TI SN74ABT18245ADL

SN54ABT18245A, SN74ABT18245A
SCAN TEST DEVICES
WITH 18-BIT BUS TRANSCEIVERS
SCBS110H – AUGUST 1992 – REVISED FEBRUARY 1999
D
D
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D
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Members of the Texas Instruments
SCOPE  Family of Testability Products
Members of the Texas Instruments
Widebus Family
Compatible With the IEEE Standard
1149.1-1990 (JTAG) Test Access Port and
Boundary-Scan Architecture
SCOPE  Instruction Set
– IEEE Standard 1149.1-1990 Required
Instructions, CLAMP and HIGHZ
– Parallel-Signature Analysis at Inputs
– Pseudo-Random Pattern Generation
From Outputs
– Sample Inputs/Toggle Outputs
– Binary Count From Outputs
– Device Identification
– Even-Parity Opcodes
State-of-the-Art EPIC-ΙΙB BiCMOS Design
Significantly Reduces Power Dissipation
Packaged in Plastic Shrink Small-Outline
(DL) and Thin Shrink Small-Outline (DGG)
Packages and 380-mil Fine-Pitch Ceramic
Flat (WD) Packages
SN54ABT18245A . . . WD PACKAGE
SN74ABT18245A . . . DGG OR DL PACKAGE
(TOP VIEW)
1DIR
1B1
1B2
GND
1B3
1B4
VCC
1B5
1B6
1B7
GND
1B8
1B9
2B1
2B2
2B3
2B4
GND
2B5
2B6
2B7
VCC
2B8
2B9
GND
2DIR
TDO
TMS
description
The ’ABT18245A scan test devices with 18-bit bus
transceivers are members of the Texas
Instruments SCOPE testability integratedcircuit family. This family of devices supports IEEE
Standard 1149.1-1990 boundary scan to facilitate
testing of complex circuit-board assemblies. Scan
access to the test circuitry is accomplished via the
4-wire test access port (TAP) interface.
1
56
2
55
3
54
4
53
5
52
6
51
7
50
8
49
9
48
10
47
11
46
12
45
13
44
14
43
15
42
16
41
17
40
18
39
19
38
20
37
21
36
22
35
23
34
24
33
25
32
26
31
27
30
28
29
1OE
1A1
1A2
GND
1A3
1A4
VCC
1A5
1A6
1A7
GND
1A8
1A9
2A1
2A2
2A3
2A4
GND
2A5
2A6
2A7
VCC
2A8
2A9
GND
2OE
TDI
TCK
In the normal mode, these devices are 18-bit noninverting bus transceivers. They can be used either as two
9-bit transceivers or one 18-bit transceiver. The test circuitry can be activated by the TAP to take snapshot
samples of the data appearing at the device pins or to perform a self-test on the boundary-test cells. Activating
the TAP in the normal mode does not affect the functional operation of the SCOPE bus transceivers.
Data flow is controlled by the direction-control (DIR) and output-enable (OE) inputs. Data transmission is
allowed from the A bus to the B bus or from the B bus to the A bus, depending on the logic level at DIR. OE can
be used to disable the device so that the buses are effectively isolated.
In the test mode, the normal operation of the SCOPE bus transceivers is inhibited and the test circuitry is
enabled to observe and control the input/output (I/O) boundary of the device. When enabled, the test circuitry
performs boundary-scan test operations according to the protocol described in IEEE Standard 1149.1-1990.
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.
SCOPE, Widebus, and EPIC-ΙΙB are trademarks of Texas Instruments Incorporated.
Copyright  1999, Texas Instruments Incorporated
PRODUCTION DATA information is 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.
On products compliant to MIL-PRF-38535, all parameters are tested
unless otherwise noted. On all other products, production
processing does not necessarily include testing of all parameters.
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1
SN54ABT18245A, SN74ABT18245A
SCAN TEST DEVICES
WITH 18-BIT BUS TRANSCEIVERS
SCBS110H – AUGUST 1992 – REVISED FEBRUARY 1999
description (continued)
Four dedicated test pins observe and control the operation of the test circuitry: test-data input (TDI), test-data
output (TDO), test-mode select (TMS), and test clock (TCK). Additionally, the test circuitry performs other testing
functions such as parallel-signature analysis (PSA) on data inputs and pseudo-random pattern generation
(PRPG) from data outputs. All testing and scan operations are synchronized to the TAP interface.
The SN54ABT18245A is characterized for operation over the full military temperature range of –55°C to 125°C.
The SN74ABT18245A is characterized for operation from –40°C to 85°C.
FUNCTION TABLE
(normal mode, each 9-bit section)
INPUTS
OE
2
DIR
OPERATION
L
L
B data to A bus
L
H
A data to B bus
H
X
Isolation
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• DALLAS, TEXAS 75265
SN54ABT18245A, SN74ABT18245A
SCAN TEST DEVICES
WITH 18-BIT BUS TRANSCEIVERS
SCBS110H – AUGUST 1992 – REVISED FEBRUARY 1999
functional block diagram
Boundary-Scan Register
1DIR
1OE
1A1
1
56
2
55
1B1
One of Nine Channels
2DIR
2OE
2A1
26
31
14
43
2B1
One of Nine Channels
Bypass Register
Boundary-Control
Register
Identification
Register
VCC
27
TDI
30
TDO
Instruction Register
VCC
TMS
TCK
28
29
TAP
Controller
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• DALLAS, TEXAS 75265
3
SN54ABT18245A, SN74ABT18245A
SCAN TEST DEVICES
WITH 18-BIT BUS TRANSCEIVERS
SCBS110H – AUGUST 1992 – REVISED FEBRUARY 1999
Terminal Functions
TERMINAL
NAME
1A1–1A9,
2A1–2A9
Normal-function A-bus I/O ports. See function table for normal-mode logic.
1B1–1B9,
2B1–2B9
Normal-function B-bus I/O ports. See function table for normal-mode logic.
1DIR, 2DIR
GND
1OE, 2OE
4
DESCRIPTION
Normal-function direction controls. See function table for normal-mode logic.
Ground
Normal-function output enables. See function table for normal-mode logic.
TCK
Test clock. One of four terminals required by IEEE Standard 1149.1-1990. Test operations of the device are synchronous to
TCK. Data is captured on the rising edge of TCK and outputs change on the falling edge of TCK.
TDI
Test data input. One of four terminals required by IEEE Standard 1149.1-1990. TDI is the serial input for shifting data through
the instruction register or selected data register. An internal pullup forces TDI to a high level if left unconnected.
TDO
Test data output. One of four terminals required by IEEE Standard 1149.1-1990. TDO is the serial output for shifting data
through the instruction register or selected data register.
TMS
Test mode select. One of four terminals required by IEEE Standard 1149.1-1990. TMS directs the device through its TAP
controller states. An internal pullup forces TMS to a high level if left unconnected.
VCC
Supply voltage
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN54ABT18245A, SN74ABT18245A
SCAN TEST DEVICES
WITH 18-BIT BUS TRANSCEIVERS
SCBS110H – AUGUST 1992 – REVISED FEBRUARY 1999
test architecture
Serial-test information is conveyed by means of a 4-wire test bus, or TAP, that conforms to IEEE Standard
1149.1-1990. Test instructions, test data, and test control signals all are passed along this serial-test bus. The
TAP controller monitors two signals from the test bus, TCK and TMS. The TAP controller extracts the
synchronization (TCK) and state control (TMS) signals from the test bus and generates the appropriate on-chip
control signals for the test structures in the device. Figure 1 shows the TAP-controller state diagram.
The TAP controller is fully synchronous to the TCK signal. Input data is captured on the rising edge of TCK and
output data changes on the falling edge of TCK. This scheme ensures that data to be captured is valid for fully
one-half of the TCK cycle.
The functional block diagram illustrates the IEEE Standard 1149.1-1990 4-wire test bus and boundary-scan
architecture and the relationship among the test bus, the TAP controller, and the test registers. As illustrated,
the device contains an 8-bit instruction register and four test-data registers: a 44-bit boundary-scan register, a
3-bit boundary-control register, a 1-bit bypass register, and a 32-bit device-identification register.
Test-Logic-Reset
TMS = H
TMS = L
TMS = H
TMS = H
Run-Test/Idle
TMS = H
Select-DR-Scan
Select-IR-Scan
TMS = L
TMS = L
TMS = L
TMS = H
TMS = H
Capture-DR
Capture-IR
TMS = L
TMS = L
Shift-DR
Shift-IR
TMS = L
TMS = L
TMS = H
TMS = H
TMS = H
TMS = H
Exit1-DR
Exit1-IR
TMS = L
TMS = L
Pause-DR
Pause-IR
TMS = L
TMS = L
TMS = H
TMS = H
TMS = L
Exit2-DR
TMS = L
Exit2-IR
TMS = H
Update-DR
TMS = H
TMS = L
TMS = H
Update-IR
TMS = H
TMS = L
Figure 1. TAP-Controller State Diagram
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5
SN54ABT18245A, SN74ABT18245A
SCAN TEST DEVICES
WITH 18-BIT BUS TRANSCEIVERS
SCBS110H – AUGUST 1992 – REVISED FEBRUARY 1999
state diagram description
The TAP controller is a synchronous finite-state machine that provides test control signals throughout the
device. The state diagram shown in Figure 1 is in accordance with IEEE Standard 1149.1-1990. The TAP
controller proceeds through its states based on the level of TMS at the rising edge of TCK.
As shown, the TAP controller consists of 16 states. There are six stable states (indicated by a looping arrow in
the state diagram) and ten unstable states. A stable state is a state the TAP controller can retain for consecutive
TCK cycles. Any state that does not meet this criterion is an unstable state.
There are two main paths through the state diagram: one to access and control the selected data register and
one to access and control the instruction register. Only one register can be accessed at a time.
Test-Logic-Reset
The device powers up in the Test-Logic-Reset state. In the stable Test-Logic-Reset state, the test logic is reset
and is disabled so that the normal logic function of the device is performed. The instruction register is reset to
an opcode that selects the optional IDCODE instruction, if supported, or the BYPASS instruction. Certain data
registers also can be reset to their power-up values.
The state machine is constructed such that the TAP controller returns to the Test-Logic-Reset state in no more
than five TCK cycles if TMS is left high. TMS has an internal pullup resistor that forces it high if left unconnected
or if a board defect causes it to be open circuited.
For the ’ABT18245A, the instruction register is reset to the binary value 10000001, which selects the IDCODE
