUS A
1
CLKAB
X
•
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
POST OFFICE BOX 1443 HOUSTON, TEXAS 77251−1443
•
22
SBA
H
X
SCBS050B − MAY 1990 − REVISED APRIL 1994
FUNCTION TABLE
INPUTS
DATA I/O
OE
DIR
CLKAB
CLKBA
SAB
SBA
A1 THRU A8
B1 THRU B8
X
X
↑
X
X
X
Input
Unspecified†
Input
OPERATION OR FUNCTION
Store A, B unspecified†
Store B, A unspecified†
X
X
X
↑
X
X
Unspecified†
H
X
↑
↑
X
X
Input
Input
Store A and B data
H
X
H or L
H or L
X
X
Input
Input
Isolation, hold storage
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
L
H
X
X
L
X
Input
Output
Real-time A data to B Bus
L
H
H or L
X
H
X
Input
Output
Stored A data to B Bus
† The data output functions may be enabled or disabled by various signals at the OE and DIR inputs. Data input functions are always enabled;
i.e., data at the bus pins will be stored on every low-to-high transition of the clock inputs.
logic symbol‡
OE
DIR
CLKBA
SBA
CLKAB
SAB
A1
21
3
23
22
1
G3
3 EN1 [BA]
3 EN2 [AB]
C4
G5
2
C6
G7
4
≥1
1
6D
5
5
≥1
A4
A5
A6
A7
A8
B1
2
7
19
A2
A3
20
5 1
7
1
4D
6
18
7
17
8
16
9
15
10
14
11
13
B2
B3
B4
B5
B6
B7
B8
‡ This symbol is in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.
Pin numbers shown are for the DW, JT, NT, and W packages.
•
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
POST OFFICE BOX 1443 HOUSTON, TEXAS 77251−1443
•
3
SCBS050B − MAY 1990 − REVISED APRIL 1994
logic diagram (positive logic)
OE
DIR
CLKBA
SBA
CLKAB
SAB
21
3
23
22
1
2
1 of 8
Channels
1D
C1
A1
4
20
1D
C1
To Seven Other Channels
Pin numbers shown are for the DW, JT, NT, and W packages.
4
•
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
POST OFFICE BOX 1443 HOUSTON, TEXAS 77251−1443
•
B1
SCBS050B − MAY 1990 − REVISED APRIL 1994
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage range, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . − 0.5 V to 7 V
Input voltage range (I/O ports) (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . − 0.5 V to 5.5 V
Input voltage range (excluding I/O ports) (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . − 0.5 V to 7 V
Voltage range applied to any output in the disabled or power-off state, VO . . . . . . . . . . . . . . . − 0.5 V to 5.5 V
Voltage range applied to any output in the high state, VO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . − 0.5 V to VCC
Current into any output in the low state: SN54BCT648 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 mA
SN74BCT648 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 mA
Operating free-air temperature range: SN54BCT648 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . − 55°C to 125°C
SN74BCT648 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0°C to 70°C
Storage temperature range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . − 65°C to 150°C
† 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.
NOTE 1: The input and output voltage ratings may be exceeded if the input and output current ratings are observed.
