Members of the Texas Instruments

SCOPE E Family of Testability Products

Members of the Texas Instruments

WidebusE Family

Compatible With the IEEE Standard

1149.1-1990 (JTAG) Test Access Port and

Boundary-Scan Architecture

SCOPE E 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-IIBE 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

description

The ’ABT18245A scan test devices with 18-bit bus

transceivers are members of the Texas

Instruments SCOPEE 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.

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 SCOPEE 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 SCOPEE 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.