instruction. Bits 43–40 in the boundary-scan register are reset to logic 0, ensuring that these cells, which control
the A-port and B-port outputs are set to benign values (i.e., if test mode were invoked, the outputs would be at
the high-impedance state). Reset values of other bits in the boundary-scan register should be considered
indeterminate. The boundary-control register is reset to the binary value 010, which selects the PSA test
operation.
Run-Test/Idle
The TAP controller must pass through the Run-Test/Idle state (from Test-Logic-Reset) before executing any test
operations. The Run-Test/Idle state also can be entered following data-register or instruction-register scans.
Run-Test/Idle is a stable state in which the test logic actively can be running a test or can be idle. The test
operations selected by the boundary-control register are performed while the TAP controller is in the
Run-Test/Idle state.
Select-DR-Scan, Select-lR-Scan
No specific function is performed in the Select-DR-Scan and Select-lR-Scan states, and the TAP controller exits
either of these states on the next TCK cycle. These states allow the selection of either data-register scan or
instruction-register scan.
Capture-DR
When a data-register scan is selected, the TAP controller must pass through the Capture-DR state. In the
Capture-DR state, the selected data register can capture a data value as specified by the current instruction.
Such capture operations occur on the rising edge of TCK, upon which the TAP controller exits the Capture-DR
state.
6
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SN54ABT18245A, SN74ABT18245A
SCAN TEST DEVICES
WITH 18-BIT BUS TRANSCEIVERS
SCBS110H – AUGUST 1992 – REVISED FEBRUARY 1999
Shift-DR
Upon entry to the Shift-DR state, the data register is placed in the scan path between TDI and TDO. On the first
falling edge of TCK, TDO goes from the high-impedance state to an active state. TDO enables to the logic level
present in the least significant bit of the selected data register.
While in the stable Shift-DR state, data is serially shifted through the selected data register on each TCK cycle.
The first shift occurs on the first rising edge of TCK after entry to the Shift-DR state (i.e., no shifting occurs during
the TCK cycle in which the TAP controller changes from Capture-DR to Shift-DR or from Exit2-DR to Shift-DR).
The last shift occurs on the rising edge of TCK, upon which the TAP controller exits the Shift-DR state.
Exit1-DR, Exit2-DR
The Exit1-DR and Exit2-DR states are temporary states that end a data-register scan. It is possible to return
to the Shift-DR state from either Exit1-DR or Exit2-DR without recapturing the data register. On the first falling
edge of TCK after entry to Exit1-DR, TDO goes from the active state to the high-impedance state.
Pause-DR
No specific function is performed in the stable Pause-DR state, in which the TAP controller can remain
indefinitely. The Pause-DR state suspends and resumes data-register scan operations without loss of data.
Update-DR
If the current instruction calls for the selected data register to be updated with current data, such updates occur
on the falling edge of TCK, following entry to the Update-DR state.
Capture-IR
When an instruction-register scan is selected, the TAP controller must pass through the Capture-IR state. In
the Capture-IR state, the instruction register captures its current status value. This capture operation occurs
on the rising edge of TCK, upon which the TAP controller exits the Capture-IR state. For the ’ABT18245A, the
status value loaded in the Capture-IR state is the fixed binary value 10000001.
Shift-IR
Upon entry to the Shift-IR state, the instruction register is placed in the scan path between TDI and TDO. On
the first falling edge of TCK, TDO goes from the high-impedance state to an active state. TDO enables to the
logic level present in the least significant bit of the instruction register.
While in the stable Shift-IR state, instruction data is serially shifted through the instruction register on each TCK
cycle. The first shift occurs on the first rising edge of TCK after entry to the Shift-IR state (i.e., no shifting occurs
during the TCK cycle in which the TAP controller changes from Capture-IR to Shift-IR or from Exit2-IR to
Shift-IR). The last shift occurs on the rising edge of TCK, upon which the TAP controller exits the Shift-IR state.
Exit1-IR, Exit2-IR
The Exit1-IR and Exit2-IR states are temporary states that end an instruction-register scan. It is possible to
return to the Shift-IR state from either Exit1-IR or Exit2-IR without recapturing the instruction register. On the
first falling edge of TCK after entry to Exit1-IR, TDO goes from the active state to the high-impedance state.
Pause-IR
No specific function is performed in the stable Pause-IR state, in which the TAP controller can remain
indefinitely. The Pause-IR state suspends and resumes instruction-register scan operations without loss of
data.
Update-IR
The current instruction is updated and takes effect on the falling edge of TCK, following entry to the Update-IR
state.
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SN54ABT18245A, SN74ABT18245A
SCAN TEST DEVICES
WITH 18-BIT BUS TRANSCEIVERS
SCBS110H – AUGUST 1992 – REVISED FEBRUARY 1999
register overview
With the exception of the bypass and device-identification registers, any test register can be thought of as a
serial-shift register with a shadow latch on each bit. The bypass and device-identification registers differ in that
they contain only a shift register. During the appropriate capture state (Capture-IR for instruction register,
Capture-DR for data registers), the shift register can be parallel loaded from a source specified by the current
instruction. During the appropriate shift state (Shift-IR or Shift-DR), the contents of the shift register are shifted
out from TDO while new contents are shifted in at TDI. During the appropriate update state (Update-IR or
Update-DR), the shadow latches are updated from the shift register.
instruction register description
The instruction register (IR) is eight bits long and tells the device what instruction is to be executed. Information
contained in the instruction includes the mode of operation (either normal mode, in which the device performs
its normal logic function, or test mode, in which the normal logic function is inhibited or altered), the test operation
to be performed, which of the four data registers is to be selected for inclusion in the scan path during
data-register scans, and the source of data to be captured into the selected data register during Capture-DR.
Table 3 lists the instructions supported by the ’ABT18245A. The even-parity feature specified for SCOPE
devices is supported in this device. Bit 7 of the instruction opcode is the parity bit. Any instructions that are
defined for SCOPE devices but are not supported by this device default to BYPASS.
During Capture-IR, the IR captures the binary value 10000001. As an instruction is shifted in, this value is shifted
out via TDO and can be inspected as verification that the IR is in the scan path. During Update-IR, the value
that has been shifted into the IR is loaded into shadow latches. At this time, the current instruction is updated
and any specified mode change takes effect. At power up or in the Test-Logic-Reset state, the IR is reset to the
binary value 10000001, which selects the IDCODE instruction. The IR order of scan is shown in Figure 2.
TDI
Bit 7
Parity
(MSB)
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Figure 2. Instruction Register Order of Scan
8
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Bit 1
Bit 0
(LSB)
TDO
SN54ABT18245A, SN74ABT18245A
SCAN TEST DEVICES
WITH 18-BIT BUS TRANSCEIVERS
SCBS110H – AUGUST 1992 – REVISED FEBRUARY 1999
data register description
boundary-scan register
The boundary-scan register (BSR) is 44 bits long. It contains one boundary-scan cell (BSC) for each
normal-function input pin, one BSC for each normal-function I/O pin (one single cell for both input data and
output data), and one BSC for each of the internally decoded output-enable signals (1OEA, 2OEA, 1OEB,
2OEB). The BSR is used to store test data that is to be applied externally to the device output pins, and/or to
capture data that appears internally at the outputs of the normal on-chip logic and/or externally at the device
input pins.
The source of data to be captured into the BSR during Capture-DR is determined by the current instruction. The
contents of the BSR can change during Run-Test/Idle, as determined by the current instruction. At power up
or in Test-Logic-Reset, BSCs 43–40 are reset to logic 0, ensuring that these cells, which control A-port and
B-port outputs, are set to benign values (i.e., if test mode were invoked, the outputs would be at the
high-impedance state). Reset values of other BSCs should be considered indeterminate.
When external data is to be captured, the BSCs for signals 1OEA, 2OEA, 1OEB, and 2OEB capture logic values
determined by the following positive-logic equations: 1OEA = 1OE • 1DIR, 2OEA = 2OE • 2DIR,
1OEB = 1OE • DIR, and 2OEB = 2OE • DIR. When data is to be applied externally, these BSCs control the
drive state (active or high impedance) of their respective outputs.
The BSR order of scan is from TDI through bits 43–0 to TDO. Table 1 shows the BSR bits and their associated
device pin signals.
Table 1. Boundary-Scan Register Configuration
BSR BIT
NUMBER
DEVICE
SIGNAL
BSR BIT
NUMBER
DEVICE
SIGNAL
BSR BIT
NUMBER
DEVICE
SIGNAL
BSR BIT
NUMBER
DEVICE
SIGNAL
BSR BIT
NUMBER
DEVICE
SIGNAL
43
2OEB
35
2A9-I/O
26
1A9-I/O
17
2B9-I/O
8
1B9-I/O
42
1OEB
34
2A8-I/O
25
1A8-I/O
16
2B8-I/O
7
1B8-I/O
41
2OEA
33
2A7-I/O
24
1A7-I/O
15
2B7-I/O
6
1B7-I/O
40
1OEA
32
2A6-I/O
23
1A6-I/O
14
2B6-I/O
5
1B6-I/O
39
2DIR
31
2A5-I/O
22
1A5-I/O
13
2B5-I/O
4
1B5-I/O
38
1DIR
30
2A4-I/O
21
1A4-I/O
12
2B4-I/O
3
1B4-I/O
37
2OE
29
2A3-I/O
20
1A3-I/O
11
2B3-I/O
2
1B3-I/O
36
1OE
28
2A2-I/O
19
1A2-I/O
10
2B2-I/O
1
1B2-I/O