recommended operating conditions
SN54BCT648
SN74BCT648
MIN
NOM
MAX
MIN
NOM
MAX
4.5
5
5.5
4.5
5
5.5
UNIT
VCC
VIH
Supply voltage
VIL
IIK
Low-level input voltage
0.8
0.8
V
Input clamp current
−18
−18
mA
IOH
IOL
High-level output current
−12
−15
mA
Low-level output current
48
64
mA
TA
Operating free-air temperature
70
°C
High-level input voltage
2
−55
•
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
POST OFFICE BOX 1443 HOUSTON, TEXAS 77251−1443
•
2
125
0
V
V
5
SCBS050B − MAY 1990 − REVISED APRIL 1994
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
VIK
VCC = 4.5 V,
VOH
SN54BCT648
TYP†
MAX
TEST CONDITIONS
VCC = 4.5 V
MIN
II = −18 mA
IOH = − 3 mA
−1.2
IOH = −12 mA
IOH = −15 mA
VCC = 4.5 V
IOL = 48 mA
IOL = 64 mA
VCC = 5.5 V,
VI = 5.5 V
VCC = 5.5 V,
VI = 2.7 V
Control inputs
VCC = 5.5 V,
VI = 0.5 V
A or B port
VCC = 5.5 V,
VCC = 5.5 V,
VO = 0
VI = GND
VCC = 5.5 V,
VCC = 5.5 V,
VI = 4.5 V
VI = GND
VOL
2.4
3.3
2
3.2
0.38
Control inputs
IIH‡
IIL‡
IOS§
ICCL
ICCH
ICCZ
A or B port
Control inputs
A or B port
A or B port
A or B port
−1.2
2.4
3.3
2
3.1
−100
UNIT
V
V
0.55
0.42
A or B port
II
SN74BCT648
TYP†
MAX
MIN
0.55
1
1
1
1
70
70
20
20
−0.7
−0.7
−0.7
−0.7
−225
mA
µA
A
mA
−225
mA
42
66
mA
13
8
13
mA
16
10
16
mA
42
66
8
10
−100
V
Ci
Control inputs VCC = 5 V,
VI = 2.5 V or 0.5 V
6
Cio
A or B port
VCC = 5 V,
VO = 2.5 V or 0.5 V
12
† All typical values are at VCC = 5 V, TA = 25°C.
‡ For I/O ports, the parameters IIH and IIL include the off-state output current.
§ Not more than one output should be tested at a time, and the duration of the test should not exceed one second.
6
pF
12
pF
timing requirements over recommended ranges of supply voltage and operating free-air
temperature (unless otherwise noted)
VCC = 5 V,
TA = 25°C
fclock
Clock frequency
MIN
MAX
0
67
SN54BCT648
MIN
MAX
0
67
SN74 BCT648
MIN
MAX
0
67
CLK high
7.5
4.3
7.5
CLK low
7.5
7.5
7.5
UNIT
MHz
tw
Pulse duration
tsu
th
Setup time, A or B before CLK↑
6
6
6
ns
Hold time, A or B after CLK↑
1
1
1
ns
6
•
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
POST OFFICE BOX 1443 HOUSTON, TEXAS 77251−1443
•
ns
SCBS050B − MAY 1990 − REVISED APRIL 1994
switching characteristics over recommended ranges of supply voltage and operating free-air
temperature, CL = 50 pF (unless otherwise noted) (see Note 2)
PARAMETER
FROM
(INPUT)
VCC = 5 V,
TA = 25°C
TO
(OUTPUT)
SN54BCT648
MIN
TYP
67
110
3.7
7.4
10.3
3.7
13.4
3.7
12.1
4.3
7.8
10.6
4.3
13.2
4.3
12.5
3.8
7.4
9.9
3.8
12.8
3.8
12.2
3.3
6.5
8.9
3.3
11.2
3.3
10.1
3.3
6.2
8.4
3.3
10.7
3.3
9.7
5.3
9.6
12.6
5.3
16.5
5.3
15.5
4.6
8.8
11.7
4.6
16.5
4.6
14.3
4.9
8.4
11.1
4.9
13.8
4.9
13
4.5
8.4
11
4.5
14.4
4.5
13.5
4.9
9.2
12.2
4.9
16
4.9
15
4
7.3
9.7
4
12
4
11.2
3.5
6.6
9.3
3.5
11.6
3.5
10.5
3.1
7.4
11
3.1
14.1
3.1
13.4
3.8
8.3
12.2
3.8
15.5
3.8
14.7
4.3
8.3
11.6
3.5
14.3
4.3
DIR
A or B
tPLZ
2.7
6.7
9.9
2.7
12.8
2.7
† These parameters are measured with the internal output state of the storage register opposite to that of the bus input.
NOTE 2: Load circuits and voltage waveforms are shown in Section 1.
