TI SN74AS856

SDAS032A − DECEMBER 1983 − REVISED MARCH 1985
•
•
•
•
•
•
Package Options Include Plastic Small
Outline Packages, Both Plastic and
Ceramic Chip Carriers, and Standard
Plastic and Ceramic 300-mil DIPs
Buffered 3-State Outputs Drive Bus Lines
Directly
Cascadable to n-Bits
Eight Selectable Transceiver/Port
Functions:
− B to A
− Register to A and/or B
− Off-Line Shifts (A and B Ports in
High-Impedance State)
− Shifted to A and/or B
Particularly Suitable for Use in Diagnostics
Analysis Circuitry
Serial Register Provides:
− Parallel Storage of Either A or B input
Data
− Serial Transmission of Data from Either
A or B Port
− Readback Mode B to A
Dependable Texas Instruments Quality and
Reliability
description
SN54AS856 . . . JT PACKAGE
SN74AS856 . . . DW OR NT PACKAGE
(TOP VIEW)
OEB
OEA
MODE
A1
A2
A3
A4
A5
A6
A7
A8
GND
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
CLK
SERIN
B1
B2
B3
B4
B5
B6
B7
B8
Q8
SN54AS856 . . . FK PACKAGE
SN74AS856 . . . FN PACKAGE
(TOP VIEW)
MODE
OEA
OEB
NC
VCC
CLK
SERIN
•
A1
A2
A3
NC
A4
A5
A6
5
4
3 2 1 28 27 26
25
6
24
7
23
8
22
9
B1
B2
B3
NC
B4
B5
B6
A7
A8
GND
NC
Q8
B8
B7
21
The ’AS856 features two 8-bit I/O ports (A1-A8
10
20
and B1-B8), an 8-bit parallel-load, serial-in,
11
19
parallel-out shift register, and control logic. With
12 13 14 15 16 17 18
these features, this device is capable of
performing eight selectable transceiver or port
functions, depending on the state of the three
control lines OEA, OEB, and MODE. These
NC − No internal connection
functions include: transferring data from port A to
port B or vice versa (i.e., the transceiver function),
serial shifting data to either or both ports, and
performing off-line shifts (with A and B ports active
as transceivers in a high-impedance state).
Synchronous parallel loading of the internal register can be accomplished from either port on the positive
transition of the clock while serially shifting data in via the SERIN input. The ’AS856 is ideally suited for
applications needing signature-analysis circuitry to enhance system verification and/or fault analysis. All serial
data is shifted right. All outputs are buffer-type outputs designed specifically to drive bus lines directly and all
are 3-state except for Q8, which is a totem-pole output.
The SN54AS856 is characterized for operation over the full military temperature range of −55°C to 125°C. The
SN74AS856 is characterized for operation from 0°C to 70°C.
Copyright  1985, Texas Instruments Incorporated
! " #$%! " &$'(#! )!%*
)$#!" # ! "&%##!" &% !+% !%" %," "!$%!"