27
2A1-I/O
18
1A1-I/O
9
2B1-I/O
0
1B1-I/O
boundary-control register
The boundary-control register (BCR) is three bits long. The BCR is used in the context of the boundary-run test
(RUNT) instruction to implement additional test operations not included in the basic SCOPE instruction set.
Such operations include PRPG, PSA, and binary count up (COUNT). Table 4 shows the test operations that
are decoded by the BCR.
During Capture-DR, the contents of the BCR are not changed. At power up or in Test-Logic-Reset, the BCR is
reset to the binary value 010, which selects the PSA test operation. The BCR order of scan is shown in
Figure 3.
TDI
Bit 2
(MSB)
Bit 1
Bit 0
(LSB)
TDO
Figure 3. Boundary-Control Register Order of Scan
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SN54ABT18245A, SN74ABT18245A
SCAN TEST DEVICES
WITH 18-BIT BUS TRANSCEIVERS
SCBS110H – AUGUST 1992 – REVISED FEBRUARY 1999
bypass register
The bypass register is a 1-bit scan path that can be selected to shorten the length of the system scan path,
reducing the number of bits per test pattern that must be applied to complete a test operation. During
Capture-DR, the bypass register captures a logic 0. The bypass register order of scan is shown in
Figure 4.
TDI
Bit 0
TDO
Figure 4. Bypass Register Order of Scan
device-identification register
The device-identification register (IDR) is 32 bits long. It can be selected and read to identify the manufacturer,
part number, and version of this device.
During Capture-DR, the binary value 00010000000000000101000000101111 (1000502F, hex) is captured in
the IDR to identify this device as Texas Instruments SN54/74ABT18245A. The IDR order of scan is from TDI
through bits 31–0 to TDO. Table 2 shows the IDR bits and their significance.
Table 2. Device-Identification Register Configuration
IDR BIT
NUMBER
IDENTIFICATION
SIGNIFICANCE
IDR BIT
NUMBER
IDENTIFICATION
SIGNIFICANCE
IDR BIT
NUMBER
IDENTIFICATION
SIGNIFICANCE
31
VERSION3
27
PARTNUMBER15
11
30
VERSION2
26
PARTNUMBER14
10
MANUFACTURER10†
MANUFACTURER09†
29
VERSION1
25
PARTNUMBER13
9
28
VERSION0
24
PARTNUMBER12
8


