SN74ABT8245DWR.B中文资料德州仪器数据手册PDF规格书

Members of the Texas Instruments

SCOPE E Family of Testability Products

Compatible With the IEEE Standard

1149.1-1990 (JTAG) Test Access Port

and Boundary-Scan Architecture

Functionally Equivalent to ’F245 and

’ABT245 in the Normal-Function Mode

SCOPE E Instruction Set:

– IEEE Standard 1149.1-1990 Required

Instructions, Optional INTEST, CLAMP,

and HIGHZ

– Parallel-Signature Analysis at Inputs

With Masking Option

– Pseudo-Random Pattern Generation

From Outputs

– Sample Inputs/Toggle Outputs

– Binary Count From Outputs

– Even-Parity Opcodes

Two Boundary-Scan Cells per I/O for

Greater Flexibility

State-of-the-Art EPIC-IIBE BiCMOS Design

Significantly Reduces Power Dissipation

Package Options Include Plastic

Small-Outline Packages (DW), Ceramic

Chip Carriers(FK), and Standard Ceramic

DIPs (JT)

description

The ’ABT8245 scan test devices with octal bus

transceivers are members of the Texas Instruments

SCOPEE 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.

In the normal mode, these devices are functionally equivalent to the ’F245 and ’ABT245 octal bus transceivers.

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 normal mode does not affect the

functional operation of the SCOPEE octal 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. The

output-enable (OE) input can be used to disable the device so that the buses are effectively isolated.