"!)) -!.* )$#! &#%""/ )%" ! %#%""(. #($)%
!%"!/ (( &%!%"*
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
1
2
H
H
H
L
L
L
L
L
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
L
L
L
H
H
H
L
L
L
H
H
L
L
H
H
L
L
OEB
H
L
↑
↑
L
X
↑
H or L
H
↑
L
X
↑
H or L
H
↑
L
X
↑
H or L
X
H
↑
X
↑
H or L
X
X
↑
H or L
X
X
H or L
X
↑
X
H or L
X
↑
SERIN
H or L
CLOCK
Z
Z
Z
Z
Z
Z
L
H
Q1
L
H
Q1
Z
Z
Z
Z
B1
B1
Q1
Q1
A1
L
H
Qn
L
H
Qn
L
H
Qn
L
H
Qn
A1
Q1
A1
Q1
B1
Q1
Q1
Q1
Q1
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
H
H
H
B1
Z
Z
Z
Z
Z
Z
Q1
Q1
Q2
Q1
Q1
Q2
Z
Z
Z
Z
B2
B2
Q2
Q2
A2
Q1
Q1
Qn
Q1
Q1
Qn
Q1
Q1
Qn
Q1
Q1
Qn
A2
Q2
A2
Q2
B2
Q2
Q2
Q2
Q2
Z
Z
Z
Q1
Q1
Q2
Z
Z
Z
Q1
Q1
Q2
Z
Z
A2
Q2
Z
Z
Q2
Q2
B2
Z
Z
Z
Z
Z
Z
Q2
Q2
Q3
Q2
Q2
Q3
Z
Z
Z
Z
B3
B3
Q3
Q3
A3
Q2
Q2
Qn
Q2
Q2
Qn
Q2
Q2
Qn
Q2
Q2
Qn
A3
Q3
A3
Q3
B3
Q3
Q3
Q3
Q3
Z
Z
Z
Q2
Q2
Q3
Z
Z
Z
Q2
Q2
Q3
Z
Z
A3
Q3
Z
Z
Q3
Q3
B3
Z
Z
Z
Z
Z
Z
Q3
Q3
Q4
Q3
Q3
Q4
Z
Z
Z
Z
B4
B4
Q4
Q4
A4
Q3
Q3
Qn
Q3
Q3
Qn
Q3
Q3
Qn
Q3
Q3
Qn
A4
Q4
A4
Q4
B4
Q4
Q4
Q4
Q4
Z
Z
Z
Q3
Q3
Q4
Z
Z
Z
Q3
Q3
Q4
Z
Z
A4
Q4
Z
Z
Q4
Q4
B4
Z
Z
Z
Z
Z
Z
Q4
Q4
Q5
Q4
Q4
Q5
Z
Z
Z
Z
B5
B5
Q5
Q5
A5
Q4
Q4
Qn
Q4
Q4
Qn
Q4
Q4
Qn
Q4
Q4
Qn
A5
Q5
A5
Q5
B5
Q5
Q5
Q5
Q5
Z
Z
Z
Q4
Q4
Q5
Z
Z
Z
Q4
Q4
Q5
Z
Z
A5
Q5
Z
Z
Q5
Q5
B5
Z
Z
Z
Z
Z
Z
Q5
Q5
Q6
Q5
Q5
Q6
Z
Z
Z
Z
B6
B6
Q6
Q6
A6
Q5
Q5
Qn
Q5
Q5
Qn
Q5
Q5
Qn
Q5
Q5
Qn
A6
Q6
A6
Q6
B6
Q6
Q6
Q6
Q6
Z
Z
Z
Q5
Q5
Q6
Z
Z
Z
Q5
Q5
Q6
Z
Z
A6
Q6
Z
Z
Q6
Q6
B6
Z
Z
Z
Z
Z
Z
Q6
Q6
Q7
Q6
Q6
Q7
Z
Z
Z
Z
B7
B7
Q7
Q7
A7
Q6
Q6
Qn
Q6
Q6
Qn
Q6
Q6
Qn
Q6
Q6
Qn
A7
Q7
A7
Q7
B7
Q7
Q7
Q7
Q7
Z
Z
Z
Q6
Q6
Q7
Z
Z
Z
Q6
Q6
Q7
Z
Z
A7
Q7
Z
Z
Q7
Q7
B7
Z
Z
Z
Z
Z
Z
Q7
Q7
Q8
Q7
Q7
Q8
Z
Z
Z
Z
B8
B8
Q8
Q8
A8
Q7
Q7
Qn
Q7
Q7
Qn
Q7
Q7
Qn
Q7
Q7
Qn
A8
Q8
A8
Q8
B8
Q8
Q8
Q8
Q8
Z
Z
Z
Q7
Q7
Q8
Z
Z
Z
Q7
Q7
Q8
Z
Z
A8
Q8
Z
Z
Q8
Q8
B8
Shift
B
To
Shift
A
To
Shift
A and B
To
Shift
A to Q
Q to B
A to Q
A to Q
B to A
Feedback
FUNCTION
n = level of Qn(n = 1, 2 . . 8) established on most recent ↑ transition of CLK. Q1 through Q8 are the shift register outputs; only Q8 is available externally. The double inversions
that take place as the data travels from port to port are ignored in this table.