23
PARTNUMBER11
7


22
PARTNUMBER10
6


21
PARTNUMBER09
5


20
PARTNUMBER08
4


19
PARTNUMBER07
3


18
PARTNUMBER06
2


17
PARTNUMBER05
1


16
PARTNUMBER04
0
MANUFACTURER00†
LOGIC1†


15
PARTNUMBER03




14
PARTNUMBER02




13
PARTNUMBER01




12
MANUFACTURER06†
MANUFACTURER05†
MANUFACTURER04†
MANUFACTURER03†
MANUFACTURER02†
MANUFACTURER01†

† Note that for TI products, bits 11–0 of the device-identification register always contain the binary value 000000101111
(02F, hex).
10
PARTNUMBER00
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
MANUFACTURER08†
MANUFACTURER07†
SN54ABT18245A, SN74ABT18245A
SCAN TEST DEVICES
WITH 18-BIT BUS TRANSCEIVERS
SCBS110H – AUGUST 1992 – REVISED FEBRUARY 1999
instruction-register opcode description
The instruction-register opcodes are shown in Table 3. The following descriptions detail the operation of each
instruction.
Table 3. Instruction-Register Opcodes
BINARY CODE†
BIT 7 → BIT 0
MSB → LSB
SCOPE OPCODE
DESCRIPTION
SELECTED DATA
REGISTER
MODE
00000000
EXTEST
Boundary scan
Boundary scan
Test
10000001
IDCODE
Identification read
Device identification
Normal
10000010
SAMPLE/PRELOAD
BYPASS‡
Sample boundary
Boundary scan
Normal
Bypass scan
Bypass
Normal
Bypass scan
Bypass
Normal
00000101
BYPASS‡
BYPASS‡
Bypass scan
Bypass
Normal
00000110
HIGHZ
Control boundary to high impedance
Bypass
Modified test
10000111
CLAMP
BYPASS‡
Control boundary to 1/0
Bypass
Test
10001000
Bypass scan
Bypass
Normal
00001001
RUNT
Boundary-run test
Bypass
Test
00001010
READBN
Boundary read
Boundary scan
Normal
10001011
READBT
Boundary read
Boundary scan
Test
00001100
CELLTST
Boundary self test
Boundary scan
Normal
10001101
TOPHIP
Boundary toggle outputs
Bypass
Test
10001110
SCANCN
Boundary-control register scan
Boundary control
Normal
00001111
SCANCT
Boundary-control register scan
Boundary control
Test
All others
BYPASS
Bypass scan
Bypass
Normal
00000011
10000100
† Bit 7 is used to maintain even parity in the 8-bit instruction.
‡ The BYPASS instruction is executed in lieu of a SCOPE instruction that is not supported in the ’ABT18245A.
boundary scan
This instruction conforms to the IEEE Standard 1149.1-1990 EXTEST instruction. The BSR is selected in the
scan path. Data appearing at the device input and I/O pins is captured in the associated BSCs. Data that has
been scanned into the input BSCs is applied to the inputs of the normal on-chip logic, while data scanned into
the I/O BSCs for pins in the output mode is applied to the device I/O pins. Data present at the device I/O pins
is passed through the I/O BSCs to the normal on-chip logic. For I/O pins, the operation of a pin as input or output
is determined by the contents of the output-enable BSCs (bits 43–40 of the BSR). When a given output enable
is active (logic 1), the associated I/O pins operate in the output mode. Otherwise, the I/O pins operate in the
input mode. The device operates in the test mode.
identification read
This instruction conforms to the IEEE Standard 1149.1-1990 IDCODE instruction. The IDR is selected in the
scan path. The device operates in the normal mode.
sample boundary
This instruction conforms to the IEEE Standard 1149.1-1990 SAMPLE/PRELOAD instruction. The BSR is
selected in the scan path. Data appearing at the device input pins and I/O pins in the input mode is captured
in the associated BSCs, while data appearing at the outputs of the normal on-chip logic is captured in the BSCs
associated with I/O pins in the output mode. The device operates in the normal mode.
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SCBS110H – AUGUST 1992 – REVISED FEBRUARY 1999
bypass scan
This instruction conforms to the IEEE Standard 1149.1-1990 BYPASS instruction. The bypass register is
selected in the scan path. A logic 0 value is captured in the bypass register during Capture-DR. The device
operates in the normal mode.
control boundary to high impedance
This instruction conforms to the IEEE Standard 1149.1a-1993 HIGHZ instruction. The bypass register is
selected in the scan path. A logic 0 value is captured in the bypass register during Capture-DR. The device
operates in a modified test mode in which all device I/O pins are placed in the high-impedance state, the device
input pins remain operational, and the normal on-chip logic function is performed.
control boundary to 1/0
This instruction conforms to the IEEE Standard 1149.1a-1993 CLAMP instruction. The bypass register is
selected in the scan path. A logic 0 value is captured in the bypass register during Capture-DR. Data in the input
BSCs is applied to the inputs of the normal on-chip logic, while data in the I/O BSCs for pins in the output mode
is applied to the device I/O pins. The device operates in the test mode.
boundary-run test
The bypass register is selected in the scan path. A logic 0 value is captured in the bypass register during
Capture-DR. The device operates in the test mode. The test operation specified in the BCR is executed during
Run-Test/Idle. The five test operations decoded by the BCR are: sample inputs/toggle outputs (TOPSIP),
PRPG, PSA, simultaneous PSA and PRPG (PSA/PRPG), and simultaneous PSA and binary count up
(PSA/COUNT).
boundary read
The BSR is selected in the scan path. The value in the BSR remains unchanged during Capture-DR. This
instruction is useful for inspecting data after a PSA operation.
boundary self test
The BSR is selected in the scan path. All BSCs capture the inverse of their current values during Capture-DR.
In this way, the contents of the shadow latches can be read out to verify the integrity of both shift-register and
shadow-latch elements of the BSR. The device operates in the normal mode.
boundary toggle outputs
The bypass register is selected in the scan path. A logic 0 value is captured in the bypass register during
Capture-DR. Data in the shift-register elements of the selected output-mode BSCs is toggled on each rising
