SN54LVTH182652A
SN54LVTH182652A is 3.3-V ABT SCAN TEST DEVICES manufactured by Texas Instruments.
- Part of the SN54LVTH18652A comparator family.
- Part of the SN54LVTH18652A comparator family.
description
The ’LVTH18652A and ’LVTH182652A scan test devices with 18-bit bus transceivers and registers are members of the Texas Instruments (TI) SCOPE testability integrated-circuit family. This family of devices supports IEEE Std 1149.1-1990 boundary scan to facilitate testing of plex circuit board assemblies. Scan access to the test circuitry is acplished via the 4-wire test access port (TAP) interface.
Additionally, these devices are designed specifically for low-voltage (3.3-V) VCC 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 bus transceivers and registers that allow for multiplexed transmission of data directly from the input bus or from the internal registers. 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 and registers.
Data flow in each direction is controlled by clock (CLKAB and CLKBA), select (SAB and SBA), and output-enable (OEAB and OEBA) inputs. For A-to-B data flow, data on the A bus is clocked into the associated registers on the low-to-high transition of CLKAB. When SAB is low, real-time A data is selected for presentation to the B bus (transparent mode). When SAB is high, stored A data is selected for presentation to the B bus (registered mode). When OEAB is high, the B outputs are active....