SN74ABT8245

The 'ABT8245 can test devices with octal bus transceivers are members of the Texas Instruments SCOPE^TM testability integrated-circuit family. This'ABT8245  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 'ABT8245 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 SCOPE^TM octal bus transceivers.

Data flow of 'ABT8245 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.