edge of TCK in Run-Test/Idle, updated in the shadow latches, and applied to the associated device I/O pins on
each falling edge of TCK in Run-Test/Idle. Data in the input-mode BSCs remains constant. Data appearing at
the device input or I/O pins is not captured in the input-mode BSCs. The device operates in the test mode.
boundary-control-register scan
The BCR is selected in the scan path. The value in the BCR remains unchanged during Capture-DR. This
operation must be performed before a boundary-run test operation to specify which test operation is to be
executed.
12
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boundary-control-register opcode description
The BCR opcodes are decoded from BCR bits 2–0 as shown in Table 4. The selected test operation is performed
while the RUNT instruction is executed in the Run-Test/Idle state. The following descriptions detail the operation
of each BCR instruction and illustrate the associated PSA and PRPG algorithms.
Table 4. Boundary-Control Register Opcodes
BINARY CODE
BIT 2 → BIT 0
MSB → LSB
DESCRIPTION
X00
Sample inputs/toggle outputs (TOPSIP)
X01
Pseudo-random pattern generation/36-bit mode (PRPG)
X10
Parallel-signature analysis/36-bit mode (PSA)
011
Simultaneous PSA and PRPG/18-bit mode (PSA/PRPG)
111
Simultaneous PSA and binary count up/18-bit mode (PSA/COUNT)
While the control input BSCs (bits 43–36) are not included in the toggle, PSA, PRPG, or COUNT algorithms,
the output-enable BSCs (bits 43–40 of the BSR) control the drive state (active or high impedance) of the selected
device output pins. These BCR instructions are valid only when both bytes of the device are operating in one
direction of data flow (i.e., 1OEA ≠ 1OEB and 2OEA ≠ 2OEB) and in the same direction of data flow
(i.e.,1OEA = 2OEA and 1OEB = 2OEB). Otherwise, the bypass instruction is operated.
sample inputs/toggle outputs (TOPSIP)
Data appearing at the selected device input-mode I/O pins is captured in the shift-register elements of the
associated BSCs on each rising edge of TCK. Data in the shift-register elements of the selected output-mode
BSCs is toggled on each rising edge of TCK, updated in the shadow latches, and applied to the associated
device I/O pins on each falling edge of TCK.
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pseudo-random pattern generation (PRPG)
A pseudo-random pattern is generated in the shift-register elements of the selected BSCs on each rising edge
of TCK, updated in the shadow latches, and applied to the associated device output-mode I/O pins on each
falling edge of TCK. Figures 5 and 6 illustrate the 36-bit linear-feedback shift-register algorithms through which
the patterns are generated. An initial seed value should be scanned into the BSR before performing this
operation. A seed value of all zeroes does not produce additional patterns.
2A9-I/O
2A8-I/O
2A7-I/O
2A6-I/O
2A5-I/O
2A4-I/O
2A3-I/O
2A2-I/O
2A1-I/O
1A9-I/O
1A8-I/O
1A7-I/O
1A6-I/O
1A5-I/O
1A4-I/O
1A3-I/O
1A2-I/O
1A1-I/O
2B9-I/O
2B8-I/O
2B7-I/O
2B6-I/O
2B5-I/O
2B4-I/O
2B3-I/O
2B2-I/O
2B1-I/O
1B9-I/O
1B8-I/O
1B7-I/O
1B6-I/O
1B5-I/O
1B4-I/O
1B3-I/O
1B2-I/O
1B1-I/O
=
Figure 5. 36-Bit PRPG Configuration (1OEA = 2OEA = 0, 1OEB = 2OEB = 1)
14
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pseudo-random pattern generation (PRPG) (continued)
2B9-I/O
2B8-I/O
2B7-I/O
2B6-I/O
2B5-I/O
2B4-I/O
2B3-I/O
2B2-I/O
2B1-I/O
1B9-I/O
1B8-I/O
1B7-I/O
1B6-I/O
1B5-I/O
1B4-I/O
1B3-I/O
1B2-I/O
1B1-I/O
2A9-I/O
2A8-I/O
2A7-I/O
2A6-I/O
2A5-I/O
2A4-I/O
2A3-I/O
2A2-I/O
2A1-I/O
1A9-I/O
1A8-I/O
1A7-I/O
1A6-I/O
1A5-I/O
1A4-I/O
1A3-I/O
1A2-I/O
1A1-I/O
=
Figure 6. 36-Bit PRPG Configuration (1OEA = 2OEA = 1, 1OEB = 2OEB = 0)
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parallel-signature analysis (PSA)
Data appearing at the selected device input-mode I/O pins is compressed into a 36-bit parallel signature in the
shift-register elements of the selected BSCs on each rising edge of TCK. Data in the shadow latches of the
selected output-mode BSCs remains constant and is applied to the associated device I/O pins. Figures 7 and 8
illustrate the 36-bit linear-feedback shift-register algorithms through which the signature is generated. An initial
seed value should be scanned into the BSR before performing this operation.
2A9-I/O
2A8-I/O
2A7-I/O
2A6-I/O
2A5-I/O
2A4-I/O
2A3-I/O
2A2-I/O
2A1-I/O
1A9-I/O
1A8-I/O
1A7-I/O
1A6-I/O
1A5-I/O
1A4-I/O
1A3-I/O
1A2-I/O
1A1-I/O
2B9-I/O
2B8-I/O
2B7-I/O
2B6-I/O
2B5-I/O
2B4-I/O
2B3-I/O
2B2-I/O
2B1-I/O
1B9-I/O
1B8-I/O
1B7-I/O
1B6-I/O
1B5-I/O
1B4-I/O
1B3-I/O
1B2-I/O
1B1-I/O
=
=
Figure 7. 36-Bit PSA Configuration (1OEA = 2OEA = 0, 1OEB = 2OEB = 1)
16
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parallel-signature analysis (PSA) (continued)
2B9-I/O
2B8-I/O
2B7-I/O
2B6-I/O
2B5-I/O
2B4-I/O
2B3-I/O
2B2-I/O
2B1-I/O
1B9-I/O
1B8-I/O
1B7-I/O
1B6-I/O
1B5-I/O
1B4-I/O
1B3-I/O
1B2-I/O
1B1-I/O
2A9-I/O
2A8-I/O
2A7-I/O
2A6-I/O
2A5-I/O
2A4-I/O
2A3-I/O
2A2-I/O
2A1-I/O
1A9-I/O
1A8-I/O
1A7-I/O
1A6-I/O
1A5-I/O
1A4-I/O
1A3-I/O
1A2-I/O
1A1-I/O
=
=
Figure 8. 36-Bit PSA Configuration (1OEA = 2OEA = 1, 1OEB = 2OEB = 0)
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simultaneous PSA and PRPG (PSA/PRPG)
Data appearing at the selected device input-mode I/O pins is compressed into an 18-bit parallel signature in
the shift-register elements of the selected input-mode BSCs on each rising edge of TCK. At the same time, an
18-bit pseudo-random pattern is generated in the shift-register elements of the selected output-mode BSCs on
each rising edge of TCK, updated in the shadow latches, and applied to the associated device I/O pins on each
falling edge of TCK. Figures 9 and 10 illustrate the 18-bit linear-feedback shift-register algorithms through which
the signature and patterns are generated. An initial seed value should be scanned into the BSR before