13.9
fmax
tPLH
tPHL
tPLH
tPHL
tPLH
tPHL
tPLH
tPHL
tPZH
tPZL
tPHZ
tPLZ
tPZH
tPZL
tPHZ
CLKBA or CLKAB
A or B
A or B
B or A
SAB or SBA†
(with A or B high)
A or B
SBA or SAB†
(with A or B low)
A or B
OE
A or B
OE
A or B
DIR
A or B
•
MAX
MAX
67
POST OFFICE BOX 655303 DALLAS, TEXAS 75265
POST OFFICE BOX 1443 HOUSTON, TEXAS 77251−1443
•
MIN
SN74BCT648
MIN
UNIT
MAX
67
MHz
11.9
ns
ns
ns
ns
ns
ns
ns
ns
7
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements,
and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should
obtain the latest relevant information before placing orders and should verify that such information is current and complete. All products are
sold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment.
TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TI’s standard
warranty. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except where
mandated by government requirements, testing of all parameters of each product is not necessarily performed.
TI assumes no liability for applications assistance or customer product design. Customers are responsible for their products and
applications using TI components. To minimize the risks associated with customer products and applications, customers should provide
adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right, copyright, mask work right,
or other TI intellectual property right relating to any combination, machine, or process in which TI products or services are used. Information
published by TI regarding third-party products or services does not constitute a license from TI to use such products or services or a
warranty or endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual
property of the third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of TI information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied
by all associated warranties, conditions, limitations, and notices. Reproduction of this information with alteration is an unfair and deceptive
business practice. TI is not responsible or liable for such altered documentation. Information of third parties may be subject to additional
restrictions.
Resale of TI products or services with statements different from or beyond the parameters stated by TI for that product or service voids all
express and any implied warranties for the associated TI product or service and is an unfair and deceptive business practice. TI is not
responsible or liable for any such statements.
TI products are not authorized for use in safety-critical applications (such as life support) where a failure of the TI product would reasonably
be expected to cause severe personal injury or death, unless officers of the parties have executed an agreement specifically governing
such use. Buyers represent that they have all necessary expertise in the safety and regulatory ramifications of their applications, and
acknowledge and agree that they are solely responsible for all legal, regulatory and safety-related requirements concerning their products
and any use of TI products in such safety-critical applications, notwithstanding any applications-related information or support that may be
provided by TI. Further, Buyers must fully indemnify TI and its representatives against any damages arising out of the use of TI products in
such safety-critical applications.
TI products are neither designed nor intended for use in military/aerospace applications or environments unless the TI products are
specifically designated by TI as military-grade or "enhanced plastic." Only products designated by TI as military-grade meet military
specifications. Buyers acknowledge and agree that any such use of TI products which TI has not designated as military-grade is solely at
the Buyer's risk, and that they are solely responsible for compliance with all legal and regulatory requirements in connection with such use.
TI products are neither designed nor intended for use in automotive applications or environments unless the specific TI products are
designated by TI as compliant with ISO/TS 16949 requirements. Buyers acknowledge and agree that, if they use any non-designated
products in automotive applications, TI will not be responsible for any failure to meet such requirements.
Following are URLs where you can obtain information on other Texas Instruments products and application solutions:
Products
Amplifiers
Data Converters
DSP
Clocks and Timers
Interface
Logic
Power Mgmt
Microcontrollers
RFID
RF/IF and ZigBee® Solutions
amplifier.ti.com
dataconverter.ti.com
dsp.ti.com
www.ti.com/clocks
interface.ti.com
logic.ti.com
power.ti.com
microcontroller.ti.com
www.ti-rfid.com
www.ti.com/lprf
Applications
Audio
Automotive
Broadband
Digital Control
Medical
Military
Optical Networking
Security
Telephony
Video & Imaging
Wireless
www.ti.com/audio
www.ti.com/automotive
www.ti.com/broadband
www.ti.com/digitalcontrol
www.ti.com/medical
www.ti.com/military
www.ti.com/opticalnetwork
www.ti.com/security
www.ti.com/telephony
www.ti.com/video
www.ti.com/wireless
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2008, Texas Instruments Incorporated