SN54LVTH18245, SN54LVTH182245, SN74LVTH18245, SN74LVTH182245
3.3-V ABT SCAN TEST DEVICES
WITH 18-BIT BUS TRANSCEIVERS
SCBS161C – AUGUST 1993 – REVISED JULY 1996
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POST OFFICE BOX 655303
DALLAS, TEXAS 75265
Members of the Texas Instruments
SCOPE
Family of Testability Products
Members of the Texas Instruments
Widebus
Family
State-of-the-Art 3.3-V ABT Design Supports
Mixed-Mode Signal Operation (5-V Input
and Output Voltages With 3.3-V V
CC
)
Support Unregulated Battery Operation
Down to 2.7 V
Bus Hold on Data Inputs Eliminates the
Need for External Pullup Resistors
B-Port Outputs of
’
LVTH182245 Devices
Have Equivalent 25-
Series Resistors, So
No External Resistors Are Required
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 and Optional 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
Packaged in Plastic Shrink Small-Outline
(DL) and Thin Shrink Small-Outline (DGG)
Packages and 380-mil Fine-Pitch Ceramic
Flat (WD) Packages
description
The ’LVTH18245 and ’LVTH182245 scan test devices with 18-bit bus transceivers are members of the Texas
Instruments SCOPE
testability integrated-circuit 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.
Additionally, these devices are designed specifically for low-voltage (3.3-V) V
CC
operation, but with the
capability to provide a TTL interface to a 5-V system environment.
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.
PRODUCT PREVIEW information concerns products in the formative or
design phase of development. Characteristic data and other
specifications are design goals. Texas Instruments reserves the right to
change or discontinue these products without notice.
Copyright
1996, Texas Instruments Incorporated
SCOPE and Widebus are trademarks of Texas Instruments Incorporated.
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1DIR
1B1
1B2
GND
1B3
1B4
V
CC
1B5
1B6
1B7
GND
1B8
1B9
2B1
2B2
2B3
2B4
GND
2B5
2B6
2B7
V
CC
2B8
2B9
GND
2DIR
TDO
TMS
1OE
1A1
1A2
GND
1A3
1A4
V
CC
1A5
1A6
1A7
GND
1A8
1A9
2A1
2A2
2A3
2A4
GND
2A5
2A6
2A7
V
CC
2A8
2A9
GND
2OE
TDI
TCK
SN54LVTH18245, SN54LVTH182245 . . . WD PACKAGE
SN74LVTH18245, SN74LVTH182245 . . . DGG OR DL PACKAGE
(TOP VIEW)
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.
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