performing this operation. A seed value of all zeroes does not produce additional patterns.
2A9-I/O
2A8-I/O
2A7-I/O
2A6-I/O
2A5-I/O
2A4-I/O
2A3-I/O
2A2-I/O
2A1-I/O
1A9-I/O
1A8-I/O
1A7-I/O
1A6-I/O
1A5-I/O
1A4-I/O
1A3-I/O
1A2-I/O
1A1-I/O
2B9-I/O
2B8-I/O
2B7-I/O
2B6-I/O
2B5-I/O
2B4-I/O
2B3-I/O
2B2-I/O
2B1-I/O
1B9-I/O
1B8-I/O
1B7-I/O
1B6-I/O
1B5-I/O
1B4-I/O
1B3-I/O
1B2-I/O
1B1-I/O
=
=
Figure 9. 18-Bit PSA/PRPG Configuration (1OEA = 2OEA = 0, 1OEB = 2OEB = 1)
18
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simultaneous PSA and PRPG (PSA/PRPG) (continued)
2B9-I/O
2B8-I/O
2B7-I/O
2B6-I/O
2B5-I/O
2B4-I/O
2B3-I/O
2B2-I/O
2B1-I/O
1B9-I/O
1B8-I/O
1B7-I/O
1B6-I/O
1B5-I/O
1B4-I/O
1B3-I/O
1B2-I/O
1B1-I/O
2A9-I/O
2A8-I/O
2A7-I/O
2A6-I/O
2A5-I/O
2A4-I/O
2A3-I/O
2A2-I/O
2A1-I/O
1A9-I/O
1A8-I/O
1A7-I/O
1A6-I/O
1A5-I/O
1A4-I/O
1A3-I/O
1A2-I/O
1A1-I/O
=
=
Figure 10. 18-Bit PSA/PRPG Configuration (1OEA = 2OEA = 1, 1OEB = 2OEB = 0)
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simultaneous PSA and binary count up (PSA/COUNT)
Data appearing at the selected device input-mode I/O pins is compressed into an 18-bit parallel signature in
the shift-register elements of the selected input-mode BSCs on each rising edge of TCK. At the same time, an
18-bit binary count-up pattern is generated in the shift-register elements of the selected output-mode BSCs on
each rising edge of TCK, updated in the shadow latches, and applied to the associated device I/O pins on each
falling edge of TCK. Figures 11 and 12 illustrate the 18-bit linear-feedback shift-register algorithms through
which the signature is generated. An initial seed value should be scanned into the BSR before performing this
operation.
2A9-I/O
2A8-I/O
2A7-I/O
2A6-I/O
2A5-I/O
2A4-I/O
2A3-I/O
2A2-I/O
2A1-I/O
1A9-I/O
1A8-I/O
1A7-I/O
1A6-I/O
1A5-I/O
1A4-I/O
1A3-I/O
1A2-I/O
1A1-I/O
2B8-I/O
2B7-I/O
2B6-I/O
2B5-I/O
2B4-I/O
2B3-I/O
2B2-I/O
2B1-I/O
MSB
2B9-I/O
LSB
=
=
1B9-I/O
1B8-I/O
1B7-I/O
1B6-I/O
1B5-I/O
1B4-I/O
1B3-I/O
1B2-I/O
1B1-I/O
Figure 11. 18-Bit PSA/COUNT Configuration (1OEA = 2OEA = 0, 1OEB = 2OEB = 1)
20
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simultaneous PSA and binary count up (PSA/COUNT) (continued)
2B9-I/O
2B8-I/O
2B7-I/O
2B6-I/O
2B5-I/O
2B4-I/O
2B3-I/O
2B2-I/O
2B1-I/O
1B9-I/O
1B8-I/O
1B7-I/O
1B6-I/O
1B5-I/O
1B4-I/O
1B3-I/O
1B2-I/O
1B1-I/O
2A8-I/O
2A7-I/O
2A6-I/O
2A5-I/O
2A4-I/O
2A3-I/O
2A2-I/O
2A1-I/O
MSB
2A9-I/O
LSB
=
=
1A9-I/O
1A8-I/O
1A7-I/O
1A6-I/O
1A5-I/O
1A4-I/O
1A3-I/O
1A2-I/O
1A1-I/O
Figure 12. 18-Bit PSA/COUNT Configuration (1OEA = 2OEA = 1, 1OEB = 2OEB = 0)
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timing description
All test operations of the ’ABT18245A are synchronous to TCK. Data on the TDI, TMS, and normal-function
inputs is captured on the rising edge of TCK. Data appears on the TDO and normal-function output pins on the
falling edge of TCK. The TAP controller is advanced through its states (as shown in Figure 1) by changing the
value of TMS on the falling edge of TCK and then applying a rising edge to TCK.
A simple timing example is shown in Figure 13. In this example, the TAP controller begins in the
Test-Logic-Reset state and is advanced through its states, as necessary, to perform one instruction-register
scan and one data-register scan. While in the Shift-IR and Shift-DR states, TDI is used to input serial data and
TDO is used to output serial data. The TAP controller is then returned to the Test-Logic-Reset state. Table 5
details the operation of the test circuitry during each TCK cycle.
Table 5. Explanation of Timing Example
TCK
CYCLE(S)
TAP STATE
AFTER TCK
DESCRIPTION
1
Test-Logic-Reset
TMS is changed to a logic 0 value on the falling edge of TCK to begin advancing the TAP controller toward
the desired state.
2
Run-Test/Idle
3
Select-DR-Scan
4
Select-IR-Scan
5
Capture-IR
The IR captures the 8-bit binary value 10000001 on the rising edge of TCK as the TAP controller exits the
Capture-IR state.
6
Shift-IR
TDO becomes active and TDI is made valid on the falling edge of TCK. The first bit is shifted into the TAP
on the rising edge of TCK as the TAP controller advances to the next state.
Shift-IR
One bit is shifted into the IR on each TCK rising edge. With TDI held at a logic 1 value, the 8-bit binary value
11111111 is serially scanned into the IR. At the same time, the 8-bit binary value 10000001 is serially scanned
out of the IR via TDO. In TCK cycle 13, TMS is changed to a logic 1 value to end the IR scan on the next
TCK cycle. The last bit of the instruction is shifted as the TAP controller advances from Shift-IR to Exit1-IR.
14
Exit1-IR
TDO becomes inactive (goes to the high-impedance state) on the falling edge of TCK.
15
Update-IR
16
Select-DR-Scan
17
Capture-DR
The bypass register captures a logic 0 value on the rising edge of TCK as the TAP controller exits the
Capture-DR state.
18
Shift-DR
TDO becomes active and TDI is made valid on the falling edge of TCK. The first bit is shifted into the TAP
on the rising edge of TCK as the TAP controller advances to the next state.
19–20
Shift-DR
The binary value 101 is shifted in via TDI, while the binary value 010 is shifted out via TDO.
21
Exit1-DR
TDO becomes inactive (goes to the high-impedance state) on the falling edge of TCK.
22
Update-DR
23
Select-DR-Scan
7–13
22
24
Select-IR-Scan
25
Test-Logic-Reset
The IR is updated with the new instruction (BYPASS) on the falling edge of TCK.
The selected data register is updated with the new data on the falling edge of TCK.
Test operation completed
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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
Test-Logic-Reset
Select-IR-Scan
Select-DR-Scan
Update-DR
ÎÎÎÎÎÎ
ÎÎÎÎÎÎ
ÎÎÎÎÎÎ
ÎÎÎÎÎÎ
Exit1-DR
Capture-DR
Update-IR
Select-DR-Scan
ÎÎ
ÎÎ
ÎÎÎÎÎ
ÎÎÎÎÎ
ÎÎÎÎÎ
ÎÎÎÎÎ
Exit1-IR
Shift-IR
Capture-IR
Select-IR-Scan
TAP
Controller
State
Select-DR-Scan
TDO
ÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎ
Run-Test/Idle
TDI
Test-Logic-Reset
TMS
Shift-DR
TCK
3-State (TDO) or Don’t Care (TDI)
Figure 13. Timing Example
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, VI (except I/O ports) (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 7 V
Input voltage range, VI (I/O ports) (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 5.5 V
Voltage range applied to any output in the high state or power-off state, VO . . . . . . . . . . . . . . –0.5 V to 5.5 V
Current into any output in the low state, IO: SN54ABT18245A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 mA
SN74ABT18245A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 mA
Input clamp current, IIK (VI < 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –18 mA
Output clamp current, IOK (VO < 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –50 mA
Continuous current through VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 576 mA
Continuous current through GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1152 mA
Package thermal impedance, θJA (see Note 2): DGG package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81°C/W
DL package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74°C/W
Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –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.
NOTES: 1. The input and output negative-voltage ratings can be exceeded if the input and output clamp-current ratings are observed.
2. The package thermal impedance is calculated in accordance with JESD 51.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
23
SN54ABT18245A, SN74ABT18245A
SCAN TEST DEVICES
WITH 18-BIT BUS TRANSCEIVERS
SCBS110H – AUGUST 1992 – REVISED FEBRUARY 1999
recommended operating conditions (see Note 3)
SN54ABT18245A
SN74ABT18245A
MIN
MAX
MIN
MAX
4.5
5.5
4.5
5.5
UNIT
VCC
VIH
Supply voltage
VIL
VI
Low-level input voltage
IOH
IOL
High-level output current
VCC
–24
Low-level output current
48
64
mA
∆t/∆v
Input transition rise or fall rate
10
10
ns/V
High-level input voltage
2
2
0.8
Input voltage
0
V
0.8
0
V
VCC
–32
V
V
mA
TA
Operating free-air temperature
–55
125
–40
85
°C
NOTE 3: All unused inputs of the device must be held at VCC or GND to ensure proper device operation. Refer to the TI application report,
Implications of Slow or Floating CMOS Inputs, literature number SCBA004.
24
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN54ABT18245A, SN74ABT18245A
SCAN TEST DEVICES
WITH 18-BIT BUS TRANSCEIVERS
SCBS110H – AUGUST 1992 – REVISED FEBRUARY 1999
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
VIK
VOH
TEST CONDITIONS
VCC = 4.5 V,
VCC = 4.5 V,
II = –18 mA
IOH = –3 mA
VCC = 5 V,
VCC = 4.5 V,
VCC = 4.5 V,
3
3
2
2
IOH = –32 mA
IOL = 48 mA
2*
VCC = 5.5 V,
VI = VCC
TDI, TMS
IIL
VCC = 5.5 V,
VI = GND
TDI, TMS
IOZH‡
IOZL‡
VCC = 5.5 V,
VCC = 5.5 V,
IOZPU
VCC = 0 to 2 V,
VO = 2.7 V or 0.5 V
IOZPD
VCC = 2 V to 0,
VO = 2.7 V or 0.5 V
V
V
0.55
0.55*
A or B ports
–40
0.55
V
±1
±1
±1
±100
±100
±100
10
10
10
µA
–150
µA
–150
–40
–150
–40
µA
50
50
50
µA
–50
–50
–50
µA
OE = 0.8 V
±50
±50
±50
µA
OE = 0.8 V
±50
±50
±50
µA
±100
±450
±100
µA
50
50
50
µA
–200
mA
VO = 2.7 V
VO = 0.5 V
VCC = 0,
VCC = 5.5 V,
VO = 5.5 V
VI or VO ≤ 4.5 V
VCC = 5.5 V,
VO = 2.5 V
Outputs high
A or
Outputs high
–50
–110
–200
3.5
5
–50
–200
–50
5
5
Outputs low
33
38
38
38
Outputs disabled
2.9
4.5
4.5
4.5
50
50
50
∆ICC¶
VCC = 5.5 V,,
One input at 3.4 V,,
Other inputs at VCC or GND
Ci
VI = 2.5 V or 0.5 V
VO = 2.5 V or 0.5 V
Cio
UNIT
2
0.55
IOL = 64 mA
DIR, OE, TCK
B
ports
MAX
–1.2
3
IIH
VCC = 5.5 V,
IO = 0,
VI = VCC or GND
–1.2
IOH = –3 mA
IOH = –24 mA
VCC = 5.5 V,,
VI = VCC or GND
ICC
MIN
2.5
II
IO§
–1.2
SN74ABT18245A
2.5
VCC = 4
4.5
5V
ICEX
TA = 25°C
SN54ABT18245A
TYP†
MAX
MIN
MAX
2.5
VOL
Ioff
MIN
Control inputs
A or B ports
µA
3
9.8
pF
10
12.6
pF
Co
VO = 2.5 V or 0.5 V
TDO
8
11.4
* On products compliant to MIL-PRF-38535, this parameter does not apply.
† All typical values are at VCC = 5 V.
‡ The parameters IOZH and IOZL include the input leakage current.
§ Not more than one output should be tested at a time, and the duration of the test should not exceed one second.
¶ This is the increase in supply current for each input that is at the specified TTL voltage level rather than VCC or GND.
POST OFFICE BOX 655303
mA
• DALLAS, TEXAS 75265
pF
25
SN54ABT18245A, SN74ABT18245A
SCAN TEST DEVICES
WITH 18-BIT BUS TRANSCEIVERS
SCBS110H – AUGUST 1992 – REVISED FEBRUARY 1999
timing requirements over recommended ranges of supply voltage and operating free-air
temperature (unless otherwise noted) (test mode) (see Figure 14)
SN54ABT18245A
fclock
tw
tsu
th
td
tr
MIN
MAX
0
50
SN74ABT18245A
MIN
MAX
0
50
Clock frequency
TCK
Pulse duration
TCK high or low
8.1
8.1
A, B, DIR, or OE before TCK↑
9.5
7
Setup time
Hold time
TDI before TCK↑
4.5
4.5
TMS before TCK↑
3.6
3.6
A, B, DIR, or OE after TCK↑
0.7
0
TDI after TCK↑
Delay time
UNIT
MHz
ns
ns
ns
0
0
TMS after TCK↑
0.5
0.5
Power up to TCK↑
50*
50
ns
1*
1
µs
Rise time
VCC power up
* On products compliant to MIL-PRF-38535, these parameters are not production tested.
switching characteristics over recommended ranges of supply voltage and operating free-air
temperature (unless otherwise noted) (normal mode) (see Figure 14)
FROM
(INPUT)
TO
(OUTPUT)
tPLH
tPHL
A or B
B or A
tPZH
tPZL
OE
B or A
tPHZ
tPLZ
OE
B or A
PARAMETER
VCC = 5 V,
TA = 25°C
SN54ABT18245A
SN74ABT18245A
MIN
TYP
MAX
MIN
MAX
MIN
MAX
1.5
2.8
4.1
1.5
5.1
1.5
4.8
1.5
3.1
4.6
1.5
5.8
1.5
5.4
2
4.7
5.8
2
8.1
2
7.5
2
4.5
6.2
2
8.5
2
8
2.5
5.8
6.8
2.5
9.5
2.5
8.5
2.5
4.8
6
2.5
8.5
2.5
7.5
UNIT
ns
ns
ns
switching characteristics over recommended ranges of supply voltage and operating free-air
temperature (unless otherwise noted) (test mode) (see Figure 14)
PARAMETER
fmax
tPLH
tPHL
tPLH
tPHL
tPZH
tPZL
tPZH
tPZL
tPHZ
tPLZ
tPHZ
tPLZ
26
FROM
(INPUT)
TO
(OUTPUT)
TCK↓
TCK↓
A or B
TCK↓
TDO
TCK↓
A or B
TCK↓
TDO