L
H
H
L
H
L
H
L
L
L
L
L
L
L
L
H
L
L
H
OEA
MODE
MODE
FUNCTION TABLE
0
SDAS032A - DECEMBER 1983 - REVISED MARCH 1985
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
0
SDAS032A − DECEMBER 1983 − REVISED MARCH 1985
logic symbol†
1
OEB
2
OEA
3
MODE
CLK
23
22
SERIN
4
A1
(PORT CONTROLLER)
EN3
EN4
M0
M1
Z2
SRG8
2
1→/C5
≥1
Z6
Z7
6
7
1,5D
0,5D
I=0
21
3
4
8,0
9,1
A2
5
Z10
Z9
≥1
10
0,5D
I=0
Z12
19
18
17
16
15
6
7
8
9
10
11
Z28
B2
Z11
11,0
12,1
A8
20
3
4
A3
A4
A5
A6
A7
B1
Z8
≥1
28
0,5D
I=0
14
3
4
Z29
Z30
29,0
30,1
13
B3
B4
B5
B6
B7
B8
Q8
Pin numbers shown are for DW, JT, and NT packages.
† This symbol is in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
3
0
SDAS032A − DECEMBER 1983 − REVISED MARCH 1985
logic diagram (positive logic)
OEB
OEA
MODE
CLK
SERIN
1
2
3
23
22
I=0
A1
4
1D
21
B1
C1
I=0
A2
5
1D
20
B2
C1
Four Identical Channels Not Shown
Inputs/Outputs Not Shown:
(6) A3
(19) B3
(7) A4
(18) B4
(8) A5
(17) B5
(9) A6
(16) B6
I=0
A7
10
1D
15
B7
C1
I=0
A8
11
1D
C1
Pin numbers shown are for DW, JT, and NT packages.
4
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
14
13
B8
Q8
0
SDAS032A − DECEMBER 1983 − REVISED MARCH 1985
absolute maximum ratings over free-air temperature range
Supply voltage, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Input voltage: All inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
I/O ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5 V
Voltage applied to a disabled 3-state output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5 V
Operating free-air temperature range: SN54AS856 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −55°C to 125°C
SN74AS856 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0°C to 70°C
Storage temperature range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65°C to 150°C
recommended operating conditions
SN54AS856
VCC
VIH
Supply voltage
VIL
Low-level input voltage
High-level input voltage
IOH
High-level output current
IOL
Low-level output current
fclock
tw
Clock frequency
SN74AS856
MIN
NOM
MAX
MIN
NOM
MAX
4.5
5
5.5
4.5
5
5.5
2
2
0.8
−12
−15
Q8
−2
−2
A1-A8, B1-B8
32
48
Q8
20
20
0
Duration of clock pulse
45
0
11
10
A1-A8, B1-B8 SERIN
5.5
5.5
OEB, OEA, MODE
5.5
5.5
A1-A8, B1-B8 SERIN
0
0
OEB, OEA, MODE
0
0
tsu
Setup time before CLK↑
th
Hold-time, data after CLK↑
TA
Operating free-air temperature
−55
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
125
0
V
V
0.8
A1-A8, B1-B8
UNIT
50
V
mA
mA
MHz
ns
ns
ns
70
°C
5
0
SDAS032A − DECEMBER 1983 − REVISED MARCH 1985
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
VIK
II = − 18 mA
IOH = − 12 mA
2
VCC = 4.5 V,
VCC = 4.5 V to 5.5 V,
IOH = − 15 mA
IOH = − 2 mA
VCC −2
except Q8
VCC = 4.5 V,
VCC = 4.5 V,
IOL = 32 mA
IOL = 48 mA
Q8
VCC = 4.5 V,
IOL = 20 mA
CLK and SERIN
VCC = 5.5 V,
VI = 7 V
A1-A8, B1-B8
VCC = 5.5 V,
VI = 5.5 V
VCC = 5.5 V,
VI = 2.7 V
B1-B8
All outputs
All outputs
VOL
OEB, OEA, MODE
II
MIN
VCC = 4.5 V,
VCC = 4.5 V,
A1-A8
VOH
SN54AS856
TYP† MAX
TEST CONDITIONS
−1.2
CLK and SERIN
A1-A8, B1-B8‡
IO§
CLK and SERIN
A1-A8, B1-B8‡
Except Q8
Q8
VCC = 5.5 V,
VCC = 5.5 V,
2
0.25
3.3
V
0.5
0.35
VI = 0.4 V
VO = 2.25 V
V
VCC −2
OEB, OEA, MODE
IIL
−1.2
UNIT
3.2
OEB, OEA, MODE
IIH
SN74AS856
TYP† MAX
MIN
0.5
0.5
0.5
0.2
0.2
0.1
0.1
0.2
0.2
40
40
20
20
70
70
−1
−1
−0.5
−0.5
−0.5
−0.5
−30
−112
−30
−112
−20
−112
−20
−112
V
mA
µA
mA
mA
ICC
VCC = 5.5 V
118
200
118
200
mA
† All typical values are at VCC = 5 V, TA = 25°C.