TCK↓
A or B
TCK↓
TDO
VCC = 5 V,
TA = 25°C
MIN
TYP
SN54ABT18245A
MAX
MIN
MAX
50
SN74ABT18245A
MIN
50
90
3
7.1
10.1
2.8
14
3
13.1
3
7
10.1
3
13.8
3
12.8
2
3.4
5
2
6.4
2
6.1
2
3.9
5.6
2
7
2
6.5
4
7.5
10.6
4
14.1
4
13.4
4
7.6
10.5
4
14.3
4
13.6
50
MHz
2
3.8
5.5
2
7
2
6.6
2.5
4
5.7
2.3
7.3
2.5
6.9
3.5
7.7
10.8
2.9
14.4
3.5
13.6
2.5
7.1
10.1
2.5
13.8
2.5
12.7
2
3.9
5.7
2
7.5
2
7.2
1.5
3.5
5.4
1.5
6.7
1.5
6.3
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
UNIT
MAX
ns
ns
ns
ns
ns
ns
SN54ABT18245A, SN74ABT18245A
SCAN TEST DEVICES
WITH 18-BIT BUS TRANSCEIVERS
SCBS110H – AUGUST 1992 – REVISED FEBRUARY 1999
PARAMETER MEASUREMENT INFORMATION
7V
S1
500 Ω
From Output
Under Test
Open
GND
CL = 50 pF
(see Note A)
500 Ω
TEST
S1
tPLH/tPHL
tPLZ/tPZL
tPHZ/tPZH
Open
7V
Open
3V
LOAD CIRCUIT
1.5 V
Timing Input
0V
tw
tsu
3V
Input
1.5 V
3V
1.5 V
1.5 V
Data Input
0V
VOLTAGE WAVEFORMS
SETUP AND HOLD TIMES
3V
1.5 V
0V
1.5 V
1.5 V
VOH
Output
1.5 V
tPLZ
3.5 V
1.5 V
tPZH
tPLH
1.5 V
VOL
Output
Waveform 2
S1 at Open
(see Note B)
VOLTAGE WAVEFORMS
PROPAGATION DELAY TIMES
INVERTING AND NONINVERTING OUTPUTS
1.5 V
0V
Output
Waveform 1
S1 at 7 V
(see Note B)
VOL
tPHL
1.5 V
tPZL
tPHL
VOH
Output
3V
Output
Control
1.5 V
tPLH
1.5 V
0V
VOLTAGE WAVEFORMS
PULSE DURATION
Input
th
VOL + 0.3 V
VOL
tPHZ
1.5 V
VOH – 0.3 V
VOH
[0V
VOLTAGE WAVEFORMS
ENABLE AND DISABLE TIMES
LOW- AND HIGH-LEVEL ENABLING
NOTES: A. CL includes probe and jig capacitance.
B. Waveform 1 is for an output with internal conditions such that the output is low except when disabled by the output control.
Waveform 2 is for an output with internal conditions such that the output is high except when disabled by the output control.
C. All input pulses are supplied by generators having the following characteristics: PRR ≤ 10 MHz, ZO = 50 Ω, tr ≤ 2.5 ns, tf ≤ 2.5 ns.
D. The outputs are measured one at a time with one transition per measurement.
Figure 14. Load Circuit and Voltage Waveforms
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
27
PACKAGE OPTION ADDENDUM
www.ti.com
9-Oct-2007
PACKAGING INFORMATION
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
1
5962-9460102QXA
ACTIVE
CFP
WD
56
ACTIVE
TSSOP
DGG
56
2000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
74ABT18245ADGGRG4
ACTIVE
TSSOP
DGG
56
2000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
SN74ABT18245ADGGR
ACTIVE
TSSOP
DGG
56
2000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
SN74ABT18245ADL
ACTIVE
SSOP
DL
56
20
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
SN74ABT18245ADLG4
ACTIVE
SSOP
DL
56
20
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
SN74ABT18245ADLR
ACTIVE
SSOP
DL
56
1000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
SN74ABT18245ADLRG4
ACTIVE
SSOP
DL
56
1000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
SNJ54ABT18245AWD
ACTIVE
CFP
WD
56
TBD
A42 SNPB
MSL Peak Temp (3)
74ABT18245ADGGRE4
1
TBD
Lead/Ball Finish
A42 SNPB
N / A for Pkg Type
N / A for Pkg Type
(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
PACKAGE MATERIALS INFORMATION
www.ti.com
11-Mar-2008
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
Diameter Width
(mm) W1 (mm)
A0 (mm)
B0 (mm)
K0 (mm)
P1
(mm)
W
Pin1
(mm) Quadrant
SN74ABT18245ADGGR
TSSOP
DGG
56
2000
330.0
24.4
8.6
15.6
1.8
12.0
24.0
Q1
SN74ABT18245ADLR
SSOP
DL
56
1000
330.0
32.4
11.35
18.67
3.1
16.0
32.0
Q1
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
11-Mar-2008
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
SN74ABT18245ADGGR
TSSOP
DGG
56
2000
346.0
346.0
41.0
SN74ABT18245ADLR
SSOP
DL
56
1000
346.0
346.0
49.0
Pack Materials-Page 2
MECHANICAL DATA
MTSS003D – JANUARY 1995 – REVISED JANUARY 1998
DGG (R-PDSO-G**)
PLASTIC SMALL-OUTLINE PACKAGE
48 PINS SHOWN
0,27
0,17
0,50
48
0,08 M
25
6,20
6,00
8,30
7,90
0,15 NOM
Gage Plane
1
0,25
24
0°– 8°
A
0,75
0,50
Seating Plane
0,15
0,05
1,20 MAX
PINS **
0,10
48
56
64
A MAX
12,60
14,10
17,10
A MIN
12,40
13,90
16,90
DIM
4040078 / F 12/97
NOTES: A.
B.
C.
D.
All linear dimensions are in millimeters.
This drawing is subject to change without notice.
Body dimensions do not include mold protrusion not to exceed 0,15.
Falls within JEDEC MO-153
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
MECHANICAL DATA
MSSO001C – JANUARY 1995 – REVISED DECEMBER 2001
DL (R-PDSO-G**)
PLASTIC SMALL-OUTLINE PACKAGE
48 PINS SHOWN
0.025 (0,635)
0.0135 (0,343)
0.008 (0,203)
48
0.005 (0,13) M
25
0.010 (0,25)
0.005 (0,13)
0.299 (7,59)
0.291 (7,39)
0.420 (10,67)
0.395 (10,03)
Gage Plane
0.010 (0,25)
1
0°–ā8°
24
0.040 (1,02)
A
0.020 (0,51)
Seating Plane
0.110 (2,79) MAX
0.004 (0,10)
0.008 (0,20) MIN
PINS **
28
48
56
A MAX
0.380
(9,65)
0.630
(16,00)
0.730
(18,54)
A MIN
0.370
(9,40)
0.620
(15,75)
0.720
(18,29)
DIM
4040048 / E 12/01
NOTES: A.
B.
C.
D.
All linear dimensions are in inches (millimeters).
This drawing is subject to change without notice.
Body dimensions do not include mold flash or protrusion not to exceed 0.006 (0,15).
Falls within JEDEC MO-118
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
MECHANICAL DATA
MCFP010B – JANUARY 1995 – REVISED NOVEMBER 1997
WD (R-GDFP-F**)
CERAMIC DUAL FLATPACK
48 LEADS SHOWN
0.120 (3,05)
0.075 (1,91)
0.009 (0,23)
0.004 (0,10)
1.130 (28,70)
0.870 (22,10)
0.370 (9,40)
0.250 (6,35)
0.390 (9,91)
0.370 (9,40)
0.370 (9,40)
0.250 (6,35)
48
1
0.025 (0,635)
A
0.014 (0,36)
0.008 (0,20)
25
24
NO. OF
LEADS**
48
56
A MAX
0.640
(16,26)
0.740
(18,80)
A MIN
0.610
(15,49)
0.710
(18,03)
4040176 / D 10/97
NOTES: A.
B.
C.
D.
E.
All linear dimensions are in inches (millimeters).
This drawing is subject to change without notice.
This package can be hermetically sealed with a ceramic lid using glass frit.
Index point is provided on cap for terminal identification only
Falls within MIL STD 1835: GDFP1-F48 and JEDEC MO -146AA
GDFP1-F56 and JEDEC MO -146AB
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
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