‡ For I/O ports, the parameters III and IIL include the output currents IOZH and IOZL, respectively.
§ The output conditions have been chosen to produce a current that closely approximates one half of the true short-circuit output current, IOS.
6
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
0
SDAS032A − DECEMBER 1983 − REVISED MARCH 1985
switching characteristics (see Note 1)
VCC = 4.5 V to 5.5 V,
CL = 50 pF,
R1 = 500 Ω,
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
R2 = 500 Ω,
TA = MIN to MAX
SN54AS856
SN74AS856
MIN
fmax
tPLH
tPHL
tPLH
tPHL
tPLH
tPHL
tPLH
tPHL
tPLH
tPHL
tPHZ
tPLZ
tPZH
MAX
45
Any B port
↑MODE
↓MODE †
CLK
CLK
MIN
MAX
50
8
2
7
2
10.5
2
9.5
Any A or B
2
8.5
2
7.5
port
5
20
5
19
Any A or B
2
8.5
2
7.5
port
2
9.5
2
8
Any A or B
3
12
3
9
port
3
12
3
11
2
9
2
7.5
2
10
2
9
2
9
2
7
2
12
2
9.5
2
8
2
Any A port
Any A or B
port
tPZL
2
11
2
† The positive transition of the MODE control will cause low-level data at the A output bus or stored in Q to be invalid for 12 ns.
NOTE 1: Load circuit and voltage waveforms are shown in Section 1.
POST OFFICE BOX 655303
MHz
2
Q8
OEA or OEB
UNIT
• DALLAS, TEXAS 75265
7
10
ns
ns
ns
ns
ns
ns
ns
7
PACKAGE OPTION ADDENDUM
www.ti.com
18-Sep-2008
PACKAGING INFORMATION
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
SN74AS856DW
OBSOLETE
SOIC
DW
24
TBD
Call TI
Call TI
SN74AS856NT
OBSOLETE
PDIP
NT
24
TBD
Call TI
Call TI
SN74AS856NT
OBSOLETE
PDIP
NT
24
TBD
Call TI
Call TI
Lead/Ball Finish
MSL Peak Temp (3)
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in
a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check
http://www.ti.com/productcontent for the latest availability information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and
package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS
compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder
temperature.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is
provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the
accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take
reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on
incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited
information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI
to Customer on an annual basis.
Addendum-Page 1
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
Applications
Amplifiers
amplifier.ti.com
Audio
www.ti.com/audio
Data Converters
dataconverter.ti.com
Automotive
www.ti.com/automotive
DLP® Products
www.dlp.com
Communications and
Telecom
www.ti.com/communications
DSP
dsp.ti.com
Computers and
Peripherals
www.ti.com/computers
Clocks and Timers
www.ti.com/clocks
Consumer Electronics
www.ti.com/consumer-apps
Interface
interface.ti.com
Energy
www.ti.com/energy
Logic
logic.ti.com
Industrial
www.ti.com/industrial
Power Mgmt
power.ti.com
Medical
www.ti.com/medical
Microcontrollers
microcontroller.ti.com
Security
www.ti.com/security
RFID
www.ti-rfid.com
Space, Avionics &
Defense
www.ti.com/space-avionics-defense
RF/IF and ZigBee® Solutions www.ti.com/lprf
Video and Imaging
www.ti.com/video
Wireless
www.ti.com/wireless-apps
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2010, Texas Instruments